Artilce Topics from Retail Download

Download Software Instructions by MDofPC

MDofPC Download Software Instructions

We have several types of downloadable software on our site, so we have put together a set of instructions. To make good use of these instructions it is best to determine which type of download you have purchased. The three types are listed below.

1. Executable Download (.exe) This is any download that ends in .exe

This is the easiest type of download to use and install. You should have received a email with download instructions and those instructions should have contained a download link. You can click that link to begin download, you will be given two choices.

1. Open to install or Save to have a Backup

If you cannot find the download link try to locate the download address, it will look like: http://www.mdofpc.com/Downloads/

If you do find this address copy and paste this address into your browser.

2. Zipped Download (.zip) This is any download that ends in .zip

This is a little more difficult than a executable download. You should have received an email with download instructions and those instructions should have contained a download link. You can click that link to begin download, you will be given two choices; 1. open (install) or 2. save (backup). We recommend that you choose save at this step, this will allow you to save the zipped file to your desktop. We recommend saving the file on your desktop for convenience. Once you have downloaded the file you will need to locate it on your desktop and double click to open it. There are two common ways to extract the files.

1. WinZip (available for free download at our free downloads page)

If you have winzip installed it should open and allow you to extract to a folder, you should create a temporary folder an example would be C:\Downloads . Once you have extracted the files you will need to locate the folder you created and run setup.exe (unless instructions specify otherwise, such as CD image)

Once you have your zipped file downloaded, open up Win Zip and you will see this screen:

Click on the Next button and this is the next screen you will see:

The file you downloaded may appear in this list and if it does, just click on it and then click on the Next button to proceed. But, if your zip file does not appear on the list - click on the Search button to find your zip file. This will be the next window that will open up:

Choose Let me find it (not automatic) and click on Ok. And you will get this window:

You then proceed through your folders until you find the folder where you have stored your zip file and double click on your folder.

When you find your zipped file double click on it and you will now come to this screen:

Now click on the Next button and you will see a screen with a box asking if you want to add this folder to your favorite zip folders - you can choose either Yes or No. What this question is asking is if you want to add the folder where you have stored your zip file to your favorite zip folders. For this tutorial, we chose no because we did not want our file to be unzipped into a new folder. We want to unzip our file into a folder we have already created.

Now you can choose the folder where you want to store this file.

If you want to store the unzipped contents at the folder that is in the Selected folder box, then just click Unzip Now. But if you want your files stored elsewhere, click the Select different folder button. Sometimes you may have folders set up where you wish certain contents to be saved. And if that is the case, you have the ability with Winzip to place it in the folder of your choice.

Once you have determined the folder where you want to store your unzipped file contents, click Ok.

Then the following box will appear:

Now click Unzip Now and your file contents will unzip to the folder where your files are to be stored.

2. Windows Compression Manager (windows xp default)

If you do not have winzip installed you can still extact the files. You can locate the file and double click it to open and view contents. After you have opened the file go to File at the top left of the window and choose extract files. You need to specify a folder to extract the files to an example would be C:\Downloads . Once you have extracted the files you will need to locate the folder you created and run setup.exe (unless instructions specify otherwise, such as CD image)

3. CD Image (May come in a zipped file format)

If your download is a cd image, this means that the download requires the cd to play or install properly. We provide the download instructions and program to burn the cd, to complete these steps you will need a high speed internet connection (cable or dsl) and a cd burner.

The first step would be to download the file and save it to your desktop. Then extract the files contents to a folder such as C:\Downloads. Once you have extracted the files to a folder then you will need to install alcohol 120% to burn the cd. Your download instructions should have instructions for downloading alcohol 120%.

Once you have Alcohol 120% installed you will need to choose burning wizard and then locate the files that you have extracted. Then click next and insert a blank cdr and it will burn your disk for you.

Step: 1
Install Alcohol 120%, you may download it below:

Step: 2
Start Alcohol 120%. Than click on Image Burning Wizard. Marked in the red box in the screenshot below.

Step: 3
The image burning wizard will start. Click on browse to find the image on your hard disk you want to burn. After clicking on open, Alcohol 120% will open the image and display some info about the image. Click next to continue.

Step: 4
In this screen you can select your burner if you have more than one. You can also set the burning speed. Burning at a low speed is recommended. You don't need to change the other settings with the images from our site! After choosing your burner and burning speed, click on start to burn your image.

Any problems or questions please email: webmaster@mdofpc.com or call 412-250-7965 Monday-Fri 9AM-6PM EST

Download Software and Support Overview by MDofPC

Questions about How Downloading Software Works

1.Are all download software titles Full Version and registered?

Yes, all software titles can be used as either an upgrade or full version. They are already registered and activated under MDofPC, some titles can be registered to end users.

2.Is download software the same as a retail boxed version?

Yes and no, most of our software titles are the complete retail version, but a select very few have been cut down to size for downloading purposes. If you want the full version please buy the boxed version or from a retail store near you.

3.How will my download software be delivered to me?

Most of our download software is available for immediate download and serial will be provided separately if required. The software titles that we do not have for immediate download will be sent via email within a few hours, this may be due to being updated by manufacturer or third party provider.

4.Why are your prices so inexpensive?

We are able to offer low prices because we purchase large quantities in volume and pass the savings on to our customers. Also downloadable software does not require manuals,media or shipping. We do offer quantity discounts for 5+ and 10+ purchases.

5.How long until I receive my download software?

Most orders are processed within a few hours, if there is a delay you will be notified. You should of received two confirmation emails upon purchase, the first email is from our onlinestore verifying your order. The second email is from our credit card processing to verify the amount.

6.I ordered my software but have not received any emails?

If you have placed an order and have not received any emails this may be due to your email address format, characters such as; ()-_{}+=*~`" might prevent emails from being processed. If this has happend to you please email:mdofpc@gmail.com or contact us via live support. If we are not available please leave a message or email for quick response.

7.I am not sure if I qualify for the Terms & Conditions?

Our terms and conditions are recommended guidelines that are used to be in compliance with licensing agreements. If you are in doubt if you qualify for the terms and conditions please email: webmaster@mdofpc.com or call 412-250-7965

8.How do I qualify for Academic Software?

In order to qualify for an Academic Software title you must provide us documentation showing that you meet the academic download requirements. This can be a school id, faculty id, school transcript, or any other documentation that shows that you meet the academic qualifications. Please send this information along with your order number to webmaster@mdofpc.com or fax it to 412-568-0010.

9.Does your site offer support if I purchase software?

Yes, we offer unlimited product support for up to 1 year of purchase and electronic pdf books for some titles. We also offer free upgrades for some of our download software titles as they become available by manufacturer.

10.Do you offer discounts for large orders?

Most of our prices are so low we cannot offer a discount but there are a few titles that we can make an exception for. Please contact us at webmaster@mdofpc.com or call 412-250-7965 for further details.

11.I noticed you do not have the latest version of my software?

We try to keep up with our software titles, sometimes we fall behind. If you notice something is not up to date let us know and we will have it updated within a few days.

12.I started downloading my software and the estimated time to download is several hours?

Our downloads are delivered using OC3 optical transmissions capable of up to 150mbs, however download times may vary because of:
1.Your connection to the internet typically cable/dsl connections is very fast, but a dialup or 56k will be incredibly slower.
2.If you are downloading during peak hours 10am -5pm, normally this is not a factor as the server is quite powerfull.

13.Can I get a refund for my software I purchased?

Because the software is downloadable the only way we can give you a refund is if you have proof of purchase for the same product from another retail, reseller or distributor.

14. Who provides the download software?

Download Software is not hosted at manufacturer or third parties. MDofPC only provides technical support for the software.

Burning Instructions by MDofPC

MDofPC Burning CD Images Instructions

Step: 1
Install Alcohol 120%, you may download it below:

Step: 2
Start Alcohol 120%. Than click on Image Burning Wizard. Marked in the red box in the screenshot below.

Step: 3
The image burning wizard will start. Click on browse to find the image on your harddisk you want to burn. After clicking on open, Alcohol 120% will open the image and display some info about the image. Click next to continue.

Any problems or questions please email: webmaster@mdofpc.com or call 412-250-7965

(we also have live support available between 9am to 6pm M-F and 9am to 1pm Sat)

Ahead Nero 8 Burning Rom Cd & Dvd Suite

NERO 8 WAS released only last week and replaces the popular Nero 7 Premium Reloaded from 2006. We have been looking at the retail box version, which Nero 8 now only comes on DVD and no longer on CD. The software Now comes in at a whopping 1.26GB of data, where as the downloadable version is only 182.5MB. The size difference did take us back a bit, as it has already some forum posters. Then again you really have to remember the DVD does contain all the known language versions to man.

There s also a slight difference in the install applications too, as seen in the images below. Both of those missing modules from the on-line version can be obtained from the main website if required. The Nero Mobile from the DVD is only a 30-day trial anyway, so no major loss there. Accompanying the DVD are also Photoshow Express and the Securdisc viewer, which are separately downloadable. If you re wondering what Securidisc is, check this out we covered it quite extensively in a review of late.

The variations between the installs do not stop there. On the hard drive, the full DVD installation (minus InCD) comes in at 755MB, the downloadable version is just 383MB and Nero 7 357MB. What leads the vast difference in the Nero 8 versions is their swarve and swish animated templates. The directory of the same name is full of movie files for adding to the normally plain DVD menu creations in Nero Vision. All in all, this takes up nearly-half of the final installation size from the DVD version of Nero 8.

Forum posts around Nero 8 accuse the software suite of now being bloat-ware, in light of all this. We believe this really is a hail-back to previous versions of the suite, where it was broken up. Beforehand, you could download separate parts of Nero suite and in different packages to suit all, but now it s just one size fits all and is no longer tailored.

Nero 8 installed a tad faster than 7, on our t-rusty P4 based PC. With almost minimal interruptions from the procedure itself, although at the end we were prompted to select or deselect what file types Nero should handle. We re glad this was offered and in a distinct way too. As it can be a pain to go through at a later stage picking and pulling out what file extensions you d like to be handled by your already favourite app, rather than Nero.

The very first noticeable difference, after installation, was the main applications boot up time. It s considerably faster than the previous versions to the point where we checked to see if were using the same machine. Yes, it s that much of an improvement. Nero 7 did arrive on the scene back in 2005, with an almost service-pack release under the guise Premium Reloaded late 2006. With that in mind, we d expect some over-hauls so we re glad to see this was the first. The loading times were a bother to us from beforehand, just as it was to others too.

The main core application Nero Burning ROM, hasn t changed at all from what we could see. As with prior iterations, all the disc writing aspects of Nero still run from and around it, albeit with a few crafty command switches for Nero Express. It does load quicker than before when we burnt a DVD, which didn t have any noticeable time differences from version 7.

What has changed a lot is Nero SmartStart. No longer is it just the bulky equivalent of a tool-bar just to launch applications and their functions in the Nero suite. All of which can all be launched anyway from the start menu. Now, it s actually a useful piece of software.

In Nero 8 the SmartStart application now contains all the useful and easy to access features of the complete software suite. Burning discs, creating discs, copying discs, ripping audio are all here to use. Although they have still missed out on mix-mode CDs, just as they have in Nero Express. If you know the suite anyway, the new SmartStart is a cross between the full-blown applications of Nero and also Express. It s more like a Nero Express Plus, which you could almost replace using its lite version within time. Nearly everything here is a just a few clicks away from start to finish, all easy to use too. Ideal for the not-so-techy and lazy people alike.

As you can see from the following screen shots, the most common functions and much better usage of them than Express are now built into SmartStart. They haven t left out the traditional features though. Nero 8 has them still included in an application launch bar.

They ve taken on the current and emerging trends that are all around us within High Definition media and brought it inside Nero 8. This is very clearly seen in their video authoring software, which has now been updated to version 5. As now HD media can be created with ease inside the Nero suite, although a fee playable plug-in is needed for certain aspects. It now boasts full Blue laser and HD support, for the first time so both formats can be addressed inside Nero leaving none out in the cold. This also includes support from inside their media player, ShowTime.

We ran a quick test on converting some hr hdtv avi s to DVD, Vision 5 shaved off some time in the media creation. We re sure the greater number of files we would have used, the greater the benefit in time we would have seen. Unfortunately we couldn t use the HD transcoding functions as we re sure it would have killed our poorly spec d P4 system.

From out of the box/internet, Nero have a fully-backed Vista application now. Although the previous version did install and the free updates took care of the awkwardness this is truly a Vista product. They ve integrated the UI with Aeroglass features and even thrown in a useful Windows sidebar Nero DiscCopy gadget. The latter does more or less what it says on the tin, all very easy to use.
There are a few other trinkets Nero have thrown in and improved upon, from on-line content sharing to backing-up of data. But the last thing they came to our attention and thought we should mention was the disc recover software.

Nero RescueAgent allows users to restore deleted files and recover data from discs where it may have been lost due to scratches, interrupted recordings or poor quality of media. We ve used BlindWrite before for this need, but it s useful here for those who are thwarted by damaged media and use Nero. A we lcome addition to the suite we believe, keep it up guys.

The majority of Nero sold are on-line, with a whopping 68% of all sales. We thought the retail boxes would have been a higher figure, but it only equates to 17% of sales. Then again, whenever we frequent our local supermarket-oriented-PC-wholesalers we re always tripping over boxes of Nero. T his does always mean they re selling well, despite their massive presence.

In the USA they offer an update DVD from the previous version, this we can t see on the European website which could put off possible upgraders.

In Short
Nero has made some useful improvements from the versions 7. If it s HD media creating you re going for next, then this is the package to look at. Although we re unsure if it s a significant enough change to move on from the last version, however the quick loading time and SmartStart could eventually sway us.

The Good
New improved SmartStart, faster in loading and running, HD support

The Bad
No longer separate packages

The Ugly
Could be seen as bloat-ware

Click Here for Great Prices on CD & Dvd Burning Software

Server Management by Server Buddies

We specialize in server management at a very reasonable cost. Maximizing the productivity of your server systems by keeping them monitored 24/7 on line without worrying of rebooting them if they are crashed or down. Our server management team will keep your server safe and up to date with the latest security patches/updates. Any security risk released will be patched instantly by our Server Security Management Advisers. Server management Support Staff is available 24/7 over a help desk and live chat to answer any question you may have, install any application, or troubleshoot future server management issues.

If you purchase the ServerBuddies Server Management plan your server will be fully managed and monitored round the clock. Once you place the order for our server management package, our highly trained group of System Administrators will monitor its performance and maintain your server 24 7 to ensure that it is always on line and running without any issues.
The server management includes installation and maintenance of a standard software package, services monitoring, server backups and customer support by Help Desk or email.
Every ServerBuddies Server Management plan includes Apache, MySQL, Mail and DNS server configuration.

Regular updates are also performed on the server in order to make sure you are always running a tight configuration free of spammers and hackers.

Our Server Management plan includes:

Initial Server Setup
24/7 Server Monitoring & Management
Server Tweaking
Software installation and configuration
Troubleshooting future issues
Regular Server Maintenance
Help desk and Live chat Assistance
Server Backup Configuration
Server Security Configuration (anti DDoS attack, firewall software based, and much more..)

If you have any questions regarding the server management package, please do not hesitate to contact our Support team.

$60/month

Mail Server Optimization by Server Buddies

We provide Mail Server Optimizations for persons who own a dedicated mail server, for mail propouses (newsletter, mailing list promotions, mail hosting, etc)
Most of times, a default mail server configuration takes more server load than it should when they are not configured correctly, due this you will end up having your mails stuck on the queue rather than sending the mails properly.
There is 0 chance your mail server will survive without having an RBL setup nor an anti spam solution. This plans fits when you feel your server is not sending/receiving properly.

Our Server Tweaking & Optimization plan includes:

Improved for Dedicated Mail Servers that sends up to 10,000 daily mails.
Send email to Inbox for popular mail companies such as Hotmail or Yahoo!
SpamAssassin Installation (Razor2 plugin enabled)
ClamAV, DrWeb Installation
RBL+DNSBL Setup
SPF Sender Policy Framework Setup
Yahoo! DomainKeys Setup
Reverse DNS setup
Squirrelmail/Horde Installation

Exiscan Installation (Requires Exim MTA) If you have any questions regarding the mail server optimization Support package, please do not hesitate to contact our Support team.

$75 One Time Fee

Full Server Security Audit by Server Buddies

Server Security & hardening consists of creating a baseline for the security on your servers in your organization. The default configurations are not designed with security as the primary focus. Rather, a default installed server is designed for communication and functionality. To protect your servers, you must establish solid and sophisticated security & hardening policies for all types of servers in your organization. With todays dilema of indentity theft and security breaches, if your server is not secured properly your company can lose a lot of money for this.

We provide a Full Server Security & Hardening Audit in order to investigate and track for possible intruders and spammers. Once we have checked your system is clean, we will proceed to issue a server hardening increasing your server security to prevent intruders from access your server by exploiting common vulnerabilities or injecting malicious code (iframes, exploits).

Our Full Server Security& Hardening Audit includes the following:

Full Security Audit
Intrusion Detection and Removal
Kernel Update to the latest stable release (this include applying security patches (grsecurity)
Control Panel Security Updates
OS security updates
Fix common Permission Issues in order to prevent unprivileged users to access important data.
Fix /tmp security problems
Logwatch configuration
Sysctl hardening
TCP/IP Hardening
SSH Hardening
SSH Port Change
RkHunter Installation
Advanced Policy Firewall Installation
BFD (Brute Force Detection) Installation
System priority installation
SIM (System Integrity Monitor) installation and configuration
PRM (Process Resource Monitor)
Scan of possibly enabled PHP dangerous functions
Mod_Security installation and configuration with an aggresive ruleset
Mod_dosevasive (Anti-DDoS attacks) installation and configuration
Unistallation of unused services such as telnet,fingerd,etc.
Log auditing for unusual activity

$70 One Time Fee

Initial Server Setup by Server Buddies

You just bought a new server and you dont know where to start? You feel you are lacking of knowledge on how to properly setup your server. This Initial Server Setup plan fits when a new server has been recently connected to the internet and the OS and the control panel has been recently installed. Its obviously that when you buy a fresh server you need to know where to start, this is your point of start plan. Our ServerBuddies Initial Server Setup plan includes the following:

Our Initial Server Setup plan includes:

OS and Control Panel Setup
Basic Server Security Audit
Domain Setup
DNS Setup
Apache Setup
Mysql Setup
PHP Setup
RkHunter Installation
Kernel update
APF (Advanced Policy Firewall Installation) Installation
SIM (System Priority) Installation
BFD (Brute Force Detection) Installation
SSH Server Hardening
TCP/IP Hardening
Mod_Security installation and configuration
Scan of possibly enabled PHP dangerous functions
Unistallation of unused services such as telnet,fingerd,etc.
System Integrity monitor Installation
Zend Optimizer Installation
RPM Audit

If you have any questions regarding the Initial Server Setup package, please do not hesitate to contact our Support team.

$60 one time fee

Hour of Server Support by Server Buddies

Need a one time job? Please, feel free to contact us for an estimated quote.
Most projects can easily be completed within an hour, however some may take a bit longer.
This Hour of Server Support plan includes any custom server solution you would like us to install or troubleshoot.

For Example, an Hour of Support can be used for:

MySQL Server Replication Setup
cPanel DNS Server Clustering
Apache Failover Solution
Server troubleshooting
Server Migration nor Site Migrations
Kernel upgrade
3th party Scripts Installation, Service installation and configuration
OpenSSL recompilation
PCI Compliance Setup
Mail Server Installation and Configuration
Video Sharing Site Requirements Configuration (ffmpeg,ffmpeg-php,mencoder,mplayer,lame3,etc)
Many more..!

Keep in mind we support the following control panels:

cPanel Server Support and Troubleshooting
Plesk Server Support and Troubleshooting
DirectAdmin Server Support and Troubleshooting
Webmin Server Support and Troubleshooting
Ensim Server Support and Troubleshooting

If you have any questions regarding the Hour of Server Support package, please do not hesitate to contact our Support team.

$35 per hour

Server Tweaking & Optimization by Server Buddies

We provide Server Tweaking & Optimization to successfully increase how your server responds to your customers.
We optimize & Tweak your server settings in order to speed up the server performance.
Optimization Tweaking Services boosts up your server performance to the maximum.
Optimize your server by improving how your kernel interacts with your hardware server, decrease the time responses between the kernel and the server hardware.

Is your server under heavy overload? Are you experiencing slow time responses? Did you just buy a expensive server and you feel like its not performing as it should?
Adding new server hardware is often not the best choice, here where ServerBuddies comes in! Our ServerBuddies Server Tweaking & Optimization plan is the right choice for this cases. There are many things to consider when optimizing a server. The most important one is to know the best performance you server hardware can give. We analyze everything in your server environment including RAM, CPU Proc, Hard Disks, Swap memory, Network, Kernel Version and Linux OS.
Our ServerBudies Server Tweaking & Optimization plan can really boost up your server performance so you will not feel bad experiences anymore.

Our Server Tweaking & Optimization plan includes:

Hand compiling of latest system kernel from source.
Remove some kernel bloat for performance.
Includes sysctl performance optimizations.
Improve disk read/write performance
Improve network thoroughput
Various other minor tweaks and configuration optimizations
Apache Web Server Optimization
MySQL Service Database Optimizations
Disabling/Removal of unused OS services
PHP OPtimization (eAccelerator Installtion)
Custom Server Optimizations

If you have any questions regarding the server tweaking & optimization package, please do not hesitate to contact our Support team.

$50 one time fee

Coraopolis PA 15108 Onsite Computer Repair Service by MDofPC

We offer onsite computer repair service for personal and businesses at a flat rate price. There are no suprise costs and you will be given an estimate over the phone or when we arrive onsite. We charge $35 to come out up to 30 miles from our location and then $35 a hour once
we arrive onsite and work begins.

Our technicians will try to advise you of the best method to fix your computer or computers as we offer a wide array of services. In some cases it might be better to have our technician pick up the machine and have it serviced at our shop, this is due to the hours it can take to repair. On occassion virus's and spyware can leave windows corrupted beyond reasonable repair, when this happens it is much cheaper to have the computer serviced in house.

Your private data and personal information is our highest importantance, keeping your data intact and your personal information secure. Our technician will ask you a few questions to make sure everything is the way you want it, giving you a wide variety of options. If your computer needs to be reloaded your data will be saved on a secure drive and restored afterwards. Also your personal information stays personal such as passwords, business documents, pictures and other related documents.

Onsite Computer Repair Services include but are not limited to:

Virus Detection & Removal, Spyware Detection & Removal, Windows Updates & Service Packs, Unlimited Antivirus Protection, Unlimited Spyware Protection, Registry Repair & Optimization, Remove Unnecessary Programs, Free Up Additional Ram, Remove Internet History & Temporary Files, Defragment Hard Drive, Provide Automatic Hard Drive Defrag, Troubleshoot & Install Printer Issues, Troubleshoot & Install Scanner Issues, Speed Up Internet Access, Upgrade Memory, Fix Broken Power Jacks, Replace Bad Power Supplies or Adapters, Dust & Debri Removal From PC, Upgrade & Replace Hard Drive, Troubleshoot & Replace Motherboard, Upgrade & Replace CD & DVd & BluRay Drives, Troubleshoot Network Issues, Upgrade or New Network Installations, Wireless Networking, Replace Cooling Fans, Replace & Fix Broken LCD Screens, Complete Laptop & Notebook Repairs, Data Restoration, Setup & Configure Backup and much more!

All service work carries a 30 day warranty from the date it was performed. All technicians are Microsoft and CompTia Certified with at least 5 years of experience.

Onsite Fee is $35 up to 30 miles away
Hourly service rate is $35 per hour

Call 412-680-1134 or email: mdofpc@gmail.com for more information

Mesh Computers (buyer Beware)

Mesh computers account was recently placed on stop by Repair-Line Ltd , all services to the manufacturer are being withheld due to non payment of account and failure to exchange parts buffer stock to allow repairs to continue.

Repair-Line Ltd signed an agreement with Mesh computers to commence the 1 st of May 2007 the agreement was that Repair-Line Ltd would provide on site support to Mesh clients and all PCs sold from the 1 st of May 2007 would be provided with on site warranty, Mesh drove the charges down with false promises of sales volume of PCs which would carry 1 and 3 year warranties, Mesh paid only 5 per 1 year warranty, 49 per 2 Year Warranty and 59 per 3 year warranty. At the time of signing the agreement Max Sherafati the owner and MD of Mesh Computers Ltd formally Mesh Computers PLC stated his sales were in excess of 50,000 units per year and 20% of those would be covered with 3 year warranty. The actual figure turned out to be around 20,000 and 5% with 3 year warranty. Mesh has made a large number of people redundant in the last year and their sales have plummeted to probably what is an all time low. They were featured for their terrible customer service on watchdog prior to arranging service to be provided by Repair-Line Ltd. Despite the claims they made in a statement to watchdog that they have increased customer service staff which they have not they still have no concept for providing good customer care, the only customer care seen is when a client wants a refund or they start to take court action. The mesh offices are a now a big open space with a little gathering of people to one side, the staff and even desks have gone which is strange for company increasing its staff levels.

Max Sherafati took on Paul Kinsler and introduced him as the new MD, Paul however likes to be know as the acting MD or General Manager as it seems he is still operating his own Business called PK Media information on which can be found at http://www.pkmedia.co.uk . Paul likes to disassociate himself with Mesh just in case the inevitable happens and they fall. Paul, everyone is lead to believe does not want his relationship with the Media to be effected by his association with Max Sherafati and Mesh Computers. Paul subsequently took charge and Max was no longer contactable the last claims are he is in Iran living his life in his Mansion complete with servants to tend his ever need. Paul decided to make changes and stopped any systems being sold with 3 year onsite warranty, this was his first move next he introduced the idea he only wanted to pay if a client registered the warranty, under Paul s control the only 3 year warranty provision was if the customer was sold it as an upgrade and Mesh made money from it and the only warranty he paid for was if it was registered though a web page, however he still expected every machine to be covered. Later it came to light that approximately 2000 warranties had not been declared by Mesh to Repair-Line ltd yet they had been expecting support to be provided, this was claimed to be a genuine mistake with the daily exports of sales data however the first time this may have been a good excuse but the situation continued and then it became obvious the reasons for the non disclosure, with no data declared Repair-Line Ltd could not invoice for the cover! Mesh it seemed was clearly in trouble.

In February 2008 Paul Kinsler representing Mesh at this time as Acting MD Management Consultant informed Repair-Line Ltd that Mesh could no longer afford to provide free on site warranty for even 1 year to its clients at the cost of 5 per unit and he went on to say the decision was purely financial with no mention of any lack of service or support from the company he wanted to still offer service but the end user had to pay for it, he was informed to do this he was in breach of contract as the agreement was all systems sold would carry on site support and his subsequent action was to tender 3 months of termination. Should any one to see the actual email simply email mesh@repairline.co.uk and the mail will be sent to you.

Although Sales were very low over the period the failure rate certainly was not and with over 30% of units failing the cost of stock to maintain the poorly built systems was huge! Mesh should have arranged with all its suppliers to allow exchanges to be done direct but they failed to do so and thus eventually had to agree to carry out the exchanges from the buffer stock Repair-Line Ltd had which it had bought and paid for to the value of 150K just for initial stock , Whilst it seemed we were starting to make progress and could stop spending on Stock to maintain the systems as the parts already replaced and left faulty would be replaced at long last the exchanges were replaced by Mesh with faulty second hand goods and thus the majority of systems which needed repair needed far more than one visit to achieve a stable working system with these parts. Clients could have a 1 week old computer and Mesh expected them to be repaired with old second hand faulty parts. This coupled with the poor payment history meant Repair-Line Ltd placed the Mesh account on stop for what would be the 5th time in less than 12 months. All work ceased for Mesh and they are now left looking for another service provider to use who will no doubt gain little reward for their efforts. Any service provider who takes on this company should be well experienced at debt collection and the best advice would be to seek at least 100K on account and don t provide your own buffer stock it will work out very expensive and be a magical experience, new stock will disappear before their very eyes and be replaced with non usable old parts. Paul Daniels himself could not perform a better trick.

Mesh it seems have a terrible reputation for payment throughout the trade so it is not only service providers they dislike paying and as a result they have set up another company formed by Max along Ray the purchase manager for Mesh and Max s brother in law Mohsen, with this new partnership MRM International Ltd was formed in May 2007 with a registered office in Kent. This is now the purchasing arm used by Mesh.

Whilst it is easy for everyone to blame the service provider for lack of service its is well worth remembering any service provider is only as good as the company it works with, if they are not paid, provided with faulty parts to repair systems and the manufacturer has no concept for support and customer care and is only concerned with making sales and taking your money then it is a difficult battle for any service provider to provide first class service to the end user.

Turn Your Laptop Into a Touch Screen Laptop

The purpose of touch screen technology is to give its users an interface that is both effective and intuitive. There are two tools in the world that we rely on most for the manipulation of our environment, the expression of our creative minds, and any matter in between. This is why everyone got so excited with the emergence of multi-touch technology. But when it comes to touch screen laptops, this feature is only available with very select high-end models. That is, until N-Trig released the DuoSense , the only digitizer in the market that recognizes the pen, touch, and multi-touch.

The product fits over any laptop screen to convert your regular non-touch screen laptop into a fully functioning pen, touch, and multi-touch enabled screen. The product is very well designed noninvasive thin screen that fits over the laptop nicely. It can be held into place with air gap bonding, PSA, or direct bonding and uses a gel to minimize reflecting glare. That allows the user to function perfectly unaffected by the brightness when outdoors.

The pen itself is quite the work of wonder. It has an electric-magnetic charge in itself that interacts with the screen without the need for an external power source. The pressure sensitive tip recognizes the difference in the strokes and taps of the user. During artistic functions, heavy and light strokes are digitized on screen in a manner that intuitively mimics a pen or brush stroke. It even has eraser capabilities when used in drawing or writing programs. Outside of drawing programs the stylus serves well in navigating. The DuoSense allows the use of the pen in much the same way as a computer mouse with right click capabilities.

The touch technology uses fractional pixel recognition for the most pinpoint accuracy in touch response. The capacitive design of the touch screen eliminates the use of traditional touch screen spacer dots that compromises the accuracy of the pen. It offers the fastest response time in the history of touch screen technology and there are no accidental drops with the click and drag function and the touch pad comes with what the company terms the palm rejection feature. It recognizes the difference between intentional and accidental touches.

The DuoSense is light and thin for easy integration over a regular laptop screen as well as clear to allow for much of the screens brightness to shine through. Most touch screens suffer from degradation of the monitor's true brightness but the DuoSense engineers made sure to minimize that effect while still providing advanced touch screen laptop functionality.

Sony - Vaio PCG-F190 Review

A relative newcomer to the notebook PC market, Sony made a real splash last year with its sexy little Vaio portable. Aiming to build on the success of that product, the company has launched a couple of additions to the line-up. This one, the PCG-F190, is the most powerful of the Vaio models, based on a 366MHz Pentium II processor. There's also a 6.4GB hard drive and 64MB of SDRAM memory onboard, all of which means that this machine is considerably larger than its predecessor.

Dominating the case when you open the lid is the 14.1-inch TFT LCD screen, which is bright and sharp and offers plenty of workspace. Underneath this screen, which can handle a top resolution of 1024 x 768, is a keyboard whose keys are nearly all full-sized. Coupled with the large wrist-rest area, in which there's a track-pad mouse device, this means that touch-typing is a comfortable affair on the Vaio, although the notebook is probably a little too heavy to be used on the lap for very long.

Where the original Vaio lacked features, the PCG-F190 more than compensates. There's a built-in floppy drive, a built-in DVD-ROM drive, an i.Link (IEEE 1394) port for downloading still images from Sony's DV cameras, as well as USB and infra-red connectivity and a pair of PC Card (PCMCIA) ports. Sony includes a 56K PC Card modem with the notebook, and this can be upgraded to GSM, Ethernet and ISDN if required. Software supplied with the new Vaio includes a MiniDisc editor, video capture software, video editing software and Windows 98.

What is potentially more important than mere specifications, however, is the perceived and actual quality of this new notebook. In both respects, Sony has done well. The Vaio PCG-F190 looks every inch an expensive, stylish PC, with a design that sets it apart from most other notebooks in a very samey market. It feels pretty solid, too, with thick plastic used in most places, and no rattles or creaking noises from the case. And despite its comprehensive range of features and powerful processor, the battery life appears to be very good. The new range is backed by a one year warranty.

Sony - Vaio PCG-F190 features - Verdict

This proves that the original Vaio was not a one-off. Sony has taken its knowledge of consumer electronics and applied it to the notebook PC market, with impressive results. The Vaio PCG-F190 looks unique, feels well-made and performs as well as any other notebook on the market. It's clear evidence that Sony is giving the established players a great deal to think about.

Sony - Vaio PCG-F190 price

2559 + VAT

Sony: 0990 424424

www.sony-cp.com

Panasonic - ToughBook 71 Review

The adjective 'sexy' is usually reserved for supermodels, film stars and, occasionally, cars. To call a notebook sexy is, you'd have thought, taking things a little too far. But then, this is no ordinary notebook. The Panasonic ToughBook 71 has been designed to be a little more durable than the average plastic laptop. Intended for the large number of business users who rely on their portable computers and need them to survive the occasional knock, drop and coffee spill, the ToughBook 71 has several unusual features.

First, there's the case, which is made from magnesium alloy. Although light, this is (according to Panasonic) 20 times stronger than the ABS plastic used in the construction of most notebook PCs. That helps to protect the LCD panel and the internal components from the stresses of everyday life. Such as having a reclining aircraft seat smashing into it. Then there's the keyboard and touchpad mouse, which are both water resistant to cope with the occasional coffee spill. Finally, the protection extends to the 4GB hard drive, which is mounted in a polymer gel to prevent shock or vibration damage.

On the practical front, this notebook is based on a 266MHz Pentium II processor, with 32MB of memory that can be upgraded to a maximum of 160MB. There's a 2MB graphics adapter driving the 12.1-inch TFT LCD panel, the latter capable of a top resolution of 800 x 600. It's pretty bright, too, so using it in daylight is not much of a problem. In standard form, the ToughBook 71 is equipped with a 1.44MB floppy drive but no CDROM drive. You have to pay extra for that, but it can be conveniently used in place of the floppy drive while you're out on your travels. To use both together, you'll have to plug the floppy drive in externally, using the appropriate cable.

Love 'em or loathe 'em, touchpads are here to stay, and the ToughBook's is a pretty good example of the breed. It's reasonably sensitive, has a couple of buttons at the front and can even be used for capturing signatures using a pen. The keyboard is mostly full-sized and has a light feel that will appeal to touch-typists but not to the more heavy-fingered. Because the ToughBook 71 doesn't need a separate carry case, there's a strong metal handle built into the front. The whole package is backed by a three year parts and labour warranty.

Panasonic - ToughBook 71 features - Verdict

Protection comes at a price; you could buy a notebook of similar specification to this and still have several hundred pounds burning a hole in your pocket. But would it last as long? Unlikely. This is a strong, durable and fast notebook that also happens to look remarkably stylish and, yes, sexy. If that's what turns you on...

Panasonic - ToughBook 71 price

2,300 + VAT

Panasonic: 0500 404041

www.panasonic.co.uk

What Are RFID Tags?

Radio-frequency identification chips (often called RFID tags) are passive, inductively powered chips that are used for numerous applications, from substituting bar codes on supermarket products to discovering lost dogs and cats. It is a tiny, battery-powered electronic device that can be taken around to warn its possessor that a new RFID tag has been positioned in his or her locality or that his or her tags are presently being scanned. One of the introductory RFID TAG development companies, Alien Technology leads the industry in developing high-quality compliant RFID tags, readers and printers for companies worldwide. Once the RFID tag is activated, the tag decodes the incoming query and makes an proper reply by utilizing the energy of the incoming radio wave to power the chip long enough to reply.

Some other companies are using RFID for a large kind of applications. Some of these applications include: supply chain management, automatized payment, physical access control, counterfeit prevention, airline luggage management, and smart homes and offices. The following are the most common forms of tags: Label: The tag is a flat, thin, flexible form. Ticket: A flat, thin, flexible tag on paper .Card: A flat, thin tag embedded in tough plastic for long life. Glass bead: A small tag in a cylindrical glass bead, used for applications such as animal tagging (e. Assorted frequencies have different characteristics that make them more useful for several applications.)

RFID TAGS bring value and accuracy to many applications such as: Compliance labeling in retail distribution centers. High-speed processes in postal and parcel distribution. Manufacturing process control and verification, material tracking, Airline luggage identification and routing systems, and Single-pass multiple item identification. RFID technology can be utilized to raise productivity and tracking in discrete and process manufacturing. For RFID applications such as toll collection and vehicle and container tracking, the tags are used over and over for many years. The most usual applications are payment systems (Mobil Speedpass and toll collection systems, for instance ), access control and asset tracking. Active and semi-passive rfid tags are useful for tracking high-value goods that need to be read over long ranges, such as railway cars on a track, but they cost more than passive tags, which means they can t be utilized on low-cost items.

However, the ease with which RFID tags can be tracked opens up the door to invading people s privacy. The accelerated adoption of RFID technology has produced worries with some groups involved with privacy such as the Electronic Frontier Foundation and the American Civil Liberties Union . Civil liberties groups are afraid about RFID technology being abused to invade people s privacy; RFID tags enable unethical individuals to snoop on people and sneakily collect information on them without their approval or even knowledge.

RFID tag technology, a replacement to bar code technology, identifies tagged items over radio communication between an electronic reader and tags carrying data on microprocessor chips. The major disadvantages of a passive rfid tag are: The tag can be read only at very close distances, typically a few feet at most. Passive RFID tags are more suitable for warehousing surroundings where there is not a lot of interference, and comparatively short distances (typically ranging anywhere from a few inches to a few yards).

Welcome dual touch screen laptop technology

Dual touch screen laptop technology no longer sounds like concept device. An Italian company actually already released something similar in the Canova, a full dual-touch screen device, but we couldn't call it a laptop in its first generation form. The next product in line is predicted by some industry experts to be released in 2010, but the company behind the revolutionary product, V12 Design, is being tight lip about specifics over the dual touch screen laptop. The company has paired with an unnamed U.S. based laptop manufacturer in developing the laptop.

Features that are have been mentioned by the CEO of V12 as well as speculated by outsiders really sound like taking the best of today's smart phone technology, the computing power of today's laptops, and rolling it into a machine that will balance usability and mobility. There are promises that the new laptop, if we can call it that, will do things no one has ever seen a laptop do before. There will be support for multi-touch input and an on-screen software keyboard when applicable. There seems to be speculation that unlike other on-screen keyboards, such as the Apple iPhone and similar touch screen smart phones, the keyboard will use a special haptic feedback technology to give users better comfort and feel closer to a traditional keyboard.

As such, the software running on the new machine will be designed for minimal use of keyboarding and there will definitely be a built in microphone with voice recognition technology to a major degree. With the advancement in voice recognition technology, as well as dual touch screen, laptops of this design are expected to utilize voice activated commands much more than we're used to today.

With this must viewing surface you can imagine the possibilities laptop manufacturers can cram into these mobile computing machines. Expect the functionality from the first generation Canova to carry over. These would be the drawing and writing pad which is a pretty standard feature of most touch screen laptops. In addition to allowing for artistic expression, the new laptop will also transform into an ebook reader and the touch screen will allow for page flipping like a traditional book. Speaking of which, this is not the only dual touch screen notebook set to release. At about the same time, OLPC is promising to have realized its' concept laptop; looks like we have an exciting upcoming year.

Smartphone

Most of us are familiar now with cell phones. They ve been around long enough and we ve struggled with each new upgrade enough that they no longer mystify and exasperate the average user. So then along comes the smartphone. These go beyond what the typical cell phone can do and often act like computers. In fact, there is not one definition of a smartphone. Some run complete operating-system software and have a standardized interface and platform. In other cases, the smartphone simply has some capabilities that the standard cell phone doesn t have.

According to David Wood of Symbian, "Smart phones differ from ordinary mobile phones in two fundamental ways: how they are built and what they can do." However, nowadays most smartphones use an identifiable operating system such as Windows and usually are able to accept applications such as data processing software. The applications are sometimes developed by the manufacturer of the smartphone or can be made available by a third-party software developer with no connection to the manufacturer.

Most have e-mail capability and a personal organizer. A miniature QWERTY keyboard can be added. Also, some have touchscreens and built-in cameras. Other potential add-ons are contact management software; navigation hardware and software; PDF-reading capability; software for music, browsing photos, and viewing video clips; internet browsers; or secure access to company mail.

IBM developed the first smartphone in 1992 and called it Simon. It was shown as a concept at a computer industry trade show in Las Vegas that year. BellSouth sold it to the public in 1993. In addition to standard cell-phone features, it had a calendar, address book, world clock, calculator, note pad, e-mail, send-and-receive fax, and games. A touchscreen was used on this innovative new phone for selecting phone numbers. Faxes and memos could be created with a stylus using a "predictive" keyboard. Today it would be considered a low-end smartphone.

Nokia got into the smartphone revolution in 1996. Theirs was a palmtop computer and was based on a PDA model by Hewlett Packard and Nokia s best-selling phone. The Nokia 9210 had the first color screen and was the first true smartphone with an open operating system. The 9500 Communicator was Nokia s first cameraphone and first WiFi phone. The latest E90 Communicator has GPS. All of these new Nokias are very expensive.

Research in Motion (RIM) began marketing the first BlackBerry in 2001. It was the first smartphone optimized for wireless e-mail use. It has been very popular.

The first wildly popular smartphones in the United States were the Treo marketed by Handsprings in 2002, which eventually was bought out by Palm. Microsoft also announced its Windows CE Pocket PC OS that same year as Microsoft Windows Powered Smartphone 2002.

Nokia s N-Series of 3G smartphones were marketed in 2005 not as mobile phones but as multimedia computers.

Smartphones, the higher end of the camera phone market and having full e-mail support will account for about 10% of the camera phone market in 2008. One billion camera phones will be shipped this year.

Useful Tips to Maintain the Temperature of Your Notebook

Many notebook users neglect one of the most important aspects of using the gadget, i.e, protecting it from overheating. Maintaining the temperature of the laptop computers is another way of enhancing its performance. The user should know and understand the safest operating temperature for a notebook.

How to find the temperature:

The temperature of the laptop can affect the performance of the device. But, the prime aspect of consideration is to find the notebook temperature. Here are some of the useful ways how you find the notebook temperature so that you can avoid the causes responsible for overheat of the machine.

Usually the notebooks come with software to keep track of the temperature. While purchasing notebook, look for the utility software meant to find the notebook temperature. Generally, the software is not a part of the Operating System of the computer, but a part of software provided by the manufacturer.

Apart from the preinstalled software you can download free software from the Internet. They are available with instructions of using them and help you find the temperature of your laptop. Few laptop users with technical mind use thermal sensor to keep track of the temperature of their machines.

How to keep your notebook from overheat:

Now that you are able to find the temperature of your notebook, you have to take necessary steps to maintain the temperature and protect the machine from overheating to keep the machine cool. In fact, it is an effective and cost-effective way of increasing the notebook performance.

If you feel that your notebook is getting too hot, it is high time it needs a break. Shut down the machine and allow it to cool. Also, try to place your notebook on a flat surface. You can find rubber feet that allow airflow to the lower side of the notebook. When you are using the machine placing it on a bed or any other such surfaces chances are there your laptop may not get enough air.

Alternatively, you can work with your laptop placing it on your lap if want to work away from the desk to allow proper airflow. You can also place a towel underneath to avoid the heat. Also, try to raise your notebook from the surface allowing increase of airflow to the lower surface. You can even use a laptop stand to rest your laptop on it.

Many people keep their laptop on even after placing them inside the laptop case as it is convenient to take the machine out of the bag, open the screen and work immediately. But, the environment inside the notebook case is generally warm and it can get warmer with the already switched-on computer. It can cause harm to the hardware of your laptop. It is better to shutdown the notebook before placing it in the notebook case.

It is common among the laptop users to keep the computer plugged in throughout the working hours. The constant flow of electricity will not only reduce the performance of the battery but also increase the heat of the battery. It will eventually overheat the laptop. It is very essential to charge your computer as long as necessary, otherwise unplug the charger once the battery is full.

Another way you can keep your laptop from overheat is by buying a laptop cooler. Of course it is a pricey choice, but it can provide cool air to the underside of the notebook. Now, enhancing the performance of your notebook is in your hand. While using your notebook, make sure that it does not get overheat.

How to print a document using a Windows Vista printer

Printing a Document

The conventional way of printing a document is as follows:

1. Issue a Print command from the program that created the document or from a program designed to handle its file type.

2. Choose any relevant options which pages to print, or the resolution to use in the Print dialog box.

3. Click the Print button or the OK button.

Windows also lets you print directly to the printer from Explorer. You can print a document from Explorer by dragging it and dropping it on the printer in the Printers window or on a shortcut to the printer. Windows prints the document with default settings, so you don t get to choose any of the usual printing options. But usually you won t have the printer or a shortcut to it handy enough for this technique to be useful, although you can create shortcuts to a printer wherever you need them, such as on the Desktop. For this technique to work, the file must include the extension linked to the appropriate file type and program; otherwise, Windows doesn t know which program to use to print the file. Many programs support printing directly from Explorer and so include a Print command on the context menu for the document. To print a document, right-click it, and then choose Print from the context menu.

Managing Your Print Jobs

Once you ve sent a document to the printer, you can just wait for Windows to print it. If you re the only person using this printer, and if there s no problem with the printer such as being out of paper, ink, or toner, it should print more or less right away. But if you re printing many documents, or if you re sharing one or more printers with people who are printing many documents, you may find yourself needing to manage print jobs. This section discusses how to do so.

Dealing with a Print Job Gone Wrong

It s much easier, neater, and cleaner to cancel a job before it starts printing than after it starts printing - but often you ll only realize that you need to cancel a particular print job when the printer starts spewing out garbage - sheets of paper with only a single column of letters, or with mangled graphics, or page after page of PostScript codes instead of the layout of ink they re supposed to represent.

When you cancel a print job that s being printed, the printer may get confused. Give it a minute or two depending on the printer s speed to clear its memory of the interrupted job. If that doesn t work, you may need to reset the printer, by pressing a hardware reset button, by issuing a software reset command supported by the printer s custom software, or by turning the printer off and then back on again.

Pausing and Resuming Printing

To pause printing of all documents on the printer, right-click the printer in the Printers window, and then choose Pause Printing from the context menu. Alternatively, click the printer, and then click the Pause Printing button on the toolbar. To resume printing, right-click the printer and choose Resume Printing from the context menu. Alternatively, click the printer, and then click the Resume Printing button on the toolbar. On a network printer, you have only the privileges of a Guest user on that computer. This means that you can pause, restart, and delete only your own print jobs; you can t affect other people s print jobs.

Managing Print Jobs by Using the Print Queue

To cancel print jobs, or rearrange the order in which they print, use the print queue. To open the print queue by using one of the following methods:

If the notification area is displaying a printer icon for the printer, double-click the icon.

Double-click the printer in the Printers window, or click the printer, and then click the See What s Printing button on the toolbar.

From the print queue, you can take the following actions:

Cancel a print job Right-click the job in the print queue and choose Cancel from the context menu. Alternatively, choose Document Cancel.

Pause a print job Right-click the job in the print queue and choose Pause from the context menu. Alternatively, choose Document Pause.

Resume a paused print job Right-click the paused job in the print queue and choose Resume from the context menu. Alternatively, choose Document Resume.

Restart a paused or failed print job Right-click the paused or failed job in the print queue and choose Restart from the context menu. Alternatively, choose Document Restart.

Change priorities or time restrictions for a print job Right-click the job and choose Properties from the context menu. Windows displays the Document Properties dialog box for the print job. On the General page , drag the Priority slider to set the priority for the job, or use the controls in the Schedule text box to set or remove time scheduling. Click the OK button. Windows closes the Document Properties dialog box.

Troubleshooting Printing Problems

This section presents a general approach to troubleshooting printing problems. Given that there are about as many types of printers as there are types of cars, and that the drivers for those printers vary in quality even more widely than the drivers you ll encounter in a trip the length of Interstate 40, the information in this section is just a start - but if you persevere, you should find it can help you solve many problems.

Check Which Printer You re Printing To

If your computer is configured to connect to more than one printer, make sure that you re printing to the printer you think you re printing to. Few things are more irritating than wasting time troubleshooting an innocent and fully functional printer only to find that you ve printed out five copies of the same secret document on another printer - and your colleagues have found them. Given that the Print dialog box shows you which printer you re using, this problem is most likely to occur when you issue a Print command that starts the print job without displaying the Print dialog box.

Make Sure the Printer Is Working

Next, make sure the printer is working. Check that it s

Powered on. Not set to be offline or paused. Loaded with ink and paper, and not jammed. Connected to the computer, print server, or network. If another computer or a print server is involved, check that it s powered on and functional.

Check the Program You re Printing From

If all is well with the printer, make sure you re not doing something wrong in the program from which you re trying to print. In particular, check that you re trying to print the right part of the document. For example, in a spreadsheet, make sure you haven t defined a print area that has the wrong contents. In a multipage document, check that you re trying to print the correct pages.

Running the Printing Troubleshooter

If the previous approach doesn t lead you to fix the problem, you can run Windows s Printing Troubleshooter and have it walk you through the steps of troubleshooting the problem:

1. Choose Start Help And Support. Windows displays a Windows Help and Support window.

2. Type troubleshoot printer problems in the Search box, and then press Enter. Windows displays a list of results.

3. Click the Troubleshoot Printer Problems link, and then follow its suggestions.

Configuring Your Print Server

Apart from the printer, which you saw how to configure earlier in this article, you can also configure the Windows print server - the software that controls the printers attached to your computer. In most cases, the default print server settings work fine, but you can improve your computer s performance and the printing experience of your print server s clients by setting the appropriate options. In particular, you may want to move the print server spool folder to a different location than its default location.

Opening the Print Server Properties Dialog Box

To set print server properties, open the Printers window, right-click in open space in the document area where the printers are listed, right-click open space rather than one of the printers, choose Run as Administrator Server Properties from the context menu, and then authenticate yourself to User Account Control. You can also simply choose Server Properties if you want to view the properties without having permission to set all of them. Windows displays the Print Server Properties dialog box, which contains four pages: Forms, Ports, Drivers, and Advanced.

Creating Custom Forms on the Forms Page

The Forms page of the Print Server Properties dialog box lets you create a new form. Take the following steps:

1. In the Forms On list box, select the existing form on which you want to base the new form.

2. Select the Create a New Form check box.

3. Type the name for the form in the Form Name text box.

4. Use the fields in the Form Description group box to specify the dimensions of the form, its margins, and the measurement units to use Metric or English.

5. Click the Save Form button. Windows saves the form and adds it to the Forms On list box. To delete a form you ve added, select it in the Forms On list box, and then click the Delete button. Windows doesn t allow you to delete the built-in forms.

Configuring Ports on the Ports Page

On the Ports page of the Print Server Properties dialog box , you can add new ports, configure existing ports, and delete ports you don t need anymore. The port configuration options available depend on the type of port involved - printer port, serial port, COM port, print server port, and so on. See the section Setting Ports Page Options, earlier in this article, for a discussion of the different port types and the options you can set.

Working with Printer Drivers

The Drivers page of the Print Server Properties dialog box lets you add new drivers, check the properties of existing drivers, replace existing drivers, or delete existing drivers. Normally, if you ve set up one or more printers for printing on your computer, and they re printing correctly, you shouldn t need to make changes here. But you may need to make changes if:

You share printers on the network with other computers that use different processor types or operating systems - for example, Itanium processors or 64-bit versions of Windows.

You ve removed a printer from your computer. Windows leaves the driver on your computer in case you need it again. If you don t, you can remove it using the Drivers page.

Adding a Driver for Another Processor Type or Operating System

To add a driver, follow these steps:

1. On the Drivers page of the Print Server Properties dialog box, click the Add button. Windows launches the Add Printer Driver Wizard, which displays its Welcome screen.

2. Click the Next button. The wizard displays the Printer and Operating System Selection screen .

3. Select the check box for each processor type or operating system used by a computer on your network that will print using a printer on this computer.

4. Click the Next button. The wizard displays the Printer Driver Selection screen. This screen has the same controls and works in the same way as the Install the Printer Driver screen of the Add Printer Wizard, earlier in this article.

5. Select the printer s manufacturer in the Manufacturer list, and then select the model in the Printers list. You can also click the Have Disk button to supply a driver that you have on a disk.

6.Click the Next button. The wizard displays the Completing the Add Printer Driver Wizard screen.

7. Click the Finish button. The wizard installs the driver and closes itself.

Removing a Driver

To remove a driver, take the following steps:

1. Select the driver in the Installed Printer Drivers list box on the Drivers page of the Print Server Properties dialog box.

2. Click the Remove button. Windows displays the Remove Driver and Package dialog box, shown here.

3. Select the Remove Driver Only option button if you want to remove only the driver. If you want to remove the driver and its package, select the Remove Driver and Driver Package option button.

4. Click the OK button. Windows displays a confirmation dialog box, as shown here.

5.Click the Yes button. If you re removing the driver package as well as the driver, Windows displays the Remove Driver Package dialog box, shown here.

6. Click the Delete button. Windows removes the item or items.

7. Click the OK button. Windows closes the Remove Driver Package dialog box.

Choosing Advanced Print Server Options

The Advanced page of the Print Server Properties dialog box contains the following settings:

Spool Folder text box The spool folder is a folder on your hard drive in which Windows stores the spool files for print jobs as they re being printed. Windows spools the data so that it can return control more quickly to the program that sent the print job. Spool files can be large, particularly for graphical documents, so you may want to move the spool folder to a drive that has plenty of space. The default location for the spool folder is on the partition that contains the Windows system files, but Windows will perform better if you move the spool folder to a different partition.

Log Spooler Error Events Select this check box to make Windows write printer error events to the System log. This behavior is usually helpful.

Log Spooler Warning Events Select this check box to make Windows write printer warning events to the System log. This behavior too is usually helpful.

Log Spooler Information Events Select this check box to make Windows write printer information events to the System log. You probably don t need printer information such as details on each document that was printed successfully cluttering the System log.

Beep on Errors of Remote Documents Select this check box to make the print server beep when an error occurs when printing a document from another computer.

Show Informational Notifications for Local Printers Select this check box to make Windows display notification-area information pop-ups when the computer is printing to a local printer or a stand-alone network printer. If the printer is attached to the computer, these notifications usually don t help the user.

Show Informational Notifications for Network Printers Select this check box to make Windows display notification-area information pop-ups when the computer is printing to a printer attached to another computer. This behavior is usually useful.

Select the Print to File check box in the Print dialog box

Printing Offline

If you re working offline, or if you want to queue up a number of print jobs and let them all run at once, put the printer offline. To do so, right-click the printer in the Printers window, and then choose Use Printer Offline from the context menu. You can then print to the printer as if your computer were connected to it, but instead of sending the data to the printer, Windows holds it in the print queue and saves it to disk. When you ve reconnected to the printer or when you want to print, if you didn t disconnect, right-click the printer in the Printers window, and then choose Use Printer Online. Windows starts sending the print jobs to the printer. The printer must be a local printer - you can t print offline to a network printer.

Creating Multiple Entries for the Same Printer

If you want to use the same printer regularly in different ways, you can create two or more entries for it in the Printers window, and then set different properties for each entry. For example, you might set one printer entry to have a higher priority than the other, and then use that printer entry yourself while assigning the lower-priority printer entry to other users. To create a new entry for the printer, install it again using the technique described earlier in this article. When you install the printer again like this, the Add Printer Wizard displays the Which Version of the Driver Do You Want to Use? screen, which offers you a Use the Driver That Is Currently Installed option button and a Replace the Current Driver option button. Given that the driver is the same, leave the Use the Driver That Is Currently Installed option button selected, and then click the Next button. On the Type a Printer Name page, assign the printer a name that reflects the role you plan for it. For example, if you create a new entry for a printer so that you can use it to print to a file, include that information in the printer s name and perhaps add it to the printer s Location and Comment fields as well. After installing the printer, set properties for it to play the role you intend.

Printing to a File

Sometimes you may want to print a document to a file that you can send to someone else for printing or that you can use in another program. For example, if you need to have a document printed on a high-resolution device in your local print shop, you can print the document to a file, put the file on a portable medium, and take it along to the print shop. That way, the print shop doesn t need to have a copy of the program that created the document, the way it needs one if you copy the document onto a removable disk or recordable CD and take that along to the print shop instead. You can print to a file in any of three ways:

Select the Print to File check box in the Print dialog box When you print from a

program, you can select the Print to File check box in the Print dialog box to print a particular job to a file rather than to a printer.

Configure a printer to always print to a file By configuring a printer always to print to a file, you can turn every job you send to that printer into a print file.

Print to XML Paper Specification By printing to Windows XPS format, you can create a file that will look the same on any computer with an XPS viewer. All versions of Windows Vista include an XPS viewer.

Another Means of Printing to a File: Portable Document Format PDF

If you often need to print to a file, or if you need to make read-only versions of documents and retain their layout, another option is to buy Adobe Acrobat. Acrobat produces documents in Portable Document Format PDF, which you can view on most computer operating systems using the free Acrobat Reader, which is available from the Adobe website. Acrobat is more expensive than printing to a file, but in many cases it produces better results with service bureaus than simply printing to a file.

If you have Microsoft Office 2007, you can download from Microsoft s web site a component that allows the Office 2007 programs to create PDF files.

Printing to a File from the Print Dialog Box

To print to a file from the Print dialog box, follow these steps:

1. Issue a regular Print command as usual. For example, choose File Print or press Ctrl+P. Windows displays the Print dialog box.

2. Select the Print to File check box.

3. Choose any other appropriate printing options as usual for the program.

4. Click the OK button or the Print button, depending on the program. Windows displays the Print to File dialog box, as shown here.

5.Type the filename for the print file. If you want to specify the folder in which the print file is saved, enter the path to the folder before the filename. Otherwise, Windows saves the print file in the program s current folder.

6. Click the OK button. Windows closes the Print to File dialog box and the Print dialog box and prints the document to the file. Windows gives the file the .prn extension.

Setting a Printer to Always Print to a File

You can also set up a printer so that it prints to a file every time and doesn t let the user print to a physical printer. This capability is useful when you always need to create print files on a particular printer and don t want to risk actually printing a document by forgetting to select the Print to File check box in the Print dialog box, or if the printer in question is never available from your computer. To make a printer always print to a file, select the FILE port in the Print to the Following Ports list box on the Ports page of the Properties dialog box for the printer. Windows clears any other port selected for the printer unless you ve selected the Enable Printer Pooling check box. When you click the OK button and Windows closes the Properties dialog box, Windows displays a disk on the printer icon to indicate that the printer is set up for printing to a file.

Setting Print to File as Your Default Printer

If you spend a lot of time on the road or in your local coffee shop, out of reach of any printer, you may want to set Print to File as your default printer. If you do, give the virtual printer an easy-to-remember name so that you don t have to guess whether you re printing to a real printer or not.

Printing to an XPS File

To print to an XPS file, follow these steps:

1. Issue a regular Print command as usual. For example, choose File Print or press Ctrl+P. Windows displays the Print dialog box.

2. In the list box or drop-down list for selecting the printer, choose the Microsoft XPS Document Writer item.

3. Choose any other appropriate printing options as usual for the program.

4. Click the OK button or the Print button, depending on the program. Windows displays the Save As dialog box.

5. Choose the folder in which to save the XPS file, and assign it a filename.

6. Click the Save button. Windows creates the XPS file.

Windows Vista: Configuring Pen and Input Devices Settings

To configure Pen and Input Devices settings, first open the Pen and Input Devices dialog box. If you opened it in the last step of the previous section, you re all set. Otherwise, take the following steps:

1. Choose Start Control Panel. Windows displays a Control Panel window.

2.In Control Panel Home view, click the Hardware and Sound link. Windows displays the Hardware and Sound window.

3. Click the Pen and Input Devices link. Windows displays the Pen and Input Devices dialog box.

Configuring Pen Options

The Pen Options page of the Pen and Input Devices dialog box lets you change how Windows interprets actions you take with the pen and what effect clicking the pen buttons has. Windows doesn t let you customize the effect of a single tap, which it always reads as a single click. But you can change the definition of a double-tap which represents a double-click and a press-and-hold gesture which represents a right-click, and you can set up a gesture for starting the Tablet PC Input Panel.

Customizing a Double-Tap

To customize a double-tap, follow these steps:

1. Click the Double-Tap item in the list box, and then click the Settings button. Windows displays the Double-Tap Settings dialog box .

2. Drag the Speed slider left or right to decrease or increase the speed required to generate a double-tap.

3. Drag the Spatial Tolerance slider left or right to decrease or increase the distance Windows allows the pointer to move between taps in a double-tap. If the pointer moves too far, Windows doesn t register the double-tap.

4. In the Test Settings area, double-tap the graphic to make sure that you ve chosen suitable settings. Windows changes the graphic when it registers a double-tap.

5. Click the OK button. Windows closes the Double-Tap Settings dialog box.

Customizing a Press-and-Hold Gesture

To customize a press-and-hold gesture, follow these steps:

1. Click the Press and Hold item in the list box, and then click the Settings button. Windows displays the Press and Hold Settings dialog box .

2. Select the Enable Press and Hold for Right-Clicking check box if you want to be able to rightclick by pressing and holding down the stylus.

3. Drag the Speed slider left or right to decrease or increase the speed with which Windows registers a press-and-hold gesture when you press the pen tip down and hold it there.

4. Drag the Duration slider left or right to decrease or increase the length of time that Windows allows you to perform a right-click action.

5.In the Test Settings area, press and hold the graphic to make sure that you ve chosen suitable settings. Windows changes the graphic when it registers the press-and-hold gesture.

6. Click the OK button. Windows closes the Press and Hold Settings dialog box.

Defining a Gesture for Starting the Input Panel

To define a gesture for starting the Tablet PC Input Panel, follow these steps:

1. Click the Start Tablet PC Input Panel item in the list box, and then click the Settings button. Windows displays the Start Input Panel Gesture Settings dialog box, as shown here.

2. Select the Enable Start Input Panel Gesture check box if you want to be able to use a gesture to start the Input Panel.

3. Drag the Gesture Setting slider left or right to decrease the size of gesture you need to perform to start the Input Panel.

4. Hold your pen a short distance from the screen, and then move it quickly from side to side. If Windows doesn t recognize the gesture, adjust the Gesture Setting slider.

5. Click the OK button. Windows closes the Start Input Panel Gesture Settings dialog box.

Choosing Settings for the Pen Buttons

In the Pen Buttons group box, choose settings for the buttons on the pen you re using with your Tablet PC:

Use the Pen Button as a Right-Click Equivalent Select this check box if you want to rightclick by clicking the pen s button. Many people find clicking the pen s button much easier than performing the press-and-hold gesture.

Use the Top of the Pen to Erase Ink Where Available Select this check box if you want to use the top of the pen if it has a suitable top to erase ink.

Configuring Pointer Options

The Pointer Options page of the Pen and Input Devices dialog box lets you choose whether to have Windows provide feedback for pen taps and clicks and whether to display pen cursors:

Dynamic Feedback In this group box, select the check box for each action on which you want Windows to give you visual feedback: Single-Tap, Double-Tap, Press the Pen Button, and Press the Pen Button and Tap. The circular symbols next to the check boxes show the feedback icons.

Pointer Options Select the Show Pen Cursors instead of Mouse Cursors When I Use My Pen check box if you want Windows to show pen cursors when you re using your pen. This option is usually helpful.

Configuring Flicks Options

The Flicks page of the Pen and Input Devices dialog box lets you specify whether to use flicks, pen gestures for navigation and editing, and configure the sensitivity for recognizing flicks:

Use Flicks to Perform Common Actions Quickly and Easily Select this check box to use flicks. If you don t want to use flicks, clear this check box to stop Windows from attempting to identify flicks in your pen movements.

Navigational Flicks/Navigational Flicks and Editing Flicks Select the option button for the type of flicks you want to perform. If you select the Navigational Flicks option button, you can use flicks only for Back flick left, Forward flick right, Drag Up flick up, and Drag Down flick down actions. If you select the Navigational Flicks and Editing Flicks option button, you can click the Customize button and use the Customize Flicks dialog box to customize the action for each flick.

Sensitivity Drag the slider along the Relaxed Precise spectrum to adjust how easily Windows recognizes your flicks. A setting toward the Precise end is usually best, as it prevents Windows from recognizing flicks that are in fact unintentional movements.

Display Flicks Icon in the Notification Area Select this check box if you want Windows to display a Flicks icon in the notification area that you can use to access the Flicks options.

Closing the Pen and Input Devices Dialog Box

Click the OK button. Windows closes the Pen and Input Devices dialog box and applies your choices.

Choosing Presentation Settings

If you use your computer to give presentations, you can benefit by configuring Windows Vista s presentation settings. To do so, follow these steps:

1. Click the Power icon in the notification area, and then click the Windows Mobility Center link in the pop-up window. Windows displays the Windows Mobility Center window.

2. Click the icon in the Presentation Settings box. Windows displays the Presentation Settings dialog box .

3.Clear the I Am Currently Giving a Presentation check box unless you re just about to give a presentation.

4. Select the Turn Off the Screen Saver check box if you want Windows to prevent the screen saver from starting during a presentation. Suppressing the screen saver is usually a good idea.

5. If you want Windows to automatically use a predetermined volume, select the Set the Volume To check box, and then drag the slider to a suitable position along the Low High axis. This feature is designed to help you avoid starting a presentation with unsuitable volume settings left applied from your previous task.

6. If you want to use a particular background image, select the Show This Background check box, and then select the image. You can either choose one of Windows images from the list box or click the Browse button and use the Browse dialog box to locate an image anywhere on your computer. Once you ve chosen the image, look at the preview, and choose a different setting in the Position drop-down list if necessary. The options are Center, Tile, and Fit to Screen, just as for a desktop background image.

7. If you use the same external monitor for presentations, connect it to your computer, and then click the Connected Displays button. Windows displays the Current Displays dialog box, as shown here. Select the I Always Give a Presentation When I Use This Display Configuration check box, and then click the OK button. Windows closes the Current Displays dialog box, returning you to the Presentation Settings dialog box.

8.Click the OK button. Windows closes the Presentation Settings dialog box, returning you to the Windows Mobility Center window.When you re ready to start presenting, click the Turn On button in the Presentation Settings area. Windows puts your presentation settings into effect and displays the Presentation Settings Are On icon in the notification area.

To turn off Presentation mode, click the Presentation Settings Are On icon, and then choose Stop Presentation from the menu, as shown here. Alternatively, click the Turn Off button in the Presentation Settings area in Windows Mobility Center.

Connecting an External Monitor

To give yourself more space for your work than your laptop s screen can provide, you can connect an external monitor. Windows lets you display information on an external monitor in three ways:

Extend your desktop Extending lets you use both your laptop s screen and the external monitor, displaying a different part of your desktop on each.

Mirror your desktop Mirroring lets you display the same information on the external monitor as on your laptop s screen. Mirroring is mostly useful for presentations.

Use only the external monitor Using only the external monitor lets you treat your laptop like a desktop. When you do this, you ll probably want to attach an external keyboard and mouse to your laptop. To connect an external monitor to your laptop, follow these steps:

1. Connect the monitor to a power source and to your laptop s graphics port, and then switch the monitor on.

2. Windows normally detects the external monitor and displays the New Display Detected dialog box . If Windows doesn t detect the monitor, open Windows Mobility Center and click the Connect Display button to make Windows scan for the monitor.

3. In the Extend Your Desktop area, select the Right option button or the Left option button to tell Windows whether you ve placed the external monitor to the right of your laptop s screen or to the left. This setting applies only if you re extending the desktop.

4. Below the two screens, select the Duplicate My Desktop on All Displays option button if you want to mirror your desktop on the displays. Select the Show Different Parts of My Desktop on Each Display if you want to extend your desktop as is most likely. Select the Show My Desktop on the External Display Only option button if you want to use only the external display.

5. If you re extending your desktop and have placed the external monitor above or below your laptop s screen, or if you need to change the resolution or refresh rate, click the Display Settings link. Windows opens the Display Settings dialog box, in which you can adjust the displays as discussed in the section Setting Up and Using Multiple Monitors in Article 13.

6. Click the OK button. Windows closes the New Display Detected dialog box, and you can start using the external display.

Wall Street Journal Releases Free iPhone App

The Wall Street Journal's new iPhone App, which offers news, podcasts and video, is also being offered for free. This could be a bit of an unpleasant shocker for online Journal readers, who have been paying more than $100 for their annual subscription, but a free iPhone application would put the Journal on even footing with The New York Times and other news sites that have released free Apps for news junkies.

The Wall Street Journal released a free Apple iPhone App that features breaking news, video, radio podcasts and customized navigation. The price point will perhaps come as a surprise to Journal readers already paying more than $100 per year for an online subscription to the paper.

A similar free application already exists for the BlackBerry, which is no surprise given that device s business-user orientation.

The decision to release its news content for free is particularly ironic given Journal Editor Robert Thomson s April 6 comments to The Australian.

In an interview with that newspaper, Thomson said, "It's certainly true that readers have been [socialized] wrongly I believe that much content should be free."

He further said that sites devoted to aggregating free news content "are best described as parasites or tech tapeworms in the intestines of the internet."

However, The Associated Press, ABC News, The New York Times and other news outlets offer similar iPhone Apps at no cost, suggesting that decision makers at the Wall Street Journal felt seizing mobile market share would be more of an uphill battle if they charged for their own application.

Those Journal decision makers may also see iPhone App users as falling into a different category of reader than its subscribers, minimizing the potential for cannibalization. While the iPhone has been making inroads into the enterprise, it is still viewed by many as a consumer, as opposed to a corporate, device.

As print media have suffered through their own upheavals and users increasingly receive their news online, questions have arisen over how much leeway third parties have to collect and disseminate news corporations content.

The AP announced on April 7 that it plans to start aggressively hunting down unauthorized users of its online content. Google says that it has already struck a deal with AP over distributing content on Google News, but other sites may not be so fortunate.

Google was previously a target in 2006 of a $17.5 million copyright-infringement lawsuit by Agence France-Presse. That suit was eventually settled out of court.

Apples Pages 08 is All Grown Up

Apples Pages 08 is All Grown Up

Review: Warts aside, Apple's word processor refresh is worth a look from current and prospective iWorkers alike.With the latest release of Apples office productivity suite, iWork 08, the Pages application moves into the ranks of full-fledged word processing applications.

Previously known more for its page layout capabilities than for its word processing capabilities, Pages now enables users to switch seamlessly between writing and designing documents.

In addition, the application offers 140 document templates and a snazzy track-changes feature, both of which work to position iWork 08 as an apt rival to Microsofts Office 2004 for Mac in the OS X-compatible office productivity arena.

However, Pages still has a way to go before it can displace the well-entrenched Microsoft Word and hold off the up-and-coming slate of Web-based word processors such as Google Docs in the all-important areas of file format compatibility and document collaboration. For one thing, documents stored in Pages default format can not be attached to e-mail messages without first compressing them or converting them to .DOC or PDF format.

I also encountered issues with file format conversion when exporting and importing Microsoft Office documents, which wasnt a surprise, since every non-Microsoft application that consumes Offices black-box binary file formats seems to encounter at least some level of mistranslation.

Pages does offer Microsoft OOXML (Office Open XML) support functionality that Microsofts Office 2004 for Mac notably lacks however, I found this support to be incomplete. It lacks, for example, a complete form component and field support. Companies that are standardizing on Office 2007s new formats should pay particular attention to these issues before relying on Pages to fill in the format support gaps in Office 2004.

Even with Pages warts, the application refresh should be welcome for current iWork users, and other OS X users would do well to download the evaluation version of Apples suite to try it out for themselves.

iWork 08 is reasonably priced, at $79 (or free with the purchase of any new Mac computer). The suite requires Mac OS X version 10.4.10 or later.

Perusing Pages

The first thing I did when testing the new version of Pages was check out the newly-separated modes for page layout and word processing. Previously, Pages shoehorned all word processing operations into the applications page layout mode, which as one would expect was a more comfy fit for piecing together newsletters and brochures than it was for writing letters and the like.

When I opted to open a new file in Pages, the program launched its template browser, which grouped the templates under the Word Processing subhead, or the Page Layout subhead. I chose to open both a new, blank word processing document and a new, blank page layout document. Both documents opened on the same screen, and I was able to toggle between each respective document mode with the greatest of ease.

The next feature I took to task was Pages new track changes feature, which is a collaboration capability for many companies. I found Pages version of this feature very handy. As I made changes to a document, caption boxes appeared in the documents margin describing the changes I had made, with arrows that connected these boxes to the text passages to which they referred.

I could click on an "X" icon within each box to dismiss the changes, or click on a checkmark icon to approve the change. Deleted phrases appeared as such with a strikethrough key, and changed text appeared in a different color to distinguish it from the unchanged text.

This feature is also compatible with Microsoft documents, so changes I made to a .doc file got the same treatment. No matter how many changes I made to the document, the track changes feature always kept the document looking clean and readable.

Modern Computer Filters Offer Simple, Low-Cost Dust Protection

Computer filters

provide dust and dirt protection for your PC. A common concern is that adding a computer filter to the air inlet port near the power supply fan may do little to block dust and dirt from entering the computer unit. Modern computers have numerous internal fans and it is often difficult to differentiate between the air intake and exhaust. Some fans are used just to circulate internal air. A simple computer filter on the back of a PC is not going to work for the long term.

A better computer filter solution is a breathable filter bag that covers all inlet and outlet ports of a computer unit but still allows the computer to be cooled properly. Modern dust bag style computer filters protect the entire unit from dust, dirt, and other airborne contaminants. They are designed in sizes to fit virtually any computer tower

and can be installed in minutes. They work well for monitors and printers as well, both of which need clean filtered air to assure proper long-term operation.

Computer filters used on computer cabinets also do a poor job protecting your computer from dust and dirt in the long term. One reason is because most computer cabinets require you to open the cabinet to operate the computer, for instance to access the CDROM or floppy drive. These operational requirements allow dust to bypass the cabinet dust filter and traps dust within the cabinet which eventually will be pulled inside the PC and settle there. This is completely preventable with a dust bag filter.

It is very important to use computer filters with PCs used in industrial or workshop situations where dust and dirt can very rapidly reduce the reliability and lifespan of the computer. Critical computer components exposed to dust and dirt, particularly the mechanical components like the keyboard and CD-ROM, can cease to operate without warning, and many times cannot be repaired once damaged by these contaminants. Studies have shown that dust can fill an unprotected computer in a matter of days, causing it to overheat. And metal dust can cause circuits to short-out, introducing a new workshop hazard. Dust bag style computer filters can do a lot to minimize these issues.

A problem with traditional computer filters is that they are designed to capture dust without impacting the amount of air that can enter the computer for cooling. This requires them to be fairly porous with the filter designed to capture the larger dust particles and allowing smaller dust particles and other airborne particles to pass through. The small surface area of the standard filter means that the air-flow must be relatively high, and dust and dirt collecting in the filter material quickly begins to restrict air flow. This problem is ameliorated by the larger dust bag, where the huge surface area of the filter translates into lower air-flow speed and a larger area to spread the dust trying to enter the computer. The lower air-flow speed also ensures less dust makes it through the filter material, especially smaller dust particles and airborne mists.

A small investment in a dust filter can provide a level of insurance that your computer equipment will operate when you need it to, and not wear out before its time. Dust bag style computer filters are especially effective, easy to install and inexpensive.

Speed up your PC with more Memory

One of the factors that will determine how fast your PC runs is the amount of RAM (Random Access Memory) that is in your system. The reason for this is because if you have a small amount of memory for the application programs

you are running, the PC will be spending time (processor time) swapping information in and out of the limited amount of memory to your hard drive. Processor time spent swapping data in and out of memory is time that could be spent performing the activities of your running applications. If more memory is added to the system (assuming space is available) then more applications and or their data can remain in memory, reducing the amount of time wasted swapping information in and out of memory.

If your PC is a few years old and now appears to be running slower than it did when it was new, this is probably because new software or software upgrades that you have added to the system are putting evermore demands on the available memory.

If you want to get some idea if memory might be a problem for your slow PC, then check your PC s RAM usage by opening the Windows Task Manager. You can start the Task Manager by pressing Ctrl-Alt-Del at the same time () and then click the Performance tab. If the figure next to Available (or Free in Vista) in the Physical Memory section is getting close to zero, for example if only 10% or so of your PC memory is available, you probably need more RAM.

In general a standard Windows XP user will find that 1GB of RAM should give them satisfactory system performance. For users who run lots of demanding applications simultaneously or they do a lot of working with digital video or other large graphics files then they should have 2GB of RAM or more.

If you are planning to upgrade your PC to run Windows Vista, you can run this operating system with 1GB of RAM, but for a better Windows Vista experience then 2GB of RAM is recommend.

Having decided that you need to increase the amount of RAM in your system to improve its performance you then have the following questions to answer:-

1. Are there any empty memory card slots available in your system?

2. Will I have to remove some of the current memory to make room for new memory?

3. What type of memory does your system require?

4. Is your PC using dual-channel memory, if so then you must install a pair of memory cards for maximum performance?

You could read your PC s manual to answer these questions and others, but the easiest thing to try first is to surf to one of the reliable RAM manufacturer s website using the PC you wish to upgrade. The main RAM supplier websites have online tools for identifying the right RAM for the PC you are using to surf to their website. These tools can tell you what memory you are currently using, if you have any empty memory slots and what upgrade options are available.

Using these online tools can clearly show you your upgrade options and really helps your to know that you are buying the correct memory for your system.

When you receive your new memory you will then have to read your PC manual to understand how to open up your PC and correctly insert the new memory. One thing you should be aware of when handling memory is that static electrical can damage these memory items and your PC s other delicate circuits. That is why you should read your manual as it should explain that you must earth yourself to the metalwork inside your PC, before removing your new memory from its protective covering and adding or removing items inside your PC.

Britec - Basic Facts about Spyware

Fact 1:

Spyware can easily be installed on a system without a user s knowledge. Infections can originate from open ports in your firewall or by not having a firewall, visiting some malicious websites or installing some software that includes the spyware with its install package.

In many cases one infection can propagate more infections by installing other spyware software in the background without the user ever knowing something is going on.

Basis of this Fact:

It only takes one open port in your firewall or just one piece of software to infect your system. After that most spyware is designed to download and install other pieces of software to infect and re-infect your system with even more spyware.

Fact 2:

There is no software available that can remove 100% of all spyware.

Basis of this Fact:

In a recent studies by PC world and others, tests compared 9 of the top spyware scanning and removal applications against each other. Each application was tested on a system infected with common spyware threats, and then compared against each other to see which product was best at spyware removal and detection.

The top three applications detected only 65% to 85% of the spyware on the test system, while all the other application detection rates were well below 60%.

So trusting just one piece of software for spyware removal is not a good bet.

Fact 3:

Spyware can make your identity information just a few mouse clicks away for criminals.

Basis of this Fact:

Spyware has helped many criminals get personal information in just a click of the mouse. A special type of spyware called a key logger can record your account numbers and passwords and then send them off to the writer of the spyware program on your system. Online Identity theft and fraud now leads the way as the method of choice to rip people off as it is simple to do and the chances of getting caught are small.

Fact 4:

Spyware can slow down your internet speed dramatically.

Basis of this Fact:

Every piece of information that leaves your computer via the Internet has to use some of your bandwidth. A heavily infected system can send a significant amount of information out at any given time.

This seriously limits the availability of bandwidth for legitimate uses and the user suffers a dramatic loss of speed.

In many cases, spyware can turn your computer into nothing more then a zombie that relays things like spam and viruses which uses even more system and bandwidth resources.

Fact 5:

Spyware takes away precious system resources from your computer, making boot times longer and overall performance much slower.

Basis of this Fact:

This is self explanatory. Your system only has so many resources available to complete tasks. Every program (good or bad) requires system resources; spyware takes away resources from legitimate computer programs.

Fact 6:

A survey suggests that over 90% of computers are infected with some type of spyware.

Basis of this Fact:

90% sounds like a lot, but imagine all the stuff your computer does day in and day out. All the websites you go to and all the programs you may have downloaded. So when you know that it only takes one bad website or one bad program to infect you and then you add up all the places you could get spyware from 90% is not that surprising.

Fact 7:

Some types of spyware can install programs to allow hackers complete control over your system.

Basis of this Fact:

Everyday users are having their systems hijacked and used to create problems. This often results in someone from the outside using your computer to send out spam and viruses or linking with thousands of other computers to shut down websites and launch other kinds of attacks.

What can I do to protect my system?

* Run more than one spyware scanner on your system.

As stated above no scanner catches 100% of all spyware so running more than one scanner increases the chances of catching spyware on your system.

* Scan often.

Scanning often makes sure you get rid of spyware before it has a chance to download more spyware or send your personal data out.

* Keep your system updated.

Make sure you have auto updates turned on or go to Windows update often so you get the latest security patches.

* Do not go to websites or download programs you are not sure of.

You can use the new phishing filter in IE7 to check websites and do a Google search for any new programs to check if they have been reported for spyware before downloading and using them.

How Large, How Fast? Choosing the Right Hard Drive Size and RPM

One necessary and extremely important component of computers is the hard drive. The hard drive stores your games, applications, music, pictures, videos, and documents. As such, you should be sure the notebook computer you re thinking of buying has a hard drive that can give you the storage and performance that you need.

There are two important considerations when looking at hard drive specifications for your computer notebook

: hard drive size and hard drive RPM.

Hard Drive Size

Hard drive size simply refers to the data storage capacity of a hard disk drive. Desktop computer hard drives offer sizes of up to 500 gigabytes (GB), while notebook computer hard dives offer sizes of up to 160 GB. Notebook computer hard drives are more expensive than desktop computer hard drives with more than twice the capacity of the notebook hard drive. This is due to the engineering difficulties inherent in making high-capacity hard drives for the smaller notebook computers form-factor.

A notebook computer s hard drive size indicates how much data a notebook computer can store. If you are interested in storing large amounts of movies, pictures, or music, you want to go with a larger hard drive to avoid running out of space.

A hard drive s size has very little to do with its performance, unless the drive is almost full. The Windows NTFS File System requires a minimum of 10% of the hard drive to be free space for optimum performance, and it frequently requests as much as 15%. This means that, on a 40 GB drive, Windows prefers that you use a maximum of 34-36 GB, leaving 4-6 GB of space unused. On a 160 GB drive, Windows prefers that you use a maximum of 136-144 GB, leaving a massive 16-24 GB unused. If you start to go over these Windows storage limits, you may notice your computer s performance taking drastic hits.

Hard Drive RPM

Hard drive RPM is a hard drive s rotational speed, measured in revolutions per minute (RPM). Desktop hard drives now have speeds as high as 15,000 RPM. Notebook hard drives, on the other hand, currently have an RPM ceiling of 7200 RPM.

A hard drive s RPM indicates how fast the drive s spindle will move or how fast the hard drive platters will spin. The higher the spin rate is, the shorter the seek time and latency will be. This translates to quicker data access and transfer.

How Large and How Fast

The greater the free space and the higher the RPM, the better your notebook computer s performance will be, so go for a slightly-more-than-comfortable size and the highest RPM for your notebook computer s hard drive. A large hard drive gives you the option to expand in the future, and you can never go wrong with a notebook computer that can give you fast access to your stored data.

It is even more crucial that you go with the top-of-the-line hard drive size and RPM for your notebook computer if you are fond of computer games, you have a lot of multimedia files, or you want to be able to easily upgrade your programs. These games, content and programs take up a lot of space. A high RPM hard drive can also cut down on game load times, giving you more time enjoying your games and less time staring at loading screens.

Windows Vista Home settings

Hard Disk

This category contains the Turn Off Hard Disk After setting. The hard disk is one of the most power-hungry components of a computer, so turning off the hard disk saves a worthwhile amount of energy. After the hard disk has spun down, it will take a few seconds to spin back up when you start using the computer again.

Wireless Adapter Settings

This category contains the Power Saving Mode setting for your computer s wireless adapter. You can choose Maximum Performance, Low Power Saving, Medium Power Saving, or Maximum Power Saving. Many laptop computers allow you to switch off the wireless adapter altogether via either a hardware switch or a custom keyboard combination.

Sleep

This category contains three settings:

Sleep After Specify the number of minutes to wait before putting the computer to sleep. Normally, you d set this setting by using the Put the Computer to Sleep drop-down list in the Edit Plan Settings window.

Allow Hybrid Sleep Choose On or Off to control whether Windows uses hybrid sleep, a mode that saves power while enabling you to resume your work almost immediately.

Hibernate After Specify the number of minutes of inactivity that Windows should allow before it puts the computer into hibernation. Choose Never if you want to prevent hibernation.

Power Buttons and Lid

This category contains the following settings:

Lid Close Action For a laptop, choose the action that Windows should take when you close the lid: Do Nothing, Sleep, Hibernate, or Shut Down. Normally, you d set this setting in the System Settings window.

Power Button Action Choose the action that Windows should take when you press the power button: Do Nothing, Sleep, Hibernate, or Shut Down. Normally, you d set this setting in the System Settings window.

Sleep Button Action Choose the action that Windows should take when you press the Sleep button: Do Nothing, Sleep, or Hibernate. Normally, you d set this setting in the System Settings window.

Start Menu Power Button Choose the action that Windows should take when you click the Power button on the Start menu: Do Nothing, Sleep, or Hibernate.

PCI Express

This category contains the Link State Power Management setting, which lets you choose the Active State Power Management policy to use: Off, Moderate Power Savings, or Maximum Power Savings.

Search and Indexing

This category contains the Power Savings Mode setting, which lets you choose which power plan to use for search and indexing: Power Saver, Balanced, or High Performance.

Display

This category contains the following options:

Turn Display Off After Specify how many minutes of inactivity Windows should allow before it turns off the display. Normally, you ll choose this setting in the Edit Plan Settings window.

Adaptive Display Choose On or Off to specify whether Windows should increase the Turn Display Off After setting automatically if you keep turning it back on when it goes off. This setting is often helpful for getting the right display-off delay on laptops.

Display Brightness For a laptop, choose the brightness to use when running on battery and when plugged in. Normally, you ll choose this setting in the Edit Plan Settings window.

Multimedia Settings

This category contains the When Sharing Media setting, which lets you specify what Windows should do if your computer is sharing media for example, songs with other computers. If your computer goes to sleep, the other computers will no longer be able to access the media. Choose Allow the Computer to Sleep, Prevent Idling to Sleep, or Allow the Computer to Enter Away Mode, as needed. Away mode is a kind of somnolence in which the computer appears to be asleep but can still take actions such as recording TV shows or sharing media with other computers.

Battery

This category contains settings for managing low and critical battery levels, alarms, and actions. Article 14 discusses these settings in more detail as batteries are mostly used in portable computers.

The Bottom Line Find out what hardware you can use with Windows Windows works with a wide variety of hardware provided that you can find a suitable driver for each device. You can use the Windows Vista Upgrade Adviser page on the Microsoft website to find out whether a particular device is compatible with Windows Vista.

Install, connect, and disconnect hot-pluggable devices Hot-pluggable devices are ones that you can plug in or unplug while Windows is running. Hot-pluggable devices use USB, FireWire, and PC Card connections. Windows automatically loads and unloads drivers for hot-pluggable devices as needed. You must be an Administrator or provide an Administrator password to install a hot-pluggable device. After that, any user can plug in or unplug a hot-pluggable device.

Install devices that are not hot pluggable To install a device that isn t hot pluggable, turn off your computer and disconnect the power. Open the case, install and secure the device, and then close the case again. When you restart your computer after installing the device, Windows normally detects the device during startup. If Windows can find a driver for the device, it loads the driver automatically and configures the device. If Windows can t find a driver, it launches the Found New Hardware Wizard, which lets you tell Windows where to find the driver. If Windows doesn t detect the device, you can run the Add Hardware Wizard to install the device manually.

Update, roll back, disable, and uninstall drivers To work with drivers, press Windows Key+Break,click the Device Manager link in the System window, and then authenticate your- self to User Account Control. Right-click the device whose driver you want to change, and then choose Properties from the context menu. Use the buttons on the Driver page of the device s Properties dialog box to update, roll back, disable, or uninstall a driver.

Configure power management to improve battery life or reduce consumption To improve battery life on a laptop computer or to reduce power consumption on a desktop, you can configure power options such as turning off the display or putting the computer to sleep after a specified period of inactivity. To work with these options, choose Start Control Panel, click the Hardware and Sound link, and then click the Power Options link. In the Power Options window, choose a power plan, and then click the Change Plan Settings link to customize its settings. Use the links in the left column of the Power Options window to access the main power configuration options.

Advanced Notebook Research - Neutron MMO Review

Why are some notebook computers so expensive? Like most other things in life, it seems that you pay a lot for the name. Proving that portable power needn't cost a fortune, this notebook from ANR (no, I hadn't heard of them either) has all the features of similar machines from the likes of Dell, Compaq and Toshiba, with one exception; it costs far less. For a thousand pounds or so, you wouldn't really expect a great deal from a notebook. Either it should be slow, or appallingly badly made, or quite possibly both. But this is neither. The Neutron bears a striking resemblance to one of Dell's notebook products from last year. It's solid and well-made, comes with a floppy drive and 24-speed CDROM drive, and is powered by a long-lasting Lithium-Ion battery (with LEDs on it to show how charged it is).

At the heart of this notebook is a Pentium MMO processor, running at either 233MHz or, in the case of our review machine, 266MHz. There's 32MB of system memory, and although the 2GB hard drive isn't as spacious as those in some other machines, it should suffice for most business users. Despite being a fairly large notebook PC, there isn't room for both the CDROM drive and the floppy drive to be installed at the same time. Both are supplied, however, and you can use either of them by plugging one into the expansion port. If you want to use both at the same time, you can do that too, but you have to plug the floppy drive in externally using the supplied cable.

The Neutron has a good comfortable keyboard, a large wrist-rest and a glidepad mouse with two buttons. Input/output features include an infra-red port, a USB port, the usual serial, parallel and monitor connectors plus a PS/2 mouse/keyboard port. There are also two PC Card (PCMCIA) Type II slots, while sound is generated by a Crystal FM chip. The 12.1-inch LCD display is very bright, so using it outdoors or in a brightly-lit office won't be a problem. The maximum resolution available on this screen is 800 x 600, with 16.7 million colours generated by the NeoMagic graphics adapter. The Neutron comes with Windows 95 pre-installed on the hard drive, along with a copy of Lotus SmartSuite 97. It even comes with a carry case.

Advanced Notebook Research - Neutron MMO features - Verdict

This machine is something of a revelation. It's fast, well-made and costs far less than most of its competitors. It is unlikely to generate quite as much admiration on the train as one of the more stylish machines from the better-known vendors, but that doesn't matter; it's hard to fault the Neutron's value for money.

Advanced Notebook Research - Neutron MMO price

999 + VAT (233MHz) or 1,049 + VAT (266MHz)

Stak Trading: 01788 577 497

Google AdSense Overview

Google AdSense Overview

Google AdSense is the program that can give you advertising revenue from each page on your website with a minimal investment in time and no additional resources.

AdSense delivers relevant text and image ads that are precisely targeted to your site and your site content. And when you add a Google search box to your site, AdSense delivers relevant text ads that are targeted to the Google search results pages generated by your visitors search request.

Earn more revenue

You can maximize your revenue potential by displaying Google ads on your website. Google puts relevant CPC (cost-per-click) and CPM (cost per thousand impressions) ads through the same auction, and lets them compete against one another. The auction takes place instantaneously, and, when it s over, AdSense automatically displays the text or image ad(s) that will generate the maximum revenue for a page -- and the maximum revenue for you.

Get started in minutes

Becoming an AdSense publisher is simple. All it takes is a single online application. Once you're approved, AdSense takes only minutes to set-up. Just copy and paste a block of HTML and targeted ads start showing up on your website.

Access thousands of advertisers

With Google's extensive advertiser base, we have ads for all categories of businesses-and for practically all types of content, no matter how broad or specialized. And since Google provides the ads, you have no advertiser relationships to maintain.

The AdSense program represents advertisers ranging from large global brands to small and local companies. Ads are also targeted by geography, so global businesses can display local advertising with no additional effort. And you can use AdSense in many languages.

Google grasps the meaning of your content

AdSense can deliver relevant ads because Google understands the meaning of a web page. We've refined our technology, and it keeps getting smarter all the time. For example, words can have several different meanings, depending on context. Google technology grasps these distinctions, so you get more targeted ads.

Make extra money with a Google search box

Place a Google search box on your site, and you can start monetizing the results from web searches. Not only does this keep your users on your website longer since they can search from where they are it takes just minutes to implement. And you pay nothing to participate.

Show only appropriate ads

Google's ad review process ensures that the ads you serve are not only family-friendly, but also comply with our strict editorial guidelines. We combine sensitive language filters, your input, and a team of linguists with good hard common sense to automatically filter out ads that may be inappropriate for your content. What's more, you can block competitive ads and choose your own default ads. It's your show from start to finish.

Competitive Filter
Enables you to filter out specific competitors or specific advertisers

Contextual Filter
Eliminate delivery of ads that would be inappropriate to serve on pages

Editorial Review
All Google ads are reviewed and approved before being served on your pages

Customizable default ads
In the unlikely event that Google is unable to serve targeted ads on your page, we provide the option to display a default ad of your choice

Customize AdSense for your site

You can customize the appearance of ads, choosing from a wide range of colors and templates. Ditto with your search results page. Your reports are customizable, too. Flexible reporting tools let you group your pages in any way you want so you can view your results by URL, domain, ad type, category and more to learn where your earnings are coming from.

See what our customers say

Instead of spending money to hire an additional sales rep to sell ad banners, Google ads have become a virtual sales tool for us. Now we re able to reap thousands of dollars in additional advertising revenue each month that we would very likely have missed without Google AdSense.
- Robert Hoskins, Editor and Group Publisher, Broadband Wireless Exchange

Google shows targeted ads reflecting the sorts of information and services SeatGuru visitors want. For a small business like mine, this is the best approach to advertising. You set it up easily, it automatically serves relevant ads, and it takes very little of my time.
- Matt Daimler, Founder, SeatGuru.com

At the beginning I was very concerned that I might lose traffic to competitors. I only used AdSense on a limited number of the site s pages, and I watched the stats very carefully. If the traffic, pages per visitor, or conversion rates dropped I knew I could easily pull the ads...Since implementing AdSense, our ad revenue has increased more than tenfold, and 100 percent of my available inventory is now sold through AdSense.
- Vik Kachoria, Entrepreneur, Real Adventure.

You can run Google ads on all or just some of your pages, using AdSense strategically to complement your direct sales team. You'll pay nothing, spend little time on set-up, and have no maintenance worries. You can use AdSense for a day, a month or for however long it pleases you to make a profit-it's your choice.

Report: ATandT, Apple in iPhone Contract Talks

How much longer can AT&T hang on to its exclusive contract with Apple's white-hot iPhone? A report from The Wall Street Journal says company CEO Randall Stephenson is pushing for exclusivity rights through 2011.

Sources quoted by The Wall Street Journal (WSJ) say telecommunications giant AT&T s CEO, Randall Stephenson, is pushing to extend the company s exclusive contract with Apple for the popular iPhone, which people familiar with the matter say expires this year. The WSJ reported that Stephenson is looking to extend the relationship through 2011.

Apple refused to comment on the report, noting only that they have a great relationship with AT&T, which has experienced a revitalization of its brand since it started carrying the iPhone in 2007. The continued, and expanding, popularity of Apple s touchscreen smartphone, which has become an iconic device, suggests AT&T would be wise to fight hard to keep its exclusive deal with the iPhone. AT&T has benefited tremendously from the contract picking up 4.3 million iPhone subscribers in the second half of last year, of which 40 percent were newly acquired customers.

Apple and AT&T have negotiated contract extensions before, in fact. In August 2008, the two companies agreed to extend their relationship through 2009 after AT&T came to Apple with a $300-per-iPhone subsidy in lieu of a revenue-sharing model. While Stephenson admitted the move would dilute earnings through 2009, the company could now offer the feature-packed iPhone 3G for $199 with a two-year contract.

Stephenson told the WSJ that the deal was indeed a multi-year contract but declined to elaborate, and said substantial investment in wireless technology would be made regardless of the company s involvement with Apple. "This business cycle is going to cycle," Mr. Stephenson told the WSJ. "You got to make sure that you're positioned when it cycles back out to be the leader in the industry, and to do that you have to be the leader in mobility, first and foremost."

This March, AT&T announced it would offer iPhones without the two-year plan for $599 or $699, although those phones are locked to AT&T s network. Apple quickly followed suit in its own retail stores. All told, Apple has sold more than 17 million iPhones in less than two years. In August 2008, Gene Munster, an analyst with investment firm Piper Jaffray, boldly predicted Apple would sell 45 million iPhones in 2009. More conservative estimates put the figure closer to 25 million.

Rumors are swirling yet again as to what features Apple will include in the upcoming upgrade, unofficially dubbed the iPhone 3.0 or iPhone 4G . Various reports suggest the latest iPhone will offer video editing software, a built-in FM radio and support for 802.11n Wi-Fi networking. A report by Lazard Capital Markets semiconductors analyst Daniel Amir, suggests production of two versions of iPhones will be introduced this year, debuting in June.

Plug Computers: Computers in the Socket

The idea of computers in the electrical socket takes you to the world of imagination and sci-fi movies. But Marvell Technology Group Ltd., is soon going to launch on a computing device like this named plug computers.

Marvell Technology Group Ltd., a company that makes chips for a range of high tech products, communications equipment, cellphones, etc, has planned to launch a new kind of computer. The company has named it Plug Computers . Like its name this device would be plugged in to home electrical sockets and would be of socket like size. Yet it will have enough power to manage user's digital media and enable them to view it over the Internet from outside the home.

In today's digital world we store each and every information in the digital form as texts, images, videos in digital cameras, cellphones, notebooks. In such a way we are storing our personal information in dispersed style in the form of files, that make them inefficient as well as risky. Losing a laptop or mobile phone will cost us losing a precious photo or video.

Marvell is promoting the "plug computers" as a perfect solution for this. The idea is to have an ultra-small computer plugged into an electrical socket. Despite the small size the plug computer will have enough processing power and network connectivity to manage and serve media stored on an attached thumb-drive or hard drive. You can access the plug computer over your home network, enabling you to get at your files from wherever you needed in your house.

However this idea is not new and Apple's Time Capsule works a little like that. It acts like a central repository for data by wirelessly backing up all the connected Macs. HP's MediaSmart Servers are a host of "smart" external hard drives connecting a PC via USB and store your media longterm, and serve it to connected TVs and audio systems without needing the PC's intervention.

Marvel is planning to miniaturize all this technology and make it small and convenient. The company is also emphasizing on the green aspects as well by maintaining the eco friendliness of the plan. Plug computers are supposed to draw less than 5W of power that is much less compared to a PC running as a media server.

Company is planning to launch it on a small and economic-enough scale. Marvell will be sourcing the chips while partner companies make the software & hardware. The price is interesting targeted at $50 that makes this idea different from other tech solutions.

My First Laptop

It is really astonishing to look at the progress laptops have made in just a few years. Last quarter, laptop sales

overtook desktop sales for the first time in history. These days the pricing of low end PCs, both laptop and desktops are similar and so it has become worth wondering whether to buy a desktop at all. In a few months I will purchase my first notebook computer and being fifteen, I am not able to buy a 17 inch widescreen Dell XPS or the Savrow line of laptops. Instead I look through the budget, the low price, and the beginner laptops for one that will catch my eye.

These days the features and specifications of cheap laptops surprise me several laptops around the 500 mark include DVD burners and integrated WiFi receivers, which at the beginning of the year were only in the 1200+ laptops that would not be within the reach of the first time buyer. Of course there are some such as the Lenovo IBM ThinkPad R50e which does retail for 505 and only have 256MB of RAM and no DVD burner and no integrated WiFi. I should not be disappointed. One year ago, those would be acceptable specifications for a mid range laptop and today they are unacceptable for a bargain computer such as the Dell Inspiron 2200. How things have changed.

Recently Apple upgraded their iBook range, which starts at 700, and the laptops now include Bluetooth and WiFi as well as 512MB RAM and a 40GB hard drive. The 12inch iBook is pricey, at 200 more than two of its Windows competitors, the Acer 3502WLMi and the Dell Inspiron 2200. Both the Acer and the Dell have slightly faster processors, DVD burners (which Apple calls the SuperDrive) and the world s favourite operating system. I love Apple computers, but I cannot buy an iBook and feel that I have made the best decision. Even the expensive PowerBook lines are bad value when compared with the Sony Vaios, IBM ThinkPads and Dell Precision lines.

The reason that the Windows laptops are better is the processor, the number of features and the fact that Apple s care and attention to detail is not worth 200 to a person like me. I appreciate their efforts but when they lose out on the first time buyers, they may set a trend. The buyer brings home their brand new Windows laptop and all the feelings of euphoria are now attached to a Windows laptop, and not the iBook. Apple cannot afford to continue doing this and hopefully the Intel switch will bring down prices or save money, letting them add features such as the SuperDrive.

Dell makes laptops in every segment of the market. Their high end laptops are well made and have some quirky touches like the lights on the XPS. Of course when a company sets out to make budget laptops, cost cutting is an integral part of the mix. Dell immediately threw out build quality and attention to detail. They added the DVD burner and the WiFi which I appreciate but if my laptop creaks as I open it, as a year-old Inspiron 1000 does, I will feel quite disappointed. The Dell does only have a 40GB hard drive which is adequate for now but 60 or 80GB is better.

IBM does put the effort in to make quality laptops. This means their ThinkPad R50e does not have the same features, no DVD burner and no WiFi but the excellent keyboard and the pointing device, are better than Dell s cut-price keyboard and the slippery trackpad. I am a person who values the extra features, the DVD burner is very important and Acer s Aspire 3502WLMi has a dual-layer burner which means almost 10GB of data on one disk. Since I don t want to skimp on the quality so I cannot see myself buying the poorly made but inexpensive Dell Inspiron 2200.

Asus is a relatively unknown computer company who, like IBM , value quality but unlike IBM don t price it highly. Their laptops are made out of metal and have a small form factor while maintaining a long list of features. However, they only have 256MB RAM in the A3L-5001H which is a beautiful machine, more attractive than any other Windows laptop in this price range. It has Windows XP Professional which is far superior to Windows XP Home Edition, a comparison on Microsoft s website shows how significant the gap is between the two versions. However, there is no DVD burner. WiFi is included. The best thing is that Asus offers 1GB of RAM for only 90. This upgrade usually costs around 250- 400 in most laptops. A Celeron M 370 and a 60GB hard drive are just icing on the cake.

The lack of a DVD burner is offset by Windows XP Professional and the fantastic amount of RAM does mean the price is higher than I would normally pay. 640 is tantalisingly close to an iBook, but the iBook has 20GB less space and 512MB less RAM. RAM is so important that spending a little more on it is worth every penny. So all the big names are beaten by an unknown manufacturer. Seems like a bad decision but knowing that my machine looks and feels expensive while having 1GB of RAM and Windows XP Professional are more than enough to make up for it.

The other option is Acer s Aspire 3002LMi, with 512MB RAM, 60GB, Windows XP Home Edition and a dual layer DVD burner, WiFi but an AMD processor. Acer s Aspire 3502WLMi has 20GB less, an Intel Celeron M 360 and costs the same. The Aspire 3002LMi can be bought for 501 which is unbelievably cheap. When compared with the Asus, the upsides are 210, a DVD burner and a widescreen display. The downsides are Windows XP Home Edition, half the RAM and the aforementioned build quality.

Of course if you are in the market to buy a new laptop and need one now, then consider these options. Otherwise, wait for Windows Vista (or Mac OS X 10.5 Leopard) in 2006 and laptops with more RAM, larger hard drives, bigger screens and DVD burners and WiFi as standard.

Apples Keynote 08 Delivers Simple Sophistication

Review: Apple is stressing Keynote's ease of use, billing the application as a means for anyone to create "cinema-quality presentations."

The debut of Apples iWork 08 includes across-the-board improvements, such as new templates and text effects, and a few snazzy bells and whistles to its presentation program, Keynote.

As with the rest of the iWork 08 suite, Apple is stressing Keynotes ease of use, billing the application as a means for anyone to create "cinema-quality presentations."

eWEEK Labs tested out a number of the applications souped up features, such as Keynotes newly unveiled Smart Builds tool, which enables users to create animations with a minimum of hassle. I was impressed with the Smart Builds tool, and found that it makes good its promises of sophistication without excessive complication, but the feature took a bit of practice to nail down.

Another significant new feature of Keynote is the programs point A to point B animation, which enables users to move object, image, shape, chart, and the like from one location on a slide to another.

For all the presentation-building magic that Apple has managed to pack into Keynote 08, the trick that this application doesnt pull off seamlessly is compatibility with Microsofts Office file formats. Keynote will open and export to Offices Powerpoint file formats, but as with every non-Microsoft consumer of Offices formats that eWEEK Labs has tested certain formatting inconsistencies seem impossible to avoid.

iWork 08 is reasonably priced, at $79 (or free with the purchase of any new Mac computer). The suite requires Mac OS X version 10.4.10 or later.

Keynote Presentation

The first thing I worked through during my testing of Keynote 08 was the heavily hyped Smart Builds feature that enables users to include animated elements in presentations. According to Apples Web site, all I needed to do to achieve instant animation would be to simply drop a photograph or any other image of my choosing into the appropriate spot in my presentation.

I opened up the Smart Builds feature by clicking on its icon located in Keynotes toolbar which brought forth a separate pane for working with and customizing animated elements, along with a second pane, called a photo window, that appeared at the bottom of the screen. I could drag photos or images into the photo window from Apples iPhoto Library, or from OS Xs Finder file manager.

I dragged a series of test images from iPhoto folder into a series of rectangles that appeared in the photo window at the bottom of my screen. As I dragged an image into one of the rectangles, another, blank rectangle automatically appeared. I dragged in four images to fill out a spinning cube animation, which Id selected from a drop-down menu within the Smart Builds action pane. From there, I was able to further modify the animated object by specifying its direction, alignment, and perspective.

The action pane also let me further define whether I wanted the cube to move from left to right, or how many times I wanted the cube to spin before it settled on displaying one of the four images it was built to showcase. I could set different timings for each photo by opening the aptly-named Build Order drawer from the Smart Build pane. I could also select whether I wanted the images Id selected to be scaled to a common size by selecting a box located inside the photo window.

To remove an image from the build, all I had to do was grab it and drag it out of the photo window, or right-click the image and select delete. To rearrange the order in which I wanted the images appear, I simply dragged the image to place within the rectangle sequence where I wanted it to appear. The entire process ran rather smoothly, and it was actually pretty fun to do. Whats more, the resulting slide was significantly snazzier than my non-animated slides.

I also tested Keynote 08s groovy A-to-B animation feature. I highlighted an image on my test presentation that I wished to move across the slide, opened Keynotes Build Inspector tool, and clicked the action button. From here I was able to choose the "move" option listed under the Effect menu. Once I did, the image appeared on my presentation slide with a red line that connected my original image, or Point A, to its next destination, Point B. Point B was designated by a "ghosted" image of my original image. I could also add a series of other destinations.

When I viewed my slide with this added effect, the result was great. I could choose to have my image move from point-to-point on either a straight or curved path when I clicked the Path option located on the action pane. Even better, I was able to shape the path of my image any way I chose by grabbing one of the nodes used to illustrate the images destined path. I could make the path as curvy and unique as I wanted.

Finally, I tested Keynotes file conversion fidelity and imported a PowerPoint file into the application. Overall, the conversion fidelity was good, but I did run into a few subtle alignment issues (some text was pushed into the files footer), the biggest errors dealt with the translation of symbols used in the Microsoft file into Keynote. Arrows that appeared in the original PowerPoint file became in Keynote and bullets that appeared in the PowerPoint file became boxes in Keynote.

Dual-Core Processor Wars: AMD X2 vs Intel Pentium D

There s a war going on and the latest battle continues to offer promise and good prices to consumers looking for the best stuff for their computer.

Since the inception of dual-core processors a little while back the race has been on to see who can get the better chip with this dual-core processor technology.

During the final days of the single-core battles, there was a stalemate between AMD and Intel. Intel s clocked higher but were unable to match the speeds that the AMD managed at lower clock speeds.

The oldest difference between them has been their suitability for specific tasks. AMD have had the gaming sector in the bag, especially in terms of the value for money possible with their lower clocked chips, which could be overclocked to the same speeds as their top models. Intel has the crown for general performance. When it comes to office related tasks, Intel processors are able to outperform AMD chips in these areas.

As the ability to clock the chips any higher became more and more difficult technically, the next step was to just add another core, theoretically allowing twice as much number crunching in a dual-core processor. This is not exactly how it works however.

Modern operating systems and programs have not been designed with multiple-core or dual-core processors in mind. They were designed to make use of one core on one processor. The major expense that went with multiple processor computers was the circuitry needed to split tasks up amongst the processors and sharing cache.

Dual-core processors simply act like two places for tasks to go. Instead of single tasks getting split up and performed in two different places, as is the case with traditional single core processors, single threads get split up amongst the cores. This essentially means that each program gets assigned to a core.

Because of this there is absolutely no increase in speed for gaming from dual-core processor chips. Only once the games themselves have been programmed to take advantage of dual-core processors will there be a difference. This is due to the intensive nature of games and the number crunching needed for intense graphics, which for now cannot be split over multiple cores in dual-core processors.

So back to the battlefield.

AMD were the first to introduce their dual-core processor solution to a desktop computer. This gave them a slight lead over Intel. Despite this, AMD gave people a bit of a surprise with their new offering.

Always having been renowned for giving far more than expected for the price, these new dual-core processors were very expensive. Part of what managed to give AMD a hold in a market previously dominated by Intel was their good pricing. This shock did not go down well with consumers.

To add insult to injury, Intel s dual-core processor offerings came in at remarkably good value. Both of their initial dual-core processors cost less than AMD s lowest priced model. That s right, AMD s cheapest dual-core processor cost more than Intel s most expensive. This definitely put the ball in Intel s court and was downright disappointing for AMD fans.

AMD did manage to introduce a cheaper model to compete better with the Intel offerings. Despite this, Intel was still the forerunner in this area.

Performance remains an area that is sketchy.

With the relatively new technology involved it is hard to draw a clear conclusion on who is faster. With operating systems only recently oriented towards fully utilizing dual-core processor technology, it is still new territory. Both offer increased performance, but as to who will rule the roost, we ll have to see.

For the meantime it would probably be advisable to just watch. Being a cautious buyer I prefer to buy into a sure thing, once things have settled down, prices will balance out and all the related technology will be in place. Then we will be able to get a true opinion on where to put your hard earned cash.

Buying a Used Laptop Computer

Buying a used or refurbished laptop is much the same as buying a new one except you are going to get a much better buy! When considering buying a used laptop, the first thing to do is to determine what your needs are.

What do you want to use the laptop for? *Word Processing *Internet Browsing *Use at Work and at Home *On-line Shopping *Database Applications *Personal Finance and Online Banking The reason for assessing what you applications you need are that most refurbished laptops often only include the Operating System (OS). Some don t even have an OS installed so make sure you know what you re buying before you spend your money.

Once you establish your computing needs, you need to determine your budget. Refurbished laptops don t always come with an operational battery. If you need a battery, shop around to figure the cost to replace one. You should know that older laptop batteries don t last more than an hour or two, and even purchasing a new battery for the purpose of longer battery life may not be worth the expense. You should also stick with name brand battery manufacturers like IBM, Dell, Toshiba and Compaq-HP.

Once you have your refurbished laptop, you may not know what to do next. If you are new to computers and you want to browse the World Wide Web, you will need to obtain the services of an ISP (Internet Service Provider). There are basically two types of Internet access options: broadband (cable modem, DSL, satellite) and dial up. Broadband is the preferred type since download speeds can range from 128kbs to 6000kbs (faster is better). But, if your budget is tight, dial-up access will work fine for typical browsing and e-mail usage.

If you bought your used laptop for gaming, you definitely need a reliable broadband connection. Gaming over a dial up connection will be frustrating and on some cases even impossible. That is why it s critical that you check out the minimum systems requirement for the games you like before buying the laptop. You want to make sure the CPU speed and the RAM and graphic chip requirements will support your needs.

Finally, where do you buy your used or refurbished laptops? * Some people choose to search at www.ebay.com. If you be sure to check out the seller to be sure you will have a smooth transaction.

* Many don t want the hassle of bidding, so will use their favorite search engine:

How do you choose once you have a list? 1. Look for online reviews 2. Make sure they have a BBB Online Insignia 3. Make sure their service is up to you standard. Most of the vendors have 800 numbers, so it won t cost anything to call.

4. What do their prices look like? If all the above seems like too much of a hassle, then buy a new computer. It will cost around $800 + but will come with a new battery and a one year warranty (although some new ones seem to have only 90 day warranties). It will also have the latest Windows XP system and an 800 number to call the vendor, should there be a problem.

How To Remanufacture 1600/2600n Color Laser Printer Toner?

This is one of the first color laser printer toner

where HP/Canon really seems to have gone out of its way to make a toner cartridge very difficult to remanufacture. The waste chamber, which consists of the waste chamber, OPC drum, PCR, wiper and recovery blades, is plastic welded/glued together. The drum axle/bushings are permanently attached to the waste chamber. The only way to get them off is to physically break or cut the cartridge apart. New replacement waste chambers are now available that include the waste chamber, new removable drum axles/bushings, foam seals, electrical contacts and PCR holders. The kit will also contain the screws, springs and plastic pins that will be needed to reassemble the cartridge. If you want to reuse any of the above parts, you will have to cut the OEM chamber apart. The waste chamber for 2600n color laser printer toner is also very small. The aftermarket toner will have to be very efficient to prevent leakage due to the waste overflowing. When you refill 2600n hp color laserjet toner, you should notice following factors to guarantee the quality:

1) Mitsubishi toner is one of the best choice to remanufacture hp 2600n hp color laserjet toner, physical toner powder is more suitable for refilling color laser printer toner cartridge.

2) High quality toner cartridge smartchip can guarantee the page yield of the color laserjet toner.

3) New Hanp opc drum is value to consider, because the opc drum is easily worn out.

How to find cheap laptop computers.

Ah yes, I want a laptop but I am not going to spend a couple of thousand dollars for one. Well guess what you don t have to. Laptop prices have come down dramatically over the past year alone and they will continue to do so as technology advances. But the trick here is to find good quality laptops that fit your needs at the cheapest prices available today.

I would say that there probably is a store near you right now that has cheap laptop computers. In fact, many stores already have them. The reason being, like any other new product, laptops were once considered the cream of the crop in the computer world which made them very expensive. However, all that has changed now. Laptops are a dime a dozen! The hand held digital assistants, Bluetooth cell phones and tablet pads are the new rage making laptop computers cheap.

Now, don t get me wrong, this does not mean that they are cheaply made. Thanks to the wonders of the technological cycle, laptop computers are decreasing in price as their capabilities rise. Of course, there are the latest and greatest monsters out there that are made for gaming or high powered multimedia applications and these babies still cost a pretty penny.

But for the average user, you can find cheap laptop computers that provide all the power you need and then some. Every major manufacturer out there, like Dell, HP, Compaq, Gateway, and IBM have their lower end and intermediate models that come with more than enough speed and usability.

Now here is the key to finding the right cheap computer laptop for you, and that is to figure out exactly what you need it for.

Are you going to use it mainly for surfing the web or word processing? Do you need it to work from home or mainly to save your MP3s and digital pictures?

Ok, so now you have an idea of what you want to use your laptop for. Now lets go out shopping and compare. You can visit any of the top manufacturers websites or visit your local store and find their low end or intermediate models that may suit your needs. The three top components of a computer you want to look for is the hard drive size, memory, and processor speeds and take notes of each model you find on each component and model.

The hard drive, you can consider this the brain of your computer, this is where all your files, applications and folders are stored. If you plan on using your computer for MP3s and digital pictures your hard drive should be large since these files are usually very large. I personally would look at 80gb as minimum.

Next would be the memory, memory can be considered the thought processes of your computer. As a minimum I would look at 512mb but if you plan on using your laptop for gaming of course this should be much larger, in the area of 1 to 2gb. Now memory is used whenever a program or application is running. So the more memory you have the faster your computer can process the program.

And finally your processor, now your processor is just that it processes all the inner workings of how each program runs. The faster the processor is, the faster the program instructions are processed. Again if your looking for a laptop for gaming uses you want your processor with high speeds 2ghz or more. For other uses you can go less.

Other parts of the computer to also consider are the ports involved that can connect your computer to your digital camera or your mp3 player for example. You also want to check that your laptop has wireless and broadband connectivity. Many cheap computer laptops today already come with this but you want to make sure or you will have to pay additional, for example, a wireless card to install in your laptop to have this capability.

Is Steve Jobs Behind Apple's Rumored Netbook Development?

Apple iPhone and the Enterprise: Happy Together?

The Apple iPhone can find a comfortable home in the enterprise, a new report from Forrester Research suggests. The RIM BlackBerry is still a superior messaging and calendar device, eWEEK is told, but with the iPhone 3.0 addressing many often-voiced security concerns, for content-centric applications, the iPhone is becoming the sanctioned enterprise device of choice.

Few disagree that, with the iPhone, Apple changed users expectations of devices and how they interact with them in short, mobility. Whether the iPhone is a fit for the enterprise, however, is a topic that provokes debate.

Forrester Research released a report on April 10, Making iPhone Work in the Enterprise: Early Lessons Learned, in which report author Ted Schadler offers the experiences of three enterprises Kraft Foods, Oracle and a California-based pharmaceuticals company that have adopted iPhones.

Each example offers the pros and cons of the experience, but the report which points out challenges to avoid, as well as advice for properly planning cultural, support and provisioning changes is in favor of iPhone adoption within enterprises.

Ultimately, Schadler suggests that the security concerns that prevented adoption are no longer valid for some companies, particularly with the iPhone 3.0 addressing many of the remaining concerns, such as forcing a user to sign into the VPN each time, instead of automatically signing her in.

The IT staff at Kraft Foods saw iPhone adoption as a way of proving to its work force that it was serious about introducing new tools and technologies in support of them, and in April 2008 it became a part of Apple s iPhone Enterprise Beta program.

Every time Apple puts out a new release on the consumer side, they re very private about it, explained Schadler. On the software side they ve been much more open. The way companies work is, they want to know what s going on and want to be part of a vetting program.

The Enterprise Beta program, Schadler said, is a way of addressing this.

Enterprises want to see themselves as partners, they want to be involved, Schadler added. IBM, Microsoft and Oracle, for example, have become much more open about sharing the next version and what it s going to happen.

Apple, he said, began to do this with the iPhone 2.0.

As of this past January, almost half of Kraft Foods mobile team were using iPhones a number Schadler pointed out is significant, given that mobile adoption at that stage is generally 10 percent, with 20 percent being the higher end and about 400 new iPhones are being ordered each month.

Among the benefits Kraft is seeing is a change in the culture of the company to take advantage of new technologies; among the challenges were problems with calendar synchronization.

PC to TV Conversion - Put Your Desktop On a TV

With the recent popularity of Video on Demand networks that allow internet users to download television programming and movies to their hard drive the idea of watching this programming on a regular TV is tempting. Sometimes a 17" monitor just doesn t do it - in fact, if you have several people crowding around the monitor even a 30" Cinema Display might not do the job.

PC to TV Converters

Now, regardless of the availability of an analog output on your PC (which most computers don t have) you can still project your desktop onto a television set. This requires a little understanding about what hardware you are working with on both ends. Let s start with the PC.

Most PC s have either a VGA or DVI output. This can get confusing - VGA is analog and DVI can either be analog or digital (although it is increasingly more common these days for DVI to be used in a digital environment).

Now look at the input available on your television set. If you have a HDTV you probably have some form of digital input. If you don t have a high-definition TV you will probably want to find component inputs (aka RCA). These are the red, white and yellow inputs available on most television sets. Another alternative is S-Video.

VGA out to Component

This is the most popular type of PC to TV Converter. Simply plug it into your VGA output on your video card (or motherboard) and plug the other end into your TV - the image should show up within a minute. Higher quality adapters do a much better job of converting the image for TV and make a big difference. This is especially important for screens larger than 30 inches. A very similar adapter that supports HDTV is a better option for screens larger than 30 inches.

VGA out to DVI

Most DVI television sets support digital input only (though some older ones do support an analog signal). In this case you have two options - adding a digital video card or using a VGA to DVI conversion box.

A VGA to DVI conversion box is typically more expensive because it actually takes the analog signal and converts it to a pure digital signal. As a result the quality is usually very good with these adapters. Add-in cards (with DVI) produce pure digital signals, also, but the resolution depends on the quality of the card. Most DVI video cards support high-definition resolutions (and much higher), so they work well in these scenarios.

DVI out to Component

Some DVI video cards actually support video-out through the DVI port (an analog signal). If you have such a video card then a DVI to component cable should do the trick. Be careful with this one, however, since many DVI video cards only support an analog signal.

Wireless PC to TV

If you are trying to find a Wireless PC to TV Converter they are now available. This works with any television set with a component-in option and a VGA out on the PC. These run on the 2.4 GHz band, so they may interfere with some common home devices though this is rare since they hunt for open channels.

The technology to adapt your PC experience to the living room is getting better everyday. Whether you are looking to stream video to your TV from your PC or you just want to do some email on the big-screen you now have plenty of options.

Apple Leads and Dell Lags on Customer Experience

Forrester reports Apple rated highest on customer surveys ranking the usefulness, usability and enjoyableness of their interactions with PC makers Apple, Compaq, Dell, Gateway and HP. All showed room for improvement, however, as the PC industry as a whole received a poor rating, ranking below banks, credit card providers and even airlines.

Apple leads and Dell lags, was the summary of an April 17 Customer Experience Index (CxPi) 2008 Snapshot from Forrester Research.

The Snapshot took a took a closer look at how five PC makers Apple, Compaq, Dell, Gateway and Hewlett-Packard fared within its CxPi, which polled 4,600 consumers about their interactions with various companies across 12 industries, gauging usefulness, usability and how pleasant the interactions were.

Forrester s overall verdict for the PC makers? Poor.

While customer experience is important for PC makers to cultivate loyal customers, they aren t doing a very good job, wrote Forrester analyst Bruce D. Temkin.

As a group, these firms received a poor rating for their customer experience, coming in ahead of only ISPs, TV service providers and health plans.

On individual ratings, Apple scored a Good rating of 80 percent. Under the Okay category, Gateway was next in line, with 66 percent, following by HP with 64 percent and Compaq with 63 percent. Dell, with a 58 percent rating, fell under the Poor category.

Across all three areas studied by Forrester, Apple led its competitors with double-digit gaps, the largest of these being the easy to use category, in which Apple rated 17 points higher than Gateway and 28 points higher than Dell.

Our research shows that good customer experience correlates with customer loyalty for PC manufacturers, writes Temkin. PC shipment numbers in the U.S. reported by IDC on April 14 and Gartner on April 15, however, both counted HP in first place, followed by Dell. Acer was third in the United States, with Apple and Toshiba behind it.

Temkin went on to write, though, that current economic conditions make it difficult to know what the business impacts of customer experience improvements will be.

Temkin and his coauthors, William Chu and Steven Geller, offer four pieces of advice for PC manufacturers thinking about customer experience in these turbulent times.

Good word of mouth can help. The analysts say that while there may not be many growth opportunities, customer experience improvements can certainly cut down on losses. The old adage of the restaurant business applies here: A good experience is shared with one friend, but a bad one is told to 10.

[Don t] give customers a reason to regret their purchase and share those thoughts with their friends, states the report.

Remember that it s a journey. PC manufacturers need to think of their customers' experience as a long-term asset. To build momentum in an economic downturn, the report suggests, focus on several areas, including prioritizing moments of truth, seeking usability improvements and increasing communications with employees.

Maintain an outside-in approach. The analysts recommend manufacturers get to know their customers better and better incorporate their voices into future planning.

Keep an eye on the long term. To maintain a long-term road map toward what Forrester calls Experience-Based Differentiation, or EBD, PC makers should obsess about customer needs, reinforce their brand with every interaction and treat customer experiences as a competence, not a function.

As a whole, the PC manufacturing industry received a score of 64 percent on the Forrester CxPi, with credit card providers (scoring 68 percent) and even airlines (65 percent) ranking ahead of them. Consumers rated their interactions with retailers most favorably, with an average score of 81 percent, followed by hotels (79 percent ) and insurance providers (73 percent).

Laptop Compare

In today's world, it seems that almost any topic is open for debate. While I was gathering facts for this article, I was quite surprised to find some of the issues I thought were settled are actually still being openly discussed.

What kind of computer are you sitting at this very moment? Is it the computer of your dreams or just some junker that you've been making due with? The reason I ask is because there are tons of options out there these days. There's no reason why you have to settle for a Tandy 1000. Okay, so you're probably not punching away at a Tandy 1000, but my point concerns price. When it comes to computer prices now days, they vary greatly. Have you browsed the newest computers lately? I'll bet that perfect PC or Mac is waiting, but you simply haven't taken the time to do a laptop compare online. Yep, that's where the information is folks.

It's really a good idea to probe a little deeper into the subject of Laptop Compare. What you learn may give you the confidence you need to venture into new areas.

When was the last time you did a quick laptop compare at the local electronic superstore? I did this just yesterday. I admit, I'm a computer nut. It's a blast seeing how things change so rapidly. I'm constantly amazed at the new and improved additions and accessories. I mean come on, who couldn't use another computer? Yesterday while browsing through Best Buy, I noticed some cool deals on Sony laptops and notebooks. I regret not giving these a fair shot. They look so upper-scale, but lack the hefty price tag. You can't beat that. Once I had finished my laptop compare in Best Buy, it was off to Circuit City. They also had a nice selection of computers to sort through. In the end I still prefer doing a laptop compare and search online. The World-Wide-Web always has the most to sift through. Not to mention the great prices found in cyberspace. Before I purchased my Mac Ibook G4, I decided to do a little background research. I was able to do a laptop compare using the various review sites. This was rather informative to say the least. It was interesting hearing loads of reviews regarding several different computers.

If you are trying to do a laptop compare, then I suggest the Internet first. Don't listen to the sales pitch from the guy at the Dell booth, or Mac store. He will just push his product in your face. Remember, he wants to make that commission. When it comes down to purchasing a computer, you need to do some recon on your own. It's imperative to know what you want the PC or Mac to accomplish before buying it. This is so simple now days. Hop online and do a laptop compare now.

Now you can be a confident expert on Laptop Compare. OK, maybe not an expert. But you should have something to bring to the table next time you join a discussion on Laptop Compare.

eBay Releases IPO Plan for Skype

eBay decides to spin off VOIP company Skype, with which it has a decidedly uneven relationship. An IPO is planned for the first half of 2010, although eBay says the specific timing of the IPO will be based on market conditions.

Online auction house eBay is making it clear that it expects VOIP company Skype, which the company acquired in 2005 for $2.6 billion, to start pulling its own commercial weight. April 14, eBay announced plans to separate Skype from the company, beginning with an IPO intended to be completed in the first half of 2010.

The company released a statement saying the decision to separate Skype was based on a timeline outlined by eBay s president and CEO, John Donahoe. At one point, the company said it would spend a year evaluating Skype and its potential synergies within the eBay portfolio before making any decisions about Skype's future. Donahoe said it is clear that Skype has limited synergies with eBay and PayPay, eBay s online payment service.

"Skype is a great stand-alone business with strong fundamentals and accelerating momentum," Donahoe said in a prepared statement. "We believe operating Skype as a stand-alone publicly traded company is the best path for maximizing its potential. This will give Skype the focus and resources required to continue its growth and effectively compete in online voice and video communications.

In 2008, Skype generated revenues of $551 million, up 44 percent from 2007, and segment margins of approximately 21 percent. Registered users reached 405 million by the end of 2008, up 47 percent from 2007. eBay has said it expects Skype to be a billion-dollar company by 2011, nearly doubling 2008 revenues. However, eBay has written Skype down to $1.7 billion on its books. Donahoe said separating Skype will allow the company to focus entirely on its two core growth engines e-commerce and online payments.

There were signs earlier this year that eBay was focusing more intently on Skype, which allows users to make calls for free (Skype-to-Skype accounts) or to call mobile phones and landlines for very low rates, aiming to expand the usage of Skype for business purposes. Donahoe also installed a new management team at Skype led by Josh Silverman, which the company said has driven stronger momentum and improved performance.

In March, Skype announced Skype for SIP a beta program for a limited number of users that will bring VOIP (voice over IP) service to the office PBX. Some analysts have suggested that as PBX systems reach retirement age, Skype is positioned to enable enterprises to make better use of existing SIP PBXes and to alter the impression of Skype s capability in the business world.

Skype also made two other large announcements in March, one pertaining to the upcoming availability of Skype on BlackBerry smartphones, widely used by business professionals, and the other about the availability of the service on Apple s popular iPhone and iPod Touch.

More than 1 million people downloaded Skype for iPhone in the first 36 hours after it became available and eBay reported Skype immediately became the No. 1 downloaded free iPhone application in more than 40 markets, including the United States, United Kingdom and Japan. One week later, downloads passed the 2 million mark, putting Skype on more than 6 percent of all iPhones and iPod Touches and added almost half a million new Skype users in the process.

5 Steps To Removing PC Clutter

It s hard enough as it is these days to get organized and then remain that way for weeks and months down the road. We are all very busy people, some of us with 9-5 jobs and one hour commutes, and others of us busy making our lives at home work for us, with children at tow and a variety of chores to do as well as errands to run.

However, no matter how vastly different our lives may be, we all run into the same problems when dealing with organization, and that s: KEEPING organized. need to develop a system that helps your PC remain free of clutter and organized. Granted, this task doesn t come easy at first, but all it takes is a few extra steps each day, done consistently, that will maximize your results in the long run.

So, let s say you have disorganized files all over your hard drive that you have difficulty finding when you need them. Your PC keeps catching viruses out of the blue. You don t know what to do with all your spam mail. You have extra programs and freeware on your PC that you don t know anything about, and even if you did, wouldn t know what to do with them. Here are a few steps to help you get started in the right direction:

1.) Get rid of any unnecessary files or programs that are on your hard drive. This requires a little homework on your part. You ll need to set aside the time to sit down and actually take a look at all of the files on your PC and delete what you don t need. A few things to do periodically for optimal performance is to run a disk cleanup, use your system file checker, and defragment your hard drive.

2.) Organize all of your files and folders. Once you ve deleted everything you don t need, take a look at what s left. Is there some way you could organize these in nice categorical folders, so that it s easier to retrieve them later on? For example, you could create a few folders underneath your My Documents folder, and give then names such as: My Journal, My TV Shows, My Videos, My Business, My Songs, My JobFind, etc. You could then place all respective files underneath these neatly organized folders. You can also take advantage of many of the folders already supplied to you by Microsoft Windows, such as My Pictures and My Music.

3.) Install adware and spyware programs. I don t think I need to stress how important it is to run antivirus and spyware software. I personally like McAffee because of its wide range of protection services, but Norton AntiVirus works great as well.

4.) Delete unnecessary shareware and freeware files. It s very important to keep your hard drive as clean and organized as possible. Remember that shareware and freeware can potentially be harmful to your computer (viruses!), depending upon which source you received your shareware from.

5.) Delete unnecessary emails and take control of spam. By now, you know to have antivirus software installed on your PC. That s a must, and will protect you if you should happen to open emails that have viruses attached to them. Before you open any of your emails, check to be sure you know the sender, and that there are no .zip or .exe attachments. Be very careful about opening files with attachments, especially from senders you don t know.

Hope many of these tips will you help you move toward the right direction in de-cluttering your PC, now and for good.

AMD vs. Intel: Which Chip Offers More Bang for Your Buck in Gami

Computer enthusiasts have long known of the ongoing rivalry between Intel, the processing giant, and Advanced Micro Devices, or AMD. Since the early nineties, Intel and AMD have vied for technical dominance in the computer hardware field and in relation to computer gaming. For many years, AMD was like the kid brother" of Intel the latter held a seemingly insurmountable lead in terms of market share, and the former simply eked by and scrappily etched out a place in the industry for itself. Intel was also traditionally associated with more powerful chips while AMD came to symbolize greater value. Back in the nineties when clock speed meant everything, Intel s Pentium III chip always managed to maintain a sizeable lead in terms of performance and speed over AMD s Athlon offering. Product support also tended to lean decidedly in Intel s favor largely due to their history of success, there were no shortage of computer manufacturers ready to do business with the company. AMD, meanwhile, enjoyed an almost cult-like following amongst computer enthusiasts who lauded its price-to-performance ratio.

Eventually, however, the raw power of a processor began to be less important than its overall performance, information processing ability, and power consumption. The landscape began to really shift in about 2000. That year, AMD announced and began to develop its 64-bit line of processors, Opteron and Athlon 64. The company essentially staked its future on these chip lines, and in 2003 they released to much acclaim. The balance of power had shifted decidedly in the processor market while Intel s Pentium 4 chips struggled with power consumption and heat issues as they steadily increased in clock speed, AMD s 64-bit offerings allowed consumers to take advantage of more powerful 64-bit code in their systems including gaming systems. Whereas Intel enthusiasts could always point to the performance discrepancy between the two different types of chips, AMD quickly became the processor of choice for computer gaming and computer hardware enthusiasts. The processing power provided by the 64-bit AMD chips proved to be too great to pass up, and this was only reinforced in 2005 when the company released the first dual-core processors to the market. Since then, Intel has been playing catch-up in terms of hardware availability, and AMD s market share has reached its highest point at roughly 20 percent, according to eWeek.com.

What are the Advantages of AMD Processors?

As the processing landscape has shifted towards AMD s side, there are some key benefits of using AMD-based hardware that have been revealed. The first is obviously the pure power edge that AMD has attained. Tom s Hardware (tomshardware.com) has long been regarded as a reliable authority in the field of computer hardware reviews. While Intel for years could always claim performance superiority over AMD at the high end, Tom s reports that this is no longer the case. In conclusion to a comparison between AMD s dual core Athlon FX-60 processor and Intel s Pentium Extreme Edition, the reviewer writes, With the exception of a few audio and video encoding benchmarks, the Athlon 64 FX-60 represents the new device to beat as far as performance goes, thanks to its two processing cores." Furthermore, the reviewer adds that the increased demands of running dual graphics cards configurations means that this processor is a great choice for the best-possible 3D gaming experience." This status as the most powerful processor is reinforced by the fact that Alienware, renowned as the industry leader in terms of powerful custom computers, uses the FX-60 exclusively in its top-of-the-line Aurora ALX system.

Another advantage of AMD processors over Intel, at least for the time being, is the lower relative power consumption of their systems. According to Tom s Hardware, AMD s Turion 64 enjoys its status as the most efficient single core processor, and while Intel s Core Duo is technically the most efficient dual core processor, the overall power efficiency of AMD systems offsets any advantage that the Core Duo might have. When you subtract the power draw of a graphics card, which can be massive, it remains clear that AMD processors just do their job in a more efficient manner.

So What about Intel?

None of this means that Intel processors should be completely disregarded, however. One key advantage that Intel maintains is in sheer numbers. Intel still maintains a roughly 80 percent share of the market today, and as such you are more likely to find a system sporting an Intel processor rather than its AMD counterpart. Furthermore, Intel s long string of dominance ensures that there are no software-hardware compatibility issues as Intel is the accepted leader in the processor industry, companies base their compatibility around Intel processors first.

It s not as if Intel is resting on their laurels, either. As has often happened during the rivalry between Intel and AMD, competition is breeding a new level of performance. Intel has recently shifted to a 65 nm processor core process, beating AMD to the punch in the process. The reduced core size allows for greater possibilities in terms of chip efficiency and power. Intel s top-level chip is still more expensive than its AMD counterpart, however, perhaps due to the relative newness of the 65 nm process.

So Which Chip Should you Buy for Your Gaming Computer?

All of these technical comparisons are well and good, but they don t answer the fundamental question: which chip is best for computer gaming systems? Though they continue to use the 90 nm core process for the time being, AMD processors still represent the best bang for your buck." AMD s highest-end chips are still priced lower than their Intel counterparts, and the performance numbers available for them don t lie. Furthermore, AMD-based systems are more power-efficient in general, and certain technologies allow for technical innovation. nVidia s nForce line of motherboards, for example, is just on the verge of achieving steady dual-channel DDR2-667 memory support for Athlon 64 FX2 dual core chips. What this means for the consumer is that the memory will operate faster, with a higher bandwidth, and in greater harmony with the processor than ever before.

Steps To Increase Replacement Laptop Computer Battery Lifespan

Many times you wonder why your replacement laptop computer battery dies so quickly and if there are any precautions you can take to avoid this problem. If you care for and maintain your batteries properly, you can easily extend the lives of your laptop computer replacement batteries. It can be frustrating when you purchase a replacement battery for your laptop and after a few months the battery life has significantly declined. This is not what you want to happen. Below are some simple steps that can be taken to ensure that your battery lasts for its maximum potential.

If you constantly remove your replacement battery from the laptop and store it away it can ultimately become soiled, and no longer functional at peak capabilities. To alleviate the problem of a soiled battery, take a cotton swab and Isopropyl alcohol to rub down the laptop battery. When cleaning the metal connectors be sure to always use a dry cloth. While cleaning the contacts you should use the Isopropyl alcohol. This will properly clean your replacement laptop battery. Having clean contacts helps maintain a good connection between your battery and notebook computer. The optimal place to store your laptop battery is in a cool, dry place that is away from excessive heat. Make it a point to keep the laptop battery away from any form of extreme heat. Heat is a batteries enemy, so avoiding heat is very advantageous to your batteries lifespan. Also make sure that the battery is not near any metallic objects that can disrupt the batteries charge. It is not uncommon for Lithium-Ion batteries to discharge after extended periods of being stored.

It is a good idea to exercise any replacement laptop batteries at least once every two to three weeks. Exercising a laptop computer battery means using the battery and not leaving it dormant for extended periods of time. If the laptop battery is not used for extended periods of time it is highly recommended to exercise it in-between down times. This will prevent significant battery capacity loss. By following this simple step your laptop battery will be able to store more of a charge than if otherwise left alone. If you do not use the laptop battery frequently then you should exercise it before attempting to use it regularly.

If you are using an AC Adapter to power your computer then it is advisable to remove the good battery from your notebook and replace it with an old, short run-time battery. This is a good practice as the battery in the laptop will continuously be charged and discharged rendering the battery life shorter than ever expected. Excessive charging and recharging of batteries drastically shortens battery life. Thus, it is a good idea to remove that brand new battery from your laptop when it is being powered through the AC Adapter.

Utilizing your laptops power management features prior to use can extend the life of your battery. Defragmenting your laptop is beneficial to your computers performance along with its battery life. Having a clean, defragmented notebook ensures that the laptop will run in an efficient manner. Having a laptop computer run efficiently will increase the batteries life span, by not draining it trying to reach programs. All these simple tips can ensure that your replacement laptop computer battery will have an extended lifespan

Windows Vista: Running the Add Hardware Wizard

Windows detects most hardware you install, but if Windows doesn t detect a device, you can run the Add Hardware Wizard to add the hardware manually. To run the Add Hardware Wizard, take the following steps:

1. Press Windows Key+Break. Windows displays a System window.

2. In the Tasks panel on the left, click the Device Manager link, and then authenticate yourself to User Account Control. Windows displays a Device Manager window. For more detail on Device Manager, see the section Opening Device Manager, later in this article.

3. Click your computer s name at the top of the tree, and then choose Action Add Legacy Hardware. You can also right-click your computer s name and choose Add Legacy Hardware from the context menu. Device Manager launches the Add Hardware Wizard, which displays its Welcome to the Add Hardware Wizard screen, as shown here.

4. Click the Next button. The wizard displays the The Wizard Can Help You Install Other Hardware screen, as shown here, offering to search for the hardware.

5.Select the Install the Hardware that I Manually Select from a List option button.

6. Click the Next button. The wizard displays the From the List Below, Select the Type of Hardware You Are Installing page, as shown here.

7. In the Common Hardware Types list box, select the type of hardware you re installing. If the device doesn t fit any of the descriptions, select the Show All Devices item.

8. Click the Next button:

If you chose the Show All Devices item, the wizard displays the Select the Device Driver You Want to Install for this Hardware page, as shown here.

If you chose a specific type of hardware, the wizard displays a list of that type of device. The following illustration shows a list of infrared devices.

9. If Windows has a driver for the device, select it by clicking the manufacturer in the Manufacturer list box and the device in the Model list box. If you have a new driver, click the Have Disk button and use the resulting Install from Disk dialog box to specify the location of the driver.

10. Click the Next button. The wizard displays the The Wizard Is Ready to Install Your Hardware page, listing the hardware that s lined up for installation, as shown here.

11. Click the Next button. The wizard installs the hardware and displays the Completing the Add Hardware Wizard page.

12. Click the Finish button. The Add Hardware Wizard closes itself. The hardware should be ready for use.

Working with Hardware Drivers

Without a functional driver, Windows can t use any piece of hardware. And using the wrong driver or a badly written driver can make Windows unstable or even make it crash. Hardware manufacturers frequently release new versions of drivers for their hardware to improve performance, to banish bugs, or both. If you want to keep your hardware running to the best of its capacity, check the manufacturers sites and the Windows Update site for updated drivers. In theory, Windows Update should be able to supply you with the latest drivers for most of your hardware. In practice, you can probably get the latest drivers more quickly by haunting the hardware manufacturers websites and newsgroups. To view, change, or uninstall the driver for a device, display the Driver page of the Properties dialog box for the device. The easiest way to display the Properties dialog box for the device is to go through Device Manager, which you will have met earlier in this article if you ve been following along.

Opening Device Manager

To display the Device Manager window, take the following steps:

1. Press Windows Key+Break. Windows displays a System window.

2. In the Tasks panel on the left, click the Device Manager link, and then authenticate yourself to User Account Control. Windows displays a Device Manager window .

Device Manager presents a categorized tree of the devices on the computer in its default view. Any device that isn t working or has a problem is marked with an exclamation mark icon, like the RAID Controller and the Unknown Device that appear in the Other Devices category. When all is well with a category of device, Device Manager presents the category collapsed. You can change the view by displaying the View menu and choosing Devices by Type the default view, Devices by Connection, Resources by Type, or Resources by Connection from the menu. You can display hidden devices by choosing View Show Hidden Devices. If you leave Device Manager open while you plug in a hot-pluggable device, you may need to refresh the listing in Device Manager to make it list the device. To do so, click the computer s entry at the top of the tree, and then choose Action Scan for Hardware Changes. To check or set properties for a device, double-click its entry in Device Manager or right-click the entry and choose Properties from the context menu. Windows displays the Properties dialog box for the device.

Checking the Details of a Driver

The Driver page of the Properties dialog box for a device shows some details of the driver: the provider of the driver the company that supplied the driver to your computer, the date, the version, and the digital signer - the owner of the digital certificate applied to the driver. To display further information, click the Driver Details button. Windows displays the Driver File Details dialog box, which displays further information: the filenames and paths of the driver files, the provider the company that originally provided the driver, the file version, the copyright information, and the digital signer again.

Updating a Driver

To update a driver, click the Update Driver Software Wizard on the Driver page of the Properties dialog box for the device. If you have a specific driver to install, follow the process explained in the section Specifying a Driver Manually, earlier in this article. If you re just checking for a new driver on Windows Update, click the Search Automatically for Updated Driver Software button.

Rolling Back a Driver

If a new driver you ve installed doesn t work, or doesn t improve things, revert to the previous driver by using the driver rollback feature. To use the rollback feature, click the Roll Back Driver button on the Driver page of the Properties dialog box for the device.

Disabling a Device

If you want to stop using a device temporarily, you can disable it. For example, you might want to disable a device that you think is making Windows unstable. To disable a device, right-click it in Device Manager, and then choose Disable from the context menu. Windows displays a confirmation message box, such as that shown here. Click the Yes button. Windows closes the message box and disables the device.

Uninstalling a Device

If you want to stop using a device permanently and remove it from your computer, uninstall it first. To do so, follow these steps:

1. In Device Manager, right-click the device, and then choose Uninstall from the context menu. Alternatively, display the Properties dialog box for the device, and then click the Uninstall button on the Driver page. Windows displays the Confirm Device Uninstall dialog box, as shown here.

2. If you want to remove the device s driver as well as the device, select the Delete the Driver Software for This Device check box. Normally, it s best to leave the driver on your computer in case you install the device again, but if you re sure you won t reinstall it, you may want to reclaim the small amount of disk space the driver occupies.

3. Click the OK button. Windows closes the dialog box and uninstalls the device.

Adding Specific Hardware Items

The following sections discuss considerations for adding particular hardware items that need configuration beyond the driver. Many hardware items do not. The easiest place to start configuring most hardware items is Device Manager.

Apple Flagship Stores Selling 90 iPhones Daily

Research group Piper Jaffray counted sales of Apple iPhones, Macs and iPods in various retail locations and offers some interesting numbers, along with predictions for Apple sales going forward. In flagship stores, Apple sells about 90 iPhones each day, compared with the 16 sold each day in its retail stores.

Apple sells an average of 90 iPhone 3G handsets, 123 Macs and 240 iPods per day in its New York Fifth Avenue location and other flagship stores though in an average retail store, those numbers drop to 16 iPhones, 20 Macs and 27 iPods.

These numbers were compiled in an April 15 research note from research outfit Piper Jaffray.

Piper states it spent 25 hours counting iPod, iPhone and Mac sales in Apple retail stores throughout the country during the second week of April.

Based on what it saw, it is predicting that iPhone units will be flat to down 15 percent on a sequential basis in the March 2009 quarter. While iPhone units per day per store dropped during the period from Nov. 28 through March 22, the company believes expanded international availability in recent months takes some pressure off of domestic Apple stores.

During a March check, Apple sold approximately 22 iPhones per day in a single store, versus 28 iPhones per day in a November 2008 check.

Mac units are expected to be in-line or slightly above estimates of 2.2 million in the March 2009 quarter. On a quarter-to-quarter basis, Piper Jaffrey is modeling for a sequential decline.

But Apple is selling 28 Macs [per day] on average, indicating [a] slight upside, according to Piper.

During the time of the company s checks, Apple had released its updated Macs, with new Intel processors. Though Piper expects the impact of new models may show its checks to be only slightly overstated.

During March counts, the average Apple store sold 28 Macs per day, versus 36 during November 2008.

This year was the first that Piper counted iPods, so it couldn t offer year-to-year comparisons, but its checks showed iPod numbers to be twice that of iPhones, which was in line with its modeling.

We believe the iPod number should be in-line with Street estimates of [approximately 10 million] units, helped by the 3/11 launch of the iPod shuffle, stated the research note.

An April 8 research note from Kaufman Bros. analyst Shaw Wu anticipated a June or September quarter rollout of new iPhone hardware, most likely to coincide with the Worldwide Developers Conference in June.

Wu further predicted that two new iPhone models were likely one with an improved processor and extended battery life, and a less expensive junior version with limited functionality.

Apple NAND Flash Chip Order Points to 32GB iPhone

Apple reportedly ordered a large NAND flash chip shipment from Samsung, says a research note from Lazard Capital Markets. The 16-gigabit chips point to the likelihood of a 32GB iPhone, as well as a positive impact to the NAND industry, which includes Toshiba and SanDisk.

Apple has ordered 100 million units of 8-gigabit and 16-gigabit NAND flash memory chips, mostly from Samsung, according to an April 13 research note from Daniel Amir of Lazard Capital Markets.

The chips will likely go toward the new iPhones Apple is preparing to launch in June, according to the report.

The majority of the order is expected to favor the 16-gigabit memory chips, CNET reports, signaling that a 32GB iPhone is in the works. Amir predicted the latter in a March 31 note, along with a low-end 3G version or junior iPhone, as Kaufman Brothers analyst Shaw Wu has called it.

The two new iPhones are expected out in June, likely at the Apple Worldwide Developers Conference in San Francisco, which starts June 8.

Amir s research note, primarily focused on the semiconductor market, additionally noted that Toshiba is expected to lower its wafer load in the second quarter to 60 percent, compared with the 70 percent of the first quarter.

In March, SanDisk units increased 15 percent, and Lazard expects a further increase of 10 to 20 percent in April.

Toshiba and SanDisk have joint ventures. In October 2008, Samsung Apple s main iPhone chip provider withdrew a bid to purchase SanDisk, after Toshiba and SanDisk announced an agreement that turned over 30 percent of SanDisk s share of its manufacturing capacity for its joint ventures with Toshiba to Toshiba.

Samsung said the move created a quarter-billion-dollar operating loss, and made SanDisk s profile more risky.

Apple Fourth in U.S. PC Shipments, Despite Higher Mac Prices

Gartner PC shipment numbers put HP in the top position in the U.S. market for the first time since 2001. In the U.S., HP was followed by Dell, Acer, Apple and Toshiba. Netbook sales were a boost to overall numbers, though Apple, despite not offering one, still performed commendably.

Gartner is reporting a 6.5 percent decline in worldwide PC shipments for the first quarter of 2009, according to numbers released on April 15 that put the quarter s figure at 67.2 million units shipped.

In terms of worldwide numbers, Hewlett-Packard took the lead over Dell, with 19.8 percent of the first-quarter market share, to Dell s 13.1 percent. With a 13 percent share, Acer ranked just behind Dell which this calendar year has released a spiffy, ultra-thin laptop, a lineup of enterprise solutions, and intentions to debut encrypted solid-state drives and a new mobile security suite.

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Fourth place went to Lenovo, with 6.6 percent of the first-quarter market share, and Toshiba followed in fifth place, with 5.5 percent market share.

In the U.S. market, everyone held their same positions except for Lenovo, which was bumped from the equation and replaced by Apple, with a fourth-place U.S. market share of 7.4 percent for the first quarter of 2009 a figure that represents a 1.1 percent loss from the first quarter of 2008.

Gartner reports that Apple s relatively higher average selling price for Macs created challenges for it in the tough economy, but that its deft control of inventories limited its shipment decline.

IDC also recently reported first-quarter PC shipments numbers, giving Apple a slightly more generous 7.6 percent market share, though dropping its market share by 1.2 percent from the first quarter of 2008.

The lower ASPs of mininotebooks and netbooks, such as those offered by HP, Acer and Toshiba, helped to keep PC shipments in the United States somewhat stabilized. The 3 percent fall in shipments, notable in a struggling economy, was attributed to a move by consumers to more portable, and less expensive, devices.

Were Apple to also offer a netbook, with a lower ASP than its current offerings, its market share would likely increase significantly.

7 Barebones Computer Buying Tips

Getting a new computer should be a cool thing, especially a cheap computer. After all that time struggling with you old machine, probably fighting with it to get the latest software to run, your new computer should be a ray of light for your computing future.

Oh, if it were that simple. If things were really that easy or simple when buying a cheap computer, life would be much easier, but just like every other thing, its not that simple.

Barebones computers

have become extremely popular, and for good reason. Getting a barebones computer which does not include a monitor and comes with the bear minimum of parts makes them an upgradable, practical and cheap computer.

But not all things are rosy in barebones computer land...

1. Missing parts

Although barebones computers do come with the essential pieces, most people need at least one or two extras for their day to day barebones system. This is simply due to different applications people use them for. Don t get caught missing that extra part from your barebones system that you then need to get later. You still need to do some homework and research to find out what you really need from your barebones system.

2. Super cheap computer deals

Beware, many corners can be cut to get those sub $200 dollar barebones systems. They can be great, but not always, carefully analyse the components of the package. Also remember that a barebones system couldn t possibly include a monitor for that price, which adds a lot to the price.

3. Mismatched parts

This could become a problem if building your own computer, but it even happens in pre-assembled barebones computer deals. There is a chance that you get something that doesn t fit with the barebones system. There are lots of different connections and speed ratings between parts. Make sure the ones you get match up to the other parts and your needs. Although not common, incompatibilities between parts are not unheard of.

4. Outdated components

To get super-cheap deals older parts are sometimes used in cheap computers. Although this can be a great cost-saver and some old parts are fantastic, there is nearly no chance of an upgrade without putting a major amount of money into your barebones computer again, perhaps as much if not probably more than you paid for your great deal.

5. Defective parts

Although this is another one that has gotten better as the competition has gotten stronger, there is a chance of defects in cheaper products. Your motherboard could be faulty, your power supply might give up after a month or two. These may not be intentional problems, but come hand in hand with "cheap computer stuff".

6.Refurbished computer parts

Refurbished computer parts are a great way to save some money. Not always the biggest saver, but there can be problems with the updates to these computers in much the way as mismatches happen in barebones systems. Often the computer is slightly updated to meet needs, but is really quite an old model, just with upgrades. Can be fine, but the parts they replace might be replaced with something newer but inferior.

7. Claims of great warranty

To try and entice you into feeling safe, offers of long warranties are made. Most of the parts in the computer could have past their warranty dates, so the warranties are purely from the company that put the computer together. They can be hard to contact and take their time to get replacements to you as well as expect you to mail the computer to them so that they can do the repairs.

Barebones computers can be a great way to put together a second computer, build a computer

for simple purposes, like writing documents and casual web surfing. Barebones fit perfectly as a second computer. Just keep these things in mind and you won t get bitten by the bargain bin monster.

Britec Basic Guide To Pc Computer Upgrades and Laptop Upgrade

There comes a time when your computer or laptop is just not performing as well as it used to. And since every computer or laptop owner needs his/her PC to perform multi tasks efficiently and as quickly as possible, so you think your computer or laptop is destined for the scrap heap. However, before tossing it on the scrap heap and spending a lot of money on a new PC system, perhaps you should consider some new upgrades. You will likely spend a lot less money on upgrading your notebook or computer and after the upgrade you should see big improvements in performance sometimes up to 50%. With that being said, here are three upgrades users choose for their computers and laptops.

Notebook s and computer s memory is an essential component of its internal operating system. Memory upgrades probably rank as one of the most popular upgrades for computer and laptop owners. It is also a pretty simple upgrade and one of the quickest, easiest things that you can do to boost your computer s productivity and performance and that can only be a good thing plus it s a lot cheaper than buying a new PC or laptop.

If you are planning on upgrading your laptop or computer s memory, you will first need to determine how much memory your computer currently has. You will also need to find out the speed of your ram and also you will need to know how many empty slots you have for upgrading the memory. Example: If there are no free slots left and you have...let s say two banks with two sticks of 512 megs of ram in the motherboard, a possible solutions is to remove both sticks of ram and replace the memory with two sticks of 1 gig ram...that s only if the motherboard can take 1 gig sticks? But remember this is only if the both banks are full? If your computer was new when you purchased it and you have not upgraded it yet, the information is normally provided in the user manual that came with your system. Or you can use programs such as Sandra 2008, SIW - System Information. Otherwise; you will need to perform a BIOS check to see how much memory you currently have. Then you will also need to open your computer s case to check the number of empty slots.

(PC S only) Another popular upgrade many people consider when there upgrading their systems is the processer (CPU) upgrade. Most custom built computers have room for a bigger CPU on the down side for people who brought a branded PC say from PC World...it s unlikely your be able to upgrade the CPU by much if any, this is their way of making you buy a new computer.

(PC S only) If you love playing all of the high graphic intensive games that are about in the shops, you may want to treat yourself a more powerful video card; this is a very popular computer upgrade for hardcore pc game lovers. Some of the newest games need a mid to high end graphics card to play them at full level, all though the game has a card requirement to even play the game this is just a requirement to play the game at a low spec.

Choosing a video card can be a little confusing, though, because there are so many on the market. You will first need to check either your computer manual

or motherboard to determine which video cards are compatible with your system. Ask a computer specialist to explain the differences between the video cards if you are uncertain about your choice.

These are only a few of the most popular upgrades for computers. Some others include PSU, Sound Card, DVD-RW, Hard Drive and Motherboard upgrades. Before scraping your old computer for a new one, be sure to ask a professional for prices and his opinion to see if an upgrade might be a more cost effective option then buying a new PC if you decide to get a new computer I would advise to get a custom built computer and not one bought from a shop. I hope this basic guide helps you out.

Trouble-shooting Hard Drive Problems - Part 2

The following article is the second in a series that helps solve many of the common boot problems with hard drives.

The article explains how to reconstruct the Volume Boot Record and will touch briefly on multiple-partition drives. This information will help solve some very common problems encountered in a computer service department. This article is designed to work with a system that has a single drive using a FAT 16 structure (all DOS and older Windows systems, some Windows NT), and no drive overlay.

A common problem with hard drives is the error message "MISSING OPERATING SYSTEM."

Typically what this means is that critical data is missing or damaged in two possible locations. The first is the Master Boot Record (MBR). This data area contains error messages and pointer information that specifies the location of the second critical data area, the Volume Boot Record (VBR). The VBR contains the operating system specific data for the format of that particular partition on the drive. If either of these two critical data areas is damaged, by a virus, controller failure, etc., then the drive will not be accessible through the operating system.

The normal response to this error message is to boot to a floppy disk and to re-partition the drive (probably using FDISK) and thereby totally removing any possibility for recovery of the data on that drive, except by dedicated data recovery software or a data recovery facility. If applicable, the following technique will help save time, money, and frustration.

The first step to data recovery (covered in great detail in the first article of this series) is to verify the location of the existing partition information. For the purposes of this article, it will be assumed that the FAT structure and the root directory are intact, there is only one partition, and that only the MBR and the VBR were damaged. Using Micro-Scope, enter the Fixed Disk Editor menu and select the fixed disk that is being repaired. Using the Find menu option, locate all the sectors that contain the string "55 AA" (see Step Four of the first article in this series), and then verify that the FAT structures are intact (see Step Seven). Note on a scratch paper the values (in Cylinder, Head, Sector format) where this string appears. These values will be used later in the reconstruction process.

Rebuilding the MBR

Using the Fixed Disk Editor in Micro-Scope, locate and read Cylinder 0, Head 0, Sector 1. This should be the location of the corrupt Master Boot Record. Press "M" to modify the sector and enter 0 s for the entire sector, effectively wiping all the data from this sector. Press ESC, then "W" to write the data, and "Y" to confirm the write operation. Then exit the Fixed Disk Editor and select the Rebuild Master Boot Record menu option. Press "Y" to confirm this operation. The fixed drive now has a completely corruption-free MBR available for use during the reconstruction of the VBR.

Rebuilding the VBR

There is a simple method for rebuilding the VBR. Copy the data from a like fixed disk or a similar-sized fixed disk with the identical operating system (the versions must be the same.) There are two approaches for obtaining this data. The first is to install the second drive in the system, reboot Micro-Scope, and copy the sectors directly from the "healthy" drive to the drive being reconstructed. The second method is to copy the sectors from the "healthy" drive to a floppy diskette and transfer that diskette to the machine containing the drive being reconstructed. The data can be copied to any sector on the floppy disk. Just note where this data is stored on the floppy disk so that it may be easily retrieved when copying it back to the drive being reconstructed. In either case, the VBR is located at Cylinder 0, Head 1, Sector 1 on the "healthy" drive. Copy this data to the same location on the damaged drive. Exit the Fixed Disk Editor.

The drive now has a clean MBR and VBR, and with a few modifications to the values stored in these data areas, the drive will be fully reconstructed.

Access the VBR in the Partition Editor. Some of the values in this area will remain the same. These are: Bytes Per Sector, Reserved Sectors, Number of Copies of FAT, Max # of Root Dir. Entries, Media Description Byte, and Volume Boot Signature. Sectors Per Cluster may or may not need to be changed. Put the cursor over this value and press F1 for a formula that will help determine the proper value. Use this same F1 procedure for determining the Total Number of Sectors. This value should be the same as the value for Number of Sectors in the partition table.

The Sectors per FAT value equals the number of sectors from the beginning of the first FAT to the beginning of the second FAT (as described in the first article in this series.) The values for Sectors per Track and Number of Hidden Sectors should be identical to the values in the MBR. The Number of Heads is either the same as the value in the MBR or the same as the value of the Number of Heads in the partition table plus one (refer to the first article in the series for more information on this topic.) After completing this information, the drive should either be bootable or accessible via a bootable diskette. If this is not the case, e-mail the Technical Support department for further verification of the problem.

Reconstructing Multiple Partition Volumes

In some cases, the drive may have been partitioned into smaller, logical partitions. If this is the case, the chance of this data being corrupt is slim, and correct Head and Sector values are readily available from these areas. To find the second partition on the drive, use the Fixed Disk Editor in Micro-Scope to view the sector containing the "55 AA" string. This sector should appear after the first VBR, so don t confuse the two. The second MBR should start on Head 0, Sector 1 of a given cylinder. Accordingly, the second VBR will appear on Head 1, Sector 1, and the FAT on Head 1, Sector 2, etc. By adjusting the first MBR in Micro-Scope so that the value for Starting Cylinder, Head and Sector is equal to the location of the second MBR, the VBR is now accessible through the Micro-Scope partition editor. Use these values to reconstruct the second MBR. The only value that will need recalculating is the Start Absolute Sector in the second MBR.

As outlined in the first article in the series, the Start Absolute Sector is the same as the value for Ending Sector. This is not the case with a second partition. The Start Absolute Sector is the number of sectors prior to the VBR. The formula for the Start Absolute Sector is as follows: (Number of Sectors) + (the Start Absolute Sector of the previous partition) + (Sectors per Track). This formula will work for any additional logical partitions.

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Things to look for when buying a computer microphone

Computer microphones

are a valuable addition to any PC and they greatly increase interactivity and communication levels. You can use a microphone for performing various tasks, both business and fun related. For example, you can hold a conference with your business partners, over the Internet, or you can chat with your friends online, instead of doing that on the phone. Of course, in order to enjoy accurate and high quality communication, you have to choose a good PC microphone. There is a huge variety of models on the market, ranging from microphones that you can buy for a few dollars and going all the way to expensive, high tech desktop microphones. So which PC microphone is right for you?

Price Vs Quality

You can pay $5 for a microphone, or you can pay $50. So where s the difference, apart from the price? Well, cheap microphones have low prices for some good reasons: they offer average to low quality sound, they break down more easily and you can t use them successfully in all applications that support a microphone. The materials they are manufactured from have to be cheap, which eliminates the idea of high quality, so the end product is of lower reliability. And at this price, you can be sure bulk manufacturing is present and quality tests are quick and far from rigorous. Microphones that come for a higher price have, in most cases, better sound quality and more features. Such microphones will have noise canceling filters, which help diminish background noise. Distortion filters and integrated circuits also help keep voice sounds clear and accurate. The materials used for more expensive microphones also last longer plastic doesn t crack so easily and if you drop it on the floor you know that the internal components are well protected.

Choosing the right computer microphone

Determining what price range you are in and what model to purchase depends heavily on the purpose you have in mind for the microphone. Are you going to use it just to chat with friends online? In that case, spending a lot of money on a professional computer microphone is not justified. Do you plan to hold business conferences over the Internet? Then maybe you should get a better microphone that will allow the discussion to be continuous and clear, without noise distortion. Giving vocal commands to your computer or dictating to word processing software with speech recognition

capabilities is another use for desktop microphones. Quality should be first here speech recognition software

is very sensitive and demands a high quality microphone and sound card. Recording your voice and inserting it into music tracks is possible, but a high quality microphone is absolutely essential in this case.

Windows Vista: Setting different PC components and settings

The Properties dialog box for a DVD drive contains a DVD Region page that controls the DVD encoding region set for the DVD player. To change the region, select the country you want in the list box and click the OK button.

Expert Knowledge: DVD Encoding Regions

In case you ve managed to avoid the question of DVD encoding regions: As far as DVDs are concerned, the world is divided into eight regions or locales. Region 1 is the United States, Canada, and U.S. Territories. Region 2 is Europe, Japan, South Africa, and the Middle East. Region 3 is Southeast Asia, East Asia, and Hong Kong. Region 4 is Australia, New Zealand, the Pacific Islands, South America, Central America, Mexico, and the Caribbean. Region 5 is Eastern Europe, Mongolia, North Korea, the Indian subcontinent, and Africa, except South Africa. Region 6 is China. Region 7 is reserved for off-world use, perhaps. And Region 8 is for international vessels such as airplanes and cruise ships. DVD players are encoded to play only DVDs for their region. Almost all DVDs are encoded for the region in which they re intended to be sold. There are also all-region DVDs that ll play in any region. So to play a DVD, you need a player with a matching region code. Most consumer-electronics DVD players are coded for one region only. Some players can play discs for two, more, or all regions. Other players can be chipped modified, either by adding hardware, modifying the built-in hardware physically, or by entering an engineer s code to reprogram the device to play DVDs with different regional encoding or even to play any regional encoding. Chipping is legal in most countries though some manufacturers pretend to disagree but typically costs a proportion of the cost of a cheap DVD player.

PC DVD drives are a little more flexible than most consumer-electronics DVD players. With most drives, you can switch region a certain number of times on a DVD drive before it goes into a locked state in which you can no longer change the region. The DVD Region page of the Properties dialog box for the DVD drive displays the number of times you can change the region again. Use them sparingly.

Why do DVDs have regional encoding anyway? In theory, it s to let the movie studios control the release of the movie in different countries. For example, U.S.-made movies are often released in the United States several months before they re released in Europe, and DVDs and videos of the movie are often released in the United States while the movie is still running in Europe. Regional encoding prevents most of the Europeans from viewing the movie on DVD until it s released with Region 2 encoding.

In practice, regional encoding also enables the distributors to charge different prices for DVDs in different countries without being undercut by imported DVDs from the least expensive regions. For example, at this writing, DVDs in Region 2 are substantially more expensive than those in Region 1, and the European Union has been investigating whether this constitutes price-fixing.

Adding a Removable Drive

The first time you plug in a removable drive or local drive, Windows displays an AutoPlay dialog box offering you choices for what to do with it. The choices Windows offers depends on the content on the drive - for example:

Import Pictures This item appears if the drive contains pictures - for example, digital photos.

View Pictures This item also appears if the drive contains pictures. You may have a choice of using Windows in other words, Explorer or Windows Media Center.

Wireless Network Setup Wizard This item appears if you ve put the setup files for a wireless network on a USB drive. See Article 27 for details.

Open Folder to View Files This item appears if the drive contains document files such as Word documents or Excel workbooks.

Speed Up My System This item appears if the drive is of a type that Windows can use for ReadyBoost see Article 15. Select the action you want to take. If you want Windows to take this action for every device you add that contains this type of file, select the Always Do This For check box this check box names the type of content involved - for example, Always Do This for Software and Games, or Always Do This for Pictures. Then click the OK button. Windows closes the AutoPlay dialog box and takes the action you specified.

Adding a Modem

Windows automatically loads the driver for a USB modem, a PCI modem, or a PC Card modem if it can find the driver. With a serial modem, however, things are more hit and miss: If you connect the modem before powering on the computer, Windows may notice the modem and load the driver for it assuming it can find the driver. But if you connect a serial modem while the computer is running, Windows tends not to notice the modem, even if you run the Add Hardware Wizard from the Device Manager window. To force Windows to detect a serial modem, follow these steps:

1. Choose Start Control Panel. Windows opens a Control Panel window.

2.In Control Panel Home view, click the Hardware and Sound link. Windows displays a Hardware and Sound window.

3. Click the Phone and Modem Options link. Windows displays the Phone and Modem Options dialog box.

4. Click the Modems tab. Windows displays the Modems page .

5. Click the Add button, and then authenticate yourself to User Account Control. Windows launches the Add Hardware Wizard, which displays the Install New Modem screen, as shown here.

6. Make sure your modem is powered on and that no other program is using it. If Windows doesn t know the modem is there, no program should be able to use it.

7. Clear the Don t Detect My Modem; I Will Select It from a List check box.

8.Click the Next button. Windows attempts to detect the modem. You ll see a notification-area pop-up message saying that Windows is installing the modem.

9. The wizard should display a screen saying that the modem installation is finished. If it does, click the Close button to close the wizard. Sometimes, however, the wizard fails to notice the modem even though Windows is installing the driver software and then displaying a notification-area pop-up saying that the modem has been installed. If this happens, cancel the wizard, and then verify that the modem appears on the Modems page of the Phone and Modem Options dialog box.

Specifying Your Location

The first time you try to use a modem, Windows displays the Location Information dialog box demanding your location information unless you ve given it already. Specify the details: your country and region; your area code or city code; any carrier code you need to enter; any number you dial to access an outside line; and whether the phone system uses tone dialing the norm for most modern exchanges or pulse dialing. Then click the OK button. Windows closes the Location Information dialog box.

Specifying Phone and Modem Options

After you close the Location Information dialog box, Windows displays the Phone and Modem Options dialog box with the Dialing Rules page foremost. Windows provides you with a default location named My Location with the area code you specified in the Location Information dialog box. Rename this location to something descriptive for example, Home or the name of the city or town. Click the Edit button and enter the new name in the Location Name text box on the General page of the Edit Location dialog box that Windows displays. Then click the OK button. Windows closes the Edit Location dialog box. Click the OK button, and Windows closes the Phone and Modem Options dialog box. For a laptop or other computer you take traveling, you ll probably want to create other locations as well. Article 14 discusses how to do this.

Adding a Video Card

When you install a new video card, Windows may detect it on boot-up and display the Found New Hardware Wizard so that you can install the correct driver for it. Other times, you may have to change the video driver manually by using the Update Driver Software Wizard. After installing the driver for the new video card, you usually need to restart Windows. When you log back on, Windows displays the Display Properties dialog box so that you can test and apply the screen resolution and color quality you want. See Article 3 for a discussion of how to choose a suitable screen resolution and color depth.

Adding a Monitor

Adding a monitor tends to be simplicity itself, involving only a couple of cables. But Windows often identifies a monitor simply as Plug and Play Monitor and assigns it a generic driver. This driver works well enough for undemanding programs, but to get the best performance, use the Update Driver Software Wizard to install the latest driver for your specific type of monitor. If you re seeing corrupted images on your monitor, or if the mouse pointer doesn t respond properly to conventional stimuli, or if DirectX isn t working, you may need to change the graphics hardware acceleration on your computer. Only some graphics drivers allow you to change the hardware acceleration. To change the hardware acceleration, take the following steps:

1. Right-click open space on the Desktop and choose Personalize from the context menu. Windows displays the Personalization window.

2. Click the Display Settings link. Windows displays the Display Settings dialog box.

3. Click the Advanced Settings button. Windows displays the Monitor and Graphics Card Properties dialog box. This dialog box s title bar shows the name of the monitor and the graphics card.

4.Click the Troubleshoot tab. Windows displays the Troubleshoot page.

5. If the Change Settings button is available in other words, if it s not grayed out, click the Change Settings button, and then authenticate yourself to User Account Control. Windows displays the Display Adapter Troubleshooter dialog box, as shown here.

6. Move the Hardware Acceleration slider one notch at a time from Full or wherever you find it toward None until the problems disappear. At each setting, click the Apply button, and check your computer to see what effect the change has had.

7. When the screen seems to be behaving as it should, click the OK button. Windows closes the Monitor and Graphics Card Properties dialog box, returning you to the Display Settings dialog box.

8. Click the OK button. Windows closes the Display Settings dialog box.

Setting Up and Using Multiple Monitors

Windows Vista lets you attach multiple monitors up to 10 to your computer to increase the amount of Desktop space available to you. This feature can make both work and play much easier - but it can also lead you to loading your desk with more monitors than it can comfortably provide a footing for. This discussion of using multiple monitors concerns only desktop computers to which you can add one or more extra graphics cards. But Windows also includes a feature called DualView that lets you use multiple monitors with portable computers and graphics cards with multiple outputs. Article 14 discusses this feature. If your graphics card supports two monitors, you should have no problem setting them up. Some graphics cards support two DVI monitors, while others can drive one DVI monitor and one VGA monitor. If in doubt about your graphics card s capabilities, consult its documentation or the manufacturer s website. To use multiple monitors on separate graphics cards, make sure that your graphics cards work together some graphics cards don t and that your computer s motherboard supports multiple monitors some motherboards don t. The monitors, by contrast, don t need to know about each other, as each gets its own input just as if it were the only monitor attached to the computer. So any monitor should work. You can mix CRTs and LCDs provided that each graphics card you use can handle the monitor to which it s connected. To set up multiple monitors, first get everything working to your satisfaction with one graphics card and one monitor or two, if the graphics card supports two. Then power down your computer and insert the new graphics card. You can install multiple graphics cards and monitors at a time, but unless you re very lucky and everything works, you ll be looking at some doubly confusing troubleshooting. Connect the second monitor, then power on everything. Don t be surprised if the boot-up display appears on the second monitor rather than your primary one. After you log on to Windows, it should discover the new hardware, which will trigger a Found New Hardware notification-area pop-up followed by the Found New Hardware Wizard. If Windows affects not to have noticed the new hardware, run the Add Hardware Wizard manually to add the graphics card and monitor. Next, open the Display Settings dialog box: right-click the desktop, choose Personalize, and then click the Display Settings link in the Personalization window. For each monitor you want to use, select the monitor and then select the Extend the Desktop onto This Monitor check box. Once you ve done that, let Windows know where the monitors are positioned in relation to each other by dragging the monitor icons into their relative positions. If you get confused as to which monitor is which, click the Identify Monitors button to have Windows flash up the number of each monitor on the monitor. Your primary monitor is the monitor on which Windows displays the Welcome screen. You can change the primary monitor by clicking the icon for the monitor you want to make primary and selecting the This Is My Main Monitor check box. Because only the primary monitor can perform full DirectX acceleration and run DirectX programs full screen, it s almost always best to make your primary monitor the one that s connected to your fastest graphics card. Set the screen resolution, color depth, and refresh rate for each monitor as usual see Article 3 for details. Once you close the Display Settings dialog box, you should have a substantially enlarged Desktop. By default, the Taskbar appears on your primary monitor, but you can drag it to any of the other monitors as you see fit. If the Taskbar is unlocked, right-click it and choose Lock the Taskbar from the context menu to unlock the Taskbar so that you can move it. Maximizing a window maximizes it for the monitor it s currently or mostly on. You can extend a normal window across two or more monitors by dragging its window border to the appropriate size. Doing so can occasionally be useful when you need to see a lot of information at the same time.

Check the Hardware Compatibility List before Trying to Install Multiple Monitors

Setting up multiple monitors can be a tricky and frustrating business. With some combinations of motherboards and graphics cards, you need to install the graphics cards in the right sequence in order to get them to work. Others work fine immediately. Others never work.

Before you try to implement multiple monitors, check the Hardware Compatibility List HCL at the Microsoft website, for details of the graphics cards that are known to work in multiple-monitor configurations with Windows.

Configuring Power Management

If you have a laptop computer and use it on the road, power management tends to be an important part of your computing life. You ve probably developed strategies to maximize your battery life while traveling, such as dimming the screen or slowing down the processor when you can accept poorer performance in the interests of longevity. Article 14 discusses the features that Windows offers for portable computers. If you have a desktop computer, power management tends to be less of a concern, because leaving your computer running usually isn t a problem. But to keep your computer healthy, to keep your or your employer s electrical bill to a minimum, and perhaps to contribute to keeping the polar icecaps in place, it s a good idea to configure power management on your computer. Windows offers a variety of power-management settings that let you closely manage your computer s power consumption. The following sections discuss these options. To configure power management, open the Power Options Properties window as follows:

1. Choose Start Control Panel. Windows displays a Control Panel window.

2. Click the Hardware and Sound link. Windows displays the Hardware and Sound window.

3. Click the Power Options link. Windows displays the Power Options window . The Power Options window contains different options depending on how your computer is configured. For example, the window for laptop computers includes options such as Choose What Closing the Lid Does and Adjust the Display Brightness, which don t appear for desktop computers. The following sections show samples of power options from different computers rather than from a single computer.

Choosing a Power Scheme

First, choose a power scheme and adjust it as necessary:

1. Open the Power Options window as discussed in the previous section.

2. In the Select a Power Plan area, select the option button for the power scheme you want to use: Balanced, Power Saver, or High Performance. Each of these schemes has preset settings for controlling whether and when the computer turns off the display, puts the computer to sleep, and adjusts the brightness of the display on a laptop computer.

3. To see what the settings for the plan are, or to change them, click the Change Plan Settings link under the option button for the power plan you ve chosen. Windows displays the Edit Plan Settings window .

4.In the Turn Off the Display drop-down list, set the delay in minutes or hours, or Never before Windows should turn off the display or monitor. For a laptop computer, you ll typically want to set a short delay while it s running on battery because the display typically uses more power than any other laptop component and a longer delay while it s plugged in.

5. In the Put the Computer to Sleep drop-down list, specify how long Windows should wait before putting the computer to sleep.

6. For a laptop, drag the Adjust Display Brightness sliders to specify how bright the

display should be while running on battery and while plugged in.

7. If you want to choose advanced power settings, click the Change Advanced Power Settings link, and then work as described in the section Choosing Advanced Power Options, later in this article. Otherwise, save the changes to the power scheme by clicking the Save Changes button. Windows closes the Edit Plan Settings window, returning you to the Power Options window.

Creating Your Own Power Plan

Windows three built-in power plans Balanced, Power Saver, and High Perrmance give plenty of flexibility for most people, especially if you customize these power plans to suit your needs. But you may want to create your own power plans to give yourself even more options.

To create a plan of your own, follow these steps:

1. In the Power Options window, click the Create a Power Plan link. Windows displays the Create a Power Plan window, as shown here.

2. Select the option button for the power plan on which you want to base your custom plan.

3. In the Plan Name text box, type the name you want to give your plan.

4. Click the Next button. Windows displays the Change Settings for the Plan window, as shown here.

5. Choose settings for turning off the display, putting the computer to sleep, and if appropriate, adjusting display brightness. For a laptop computer as in this example, choose settings for both running on battery power and running when plugged in.

6. Click the Create button. Windows creates the power plan and adds it to the Select a Power Plan list in the Power Options window. You can then use the power plan by selecting its option button.

To delete a custom power plan, click its Change Plan Settings link in the Power Options window. In the Edit Plan Settings window, click the Delete This Plan link, and then click the OK button in the Power Options dialog box that Windows displays for confirmation as shown here.

Choosing Power-Button, Lid, and Password-on-Wakeup Settings

Windows also lets you configure what happens when you press your computer s power button or buttons, whether Windows requires the user to enter a password after waking the computer up from sleep, and what happens when you close the lid of a laptop. To choose these settings, follow these steps:

1. In the left pane of the Power Options window, click either the Require a Password on Wakeup link or the Choose What the Power Button Does link. Windows displays the System Settings window .

If your computer has two or more power buttons, the second link is called Choose What the Power Buttons Do.

On a laptop, you can click the Choose What Closing the Lid Does link as well.

2.Use the When I Press the Power Button drop-down list or lists to specify what the computer should do when you press the power button: Do Nothing, Sleep, Hibernate, or Shut Down.

3. If the System Settings window contains a When I Press the Sleep Button drop-down list, use it to specify what the computer should do when you press the sleep button: Do Nothing, Sleep, or Hibernate.

4. For a laptop, use the When I Close the Lid drop-down lists to specify what the computer should do when you close the lid: Do Nothing, Sleep, Hibernate, or Shut Down.

5. If you want to change the settings in the Password Protection on Wakeup area, click the Change Settings That Are Currently Unavailable link, and then authenticate yourself to User Account Control. Windows makes the option buttons available. Select the Require a Password option button or the Don t Require a Password option button as appropriate.

6. Click the Save Changes button. Windows returns you to the Power Options window.

Choosing Advanced Power Options

The settings you ve seen so far let you configure the most important power options, but Windows also lets you set advanced options. To do so, follow these steps:

1. In the Power Options window, click the Change Plan Settings link for the power plan you want to affect. Windows displays the Edit Plan Settings window.

2. Click the Change Advanced Power Settings link. Windows displays the Power Options dialog box .

3.Choose settings see the description in the following sections. If a setting you want to change is unavailable, click the Change Settings That Are Currently Unavailable link, and then authenticate yourself to User Account Control.

4. If you want to choose settings for another power plan, select it in the drop-down list near the top of the dialog box, and then repeat step 3.

5. When you ve finished choosing settings, click the OK button. Windows closes the Power Options dialog box and returns you to the Edit Plan Settings window. If you need to reset the settings in the power plan to their defaults, click the Restore Plan Defaults button. The following sections discuss the advanced power options that you can set. Which of these options is available depends on your computer s configuration and capabilities.

Additional Settings

This category contains the Require a Password on Wakeup setting. You need to click the Change Settings That Are Currently Unavailable link and authenticate yourself to User Account Control before you can change this setting. Normally, you d set this setting in the System Settings window.

How to Approach the Purchase of Cheap Computers

The purchasing cheap computers is a task that takes a little time, but it can also save you money. Purchasing a desktop computer is a learning experience, but with a few tips, it can be money-saving experience.

In general, a standard or basic computer is highly useful and will give you all you ask for everyday use. It is perfect for surfing the Internet, using email, and even composing a report or doing bookkeeping. Basic computers can also download and play MP3 music and short videos. Limited photo editing is now also common on most new computers and many are really fine for playing most games.

A standard cheap computer is ideal for high school, college and university students, and also for most families, office workers, and even for small businesses.

If you re serious about games, you may need a special video card and additional computer Memory. You need to know what computer software programs (including games) you plan to set up, so that you can check the software box and make sure the computer you like will meet all requirements.

When you know the minimum requirements for your software, you will be prepared to go shopping. And when you re ready to shop, I recommend you first look online. Using the Internet is really the very best way to compare models, functionality, and compare prices.

You ll find that cheap computers are available in every season of the year, somewhere. You may visit some of the retail stores online to see if they have any live sales. Online shopping also allows you to visit some other retailers that sell computers online.

You will find that some online stores have current models and also "discontinued models" that are available at a big savings year round. Discontinued computers and laptops are simply the models from last season. They are as good as any current model, but they are no longer widely available. Discontinued desktop computers can be a huge bargain - but it is only worthwhile if it meets your minimum requirements.

As you can see, knowing ahead of time exactly your requirements means you can shop and immediately tell if any given computer is for you or not. Forearmed by knowing your minimum requirements makes it easy for you to grab the right computer at a very low cost, at the time it is available.

Be aware, a store may have 500 of a discontinued desktop computer or laptop computer, or they may have only 3. These 3 will likely sell very quickly, as their price is likely to be even lower because there are so few. It is best to be ready and take advantage of current discontinued models that are advertised online. In this way, the early bird catches the right computer at an especially good cost.

Using Dial-up Networking from Multiple Locations

If you travel with your portable computer, you ll probably want to create multiple locations for dial-up networking. Display the Phone and Modem Options dialog box by taking the following steps:

1. Choose Start Control Panel. Windows displays a Control Panel window.

2. In Control Panel Home view, click the Hardware and Sound link. Windows displays the Hardware and Sound window.

3. Click the Phone and Modem Options link. Windows displays the Phone and Modem Options dialog box.

Creating a New Location

To create a new location, take the following steps:

1. Click the New button on the Dialing Rules page of the Phone and Modem Options dialog box. Windows displays the New Location dialog box with the General page foremost .

2. Type the name for the location in the Location Name text box.

3. In the Country/Region drop-down list, specify the country or region in which you ll use this location.

4. Type the area code for the location in the Area Code text box.

5. In the Dialing Rules group box, specify access numbers for outside lines and carrier codes for long-distance calls and international calls as appropriate.

6. If you need to disable call waiting, select the To Disable Call Waiting, Dial check box and enter the appropriate code in the text box, either by typing or by selecting one of the standard codes from the drop-down list.

7.If the location uses pulse dialing, select the Pulse option button. The Tone option button is selected by default.

8. If necessary, create area code rules for dialing from the new location:

Click the Area Code Rules tab. Windows displays the Area Code Rules page.

Click the New button.

Type the area code in the Area Code text box.

In the Prefixes group box, select the Include All the Prefixes within This Area Code option button or the Include Only the Prefixes in the List Below option button as appropriate. If you choose the latter, click the Add button and use the resulting Add Prefix dialog box to specify the prefixes separated by spaces or commas.

In the Rules group box, select the Dial check box if these numbers require an extra number; if so, type it in the text box. Select the Include the Area Code check box if necessary.

Click the OK button. Windows closes the New Area Code Rule dialog box and enters the rule in the Area Code Rules group box on the Area Code Rules page.

9. If you need to use a credit card or other payment card to pay for the call from the location, specify it by following the steps below.

Click the Calling Card tab. Windows displays the Calling Card page of the New Location dialog box .

To use one of the card types listed in the Card Types list box, select its option button and enter the details in the Account Number text box and the Personal ID Number PIN text box.

To add a calling card, click the New button. Windows displays the New Calling Card dialog box. Enter the details of the calling card on the four tabs of this dialog box, then click the OK button. Windows adds the new calling card to the list in the Card Types list box on the Calling Card page of the New Location dialog box.

10. Click the OK button. Windows closes the New Location dialog box and adds the new location to the Phone and Modem Options dialog box.

Editing a Location

To edit a location, select it in the Locations list box on the Dialing Rules page of the Phone and Modem Options dialog box, and then click the Edit button. Windows displays the Edit Location dialog box, which is a renamed version of the New Location dialog box. Make the necessary changes, and then click the OK button. Windows closes the Edit Location dialog box and applies your changes to the location.

Using a Location

To use a location, select it in the Phone and Modem Options dialog box and click the OK button. Windows closes the Phone and Modem Options dialog box and uses the location you chose for calls you dial.

Using Windows Vista Home on a Portable Computer

This article discusses how to use the Windows Vista features that are mostly oriented to portable computers rather than desktop computers. You ll start by learning how to use Windows Mobility Center to access mobile-computing features, configure power-management settings for portable computers, and choose settings for Tablet PCs. After that, you ll find out how to choose settings for giving presentations on your laptop, how to connect an external monitor, how to create different locations to simplify dial-up networking in different places, and how to transfer and synchronize files between two computers.

Accessing Mobile Settings with Windows Mobility Center

Windows Mobility Center gives you quick access to a range of settings:

Display Brightness Click the icon to display the Edit Plan Settings window for your current power plan. Drag the slider to increase or decrease the brightness of the display.

Volume Click the icon to open the Sound dialog box. Select the Mute check box to mute the volume completely. Otherwise, drag the slider to set the volume.

Battery Status Click the icon to open the Power Options window. Use the status readout to see how much battery power remains. Use the drop-down list to switch from one of your current power plans to another.

Wireless Network Click the icon to launch the Connect to a Network Wizard, which you can use to connect to a network or to view your connection status. Use the status readout to see details of your current wireless network connection. Click the Turn Wireless Off button when you need to turn your wireless network adapter off. Click the resulting Turn Wireless On button to turn it back on.

External Display Click the icon to display the Display Settings dialog box. Use the status readout to check whether Windows has detected an external display. If you ve connected an external display, and Windows hasn t recognized it, click the Connect Display button to make Windows scan for the display.

Sync Center Click the icon or the Sync Settings button to open a Sync Center window, in which you can create and manage synchronization partnerships.

Presentation Settings Click the icon to display the Presentation Settings dialog box see the section Choosing Presentation Settings, later in this article. Click the Turn On button to turn on presentation mode; click the resulting Turn Off button to turn it off again. The easiest way to open Windows Mobility Center is to click the Power icon in the notification area and then click the Windows Mobility Center link in the pop-up window. You can also choose Start Control Panel, and then click the Adjust Commonly Used Mobility Settings link in the Control Panel window. To close button. Windows Mobility Center, click the Close button the

Using the Power-Management Features for Portable Computers

To get the best balance of performance and battery life from your portable, you ll probably need to configure its power settings carefully. In addition to the power-management features discussed in the previous article, Windows provides several power-management features for portable computers.

Using the Power Icon in the Notification Area

To work with power-management features on a portable computer, you use the Power icon in the notification area. Windows automatically displays this icon for a computer configured with a battery, so the icon should be there unless you ve chosen to hide it. The icon shows a battery on its own when the computer is running on battery power. It shows a battery with a power lead when the computer is plugged in and receiving power.

Adding the Power Icon to the Notification Area

If the Power icon doesn t appear in the notification area, you can add it as follows:

1. Right-click the Start button, and then choose Properties from the context menu. Windows displays the Taskbar and Start Menu Properties dialog box.

2. On the Notiﬁcation Area page, select the Power check box.

3. Click the OK button. Windows closes the dialog box and adds the icon to the notiﬁcation area. To see how much battery power you have left and whether the battery is charging, hover the mouse pointer over the Power icon to display a pop-up window, as shown here. To switch quickly from one power scheme to another, click the Power icon, and the select the appropriate option button in the pop-up window, as shown here. To open the Power Options window, click the Power icon in the notification area, and then choose More Power Options from the pop-up window. If you choose not to display the Power icon, choose Start Control Panel, click the Hardware and Sound link, and then click the Power Options link.

Choosing Power Settings for Running on Batteries

As you saw in the previous article, the Edit Plan Settings dialog box for a portable computer lets you choose different settings for when the computer is running on batteries and when it is plugged in. When you need to maximize battery life, set short delays for turning off the display and putting the computer to sleep. For example, if you work steadily at your computer, you might choose a delay of 2 minutes or 3 minutes for turning off the display and 5 minutes or 10 minutes for putting the computer to sleep. If you use your computer to work on documents that require pauses for thought, you may need to set a longer delay on turning off the display - having the screen black out when you re constructing a formula or a sentence can be very distracting.

Setting Battery Alarms, Notifications, and Actions

Sooner or preferably later, your battery will run out. To choose what Windows does when this happens, follow these steps:

1. In the Power Options window, click the Change Plan Settings link for the power plan you want to affect. Windows displays the Edit Plan Settings window for the plan.

2. Click the Change Advanced Power Settings link. Windows displays the Power Options dialog box.

3. Expand the Battery category so that you can see its settings

4. Expand the Critical Battery Action item, and then choose the action you want Windows to take when the battery reaches the critical level. You ll define this level in a minute. Your choices for when the computer is running on battery are Sleep, Hibernate, or Shut Down. When the computer is plugged in, you can also choose Do Nothing. Hibernate is usually the best choice, as it protects your data better than Sleep does. Shutting down the computer also protects your data, but it means that you ll need to perform a full startup when you plug in the computer rather than simply awaken it from hibernation.

5. Expand the Low Battery Level item, and then specify the percentage of battery power that Windows should treat as the low level. The default setting is 10 percent, which works well for many people.

6. Expand the Critical Battery Level item, and then specify the percentage of battery power that Windows should treat as the critical level - the point after which it s not safe to keep the computer running. The default setting is 5 percent, which should give enough battery life to ensure a successful hibernation or shutdown.

7. Expand the Low Battery Notification item, and then choose On or Off to control whether Windows warns you when the battery reaches its low level. Most people find the warning helpful, but you may prefer to work straight through to the critical level.

8.Expand the Low Battery Action item, and then choose the action you want Windows to take when the battery reaches the low level. Your choices are Do Nothing, Sleep, Hibernate, or Shut Down. Do Nothing is normally the most useful setting.

9. Click the OK button. Windows closes the Power Options dialog box and returns you to the Edit Plan Settings window.

10. Click the Save Changes button. Windows closes the Edit Plan Settings window and returns you to the Power Options window.

Troubleshooting: Recovering a Hung Laptop

If your laptop gets so thoroughly hung that it no longer responds to the power button, even when you hold the power button down for four or five seconds, you may need to disconnect the laptop from the AC wall socket and remove the battery in order to reset it. But before you do, make sure that you re not missing a hardware reset button on the laptop. Many laptops have these, but to prevent you from pressing them accidentally, they re usually located in a really awkward position. For example, on some computers, you need to poke the end of a paper clip or a similar thin, blunt instrument through a small hole in the bottom of the machine to press the reset button. If in doubt, consult the manual for your laptop before poking it in a sensitive area.

Configuring Tablet PC and Pen and Input Settings

If you have a Tablet PC one that accepts input via a stylus on its screen as well as via a keyboard and mouse, you can use the Tablet PC settings to control how the Tablet features work and the Pen and Input settings to configure how Windows reads pen input.

Configuring Tablet PC Settings

To configure Tablet PC settings, take the following steps:

1. Choose Start Control Panel. Windows displays a Control Panel window.

2. In Control Panel Home view, click the Hardware and Sound link. Windows displays the Hardware and Sound window.

3. Click the Tablet PC Settings link. Windows displays the Tablet PC Settings dialog box.

4. Choose Settings on the General page .

Handedness In this group box, select the Right-Handed option button if you re right-handed and the Left-Handed option button if you re left-handed. This setting controls where Windows displays the menus, so that they re not covered by the hand you re using.

Calibration Select the orientation in the Orientation drop-down list: Primary Landscape, Primary Portrait, Secondary Landscape, or Secondary Portrait. You can then click the Calibrate button and use the resulting wizard to calibrate the digitizer.

5.Choose settings on the Handwriting Recognition page :

Use the Personal Recognizer Select this check box to make Windows use personal handwriting recognition to improve its recognition of your handwriting. This feature is usually helpful.

Automatic Learning In this group box, select the Use Automatic Learning option button if you want the recognizer to store the words you use so that it can recognize them more easily in future. You get better results by using this feature at the expense of a minor security concern someone might be able to raid the recognizer and learn what you ve been writing. Select the Don t Use Automatic Learning, and Delete Any Previously Collected Data option button if you want to guard against this concern.

6.Choose settings on the Display page :

Orientation In this drop-down list, select the screen orientation you want to use: Primary Landscape, Secondary Portrait, Secondary Landscape, or Primary Portrait. The Preview area shows an icon representing the orientation.

Sequence To change the sequence in which Windows cycles through the orientations when you press a tablet button, click the Change button. Windows displays the Orientation Sequence Settings dialog box, as shown next. Use the four numbered drop-down lists to specify the sequence, and then click the OK button.

7. On the Other page, click the Go to Pen and Input Devices link if you want to open the Pen and Input Devices dialog box. Otherwise, click the OK button. Windows closes the Tablet PC Settings dialog box and applies your changes.

Aliquippa PA 15001 Onsite Computer Repair Service by MDofPC

Onsite Computer Repair Services include but are not limited to:

All service work carries a 30 day warranty from the date it was performed. All technicians are Microsoft and CompTia Certified with at least 5 years of experience.

Onsite Fee is $35 up to 30 miles away
Hourly service rate is $35 per hour

Call 412-680-1134 or email: mdofpc@gmail.com for more information

Ambridge PA 15003 $75 Computer Repair PickUp & Dropoff Service

We offer pickup and drop off computer repair service for personal and businesses at a flat rate price of just $75 for all labor & services, the only time you will pay more is if you need hardware or want to upgrade with no surprise costs or fees. We charge $35 to come out up to 30 miles from our location, we do make exceptions beyond 30 miles but an additional service fee applies depending on the additional mileage. And of course if you drop off there is no pickup or drop off fee.

When dropping off the computer for repair or service we have a 24 hours a day, 7 days a week pickup and drop off area open to the public. To drop your computer off, simply fill out an invoice and put a copy in the drop off box with the computer. The service will begin that day with an update following the next day via phone. Please try to provide details of what you would like to have done to expedite services. If your computer requires hardware or you want to upgrade we will call you and inform you of prices and options. When work is complete we will call you and you can arrange pickup or pay over the phone with a credit card and pickup anytime. If your computer was picked up you can choose to have it dropped off as part of the $35 pickup fee. If you dropped off your computer and would like to have it dropped off and setup the $35 fee would apply.

Your private data and personal information is of our highest importance, which is why we keep your data intact and your personal information secure. Our technician will ask you a few questions to make sure everything is the way you want it, giving you a wide variety of options. If your computer needs to be reloaded your data will be saved on a secure drive and restored afterwards. Also your personal information stays personal such as passwords, business documents, pictures and other related documents.

Pickup & Drop Off Computer Repair Services include but are not limited to:

Virus Detection & Removal, Spyware Detection & Removal, Windows Updates & Service Packs, Unlimited Antivirus Protection, Unlimited Spyware Protection, Registry Repair & Optimization, Removal of Unnecessary Programs, Free Up Additional Ram, Delete Internet History & Temporary Files, Defragment of Hard Drive, Provide Automatic Hard Drive Defrag, Troubleshoot & Install Printer Issues, Troubleshoot & Install Scanner Issues, Speed Up Internet Access, Upgrade Memory, Fix Broken Power Jacks, Replace Bad Power Supplies or Adapters, Dust & Debris Removal From PC, Upgrade & Replace Hard Drive, Troubleshoot & Replace Motherboard, Upgrade & Replace CD & DVD & BluRay Drives, Troubleshoot Network Issues, Upgrade or New Network Installations, Wireless Networking, Replace Cooling Fans, Replace & Fix Broken LCD Screens, Complete Laptop & Notebook Repairs, Data Restoration, Setup & Configure Backup and much more!

All service work carries a 30 day warranty from the date it was performed. All technicians are Microsoft and CompTia Certified with at least 5 years of experience.

Pickup & Drop Off Fee is $35 up to 30 miles away (covers both pickup & drop off)
Flat Service Rate of $75 plus any hardware or upgrades

We are the only computer repair location offering a Flat Service Repair Rate of $75 on all types of computers, laptops, servers, netbooks, mainframes and more.

Call 412-680-1134 or email: mdofpc@gmail.com for more information

Ambridge PA 15003 Onsite Computer Repair Service by MDofPC

Onsite Computer Repair Services include but are not limited to:

All service work carries a 30 day warranty from the date it was performed. All technicians are Microsoft and CompTia Certified with at least 5 years of experience.

Onsite Fee is $35 up to 30 miles away
Hourly service rate is $35 per hour

Call 412-680-1134 or email: mdofpc@gmail.com for more information

17 Inch Notebook

The following paragraphs summarize the work of Computer experts who are completely familiar with all the aspects of Computer. Heed their advice to avoid any Computer surprises.

I recently got a 17 inch notebook, and am quite impressed with its quality. It is so much better than the old IBM Thinkpad that I had years ago. Back then, laptop computers were big and bulky, the screen resolution was poor, they were even more expensive than now, and the batteries had very low life expectancy. But my new Dell 17 inch notebook is everything that my old laptop was not. It is sleek, low-profile, with hours of battery life, and a high-resolution lcd screen that is just simply a joy to look at.

Think about what you've read so far. Does it reinforce what you already know about Computer? Or was there something completely new? What about the remaining paragraphs?

I put off getting my new 17 inch notebook for quite a long time. I have always found the process of buying a new computer agonizing. No matter how long you wait, the very next week after you buy whatever system you have chosen to purchase, there is something cheaper and more powerful at a lower price and with a better warranty. It is enough to drive you completely batty. Nevertheless, I knew that the convenience of a new laptop computer was worth it, and eventually I broke down and bought my new 17 inch notebook. And I am sure glad that I did. There is nothing that beats a laptop computer.

The best thing about my 17 inch notebook is how easy it makes work on the go. With the prevalence of wifi coffee houses, I can work from my 17 inch notebook from all about town. I do a considerable amount of freelancing, so the luxury of being able to do all my work on the go, when I want, and from where I want, makes my life almost feel like a permanent vacation. And when I am done with my 17 inch notebook, I slip it into my laptop computer sleeve, and can carry it around me anywhere. It is no burden at all, because of its light weight, and though I occasionally worry about having it stolen, or accidentally damaged, so far no harm has come to my computer. My sturdy 17 inch notebook has really revolutionized my life. Of course, for many people, getting a new 17 inch notebook computer like I have done might be a bad idea. If you are not good at keeping track of your stuff, it is a definite no. You could easily lose your 17 inch notebook computer, along with all of your work and data, due to one careless mistake.

Allison Park PA 15101 $75 Computer Repair PickUp & Dropoff

Pickup & Drop Off Computer Repair Services include but are not limited to:

Virus Detection & Removal, Spyware Detection & Removal, Windows Updates & Service Packs, Unlimited Antivirus Protection, Unlimited Spyware Protection, Registry Repair & Optimization, Removal of Unnecessary Programs, Free Up Additional Ram, Delete Internet History & Temporary Files, Defragment of Hard Drive, Provide Automatic Hard Drive Defrag, Troubleshoot & Install Printer Issues, Troubleshoot & Install Scanner Issues, Speed Up Internet Access, Upgrade Memory, Fix Broken Power Jacks, Replace Bad Power Supplies or Adapters, Dust & Debris Removal From PC, Upgrade & Replace Hard Drive, Troubleshoot & Replace Motherboard, Upgrade & Replace CD & DVD & BluRay Drives, Troubleshoot Network Issues, Upgrade or New Network Installations, Wireless Networking, Replace Cooling Fans, Replace & Fix Broken LCD Screens, Complete Laptop & Notebook Repairs, Data Restoration, Setup & Configure Backup and much more!

All service work carries a 30 day warranty from the date it was performed. All technicians are Microsoft and CompTia Certified with at least 5 years of experience.

Pickup & Drop Off Fee is $35 up to 30 miles away (covers both pickup & drop off)
Flat Service Rate of $75 plus any hardware or upgrades

We are the only computer repair location offering a Flat Service Repair Rate of $75 on all types of computers, laptops, servers, netbooks, mainframes and more.

Call 412-680-1134 or email: mdofpc@gmail.com for more information

Aspinwall PA 15215 Onsite Computer Repair Service by MDofPC

Onsite Computer Repair Services include but are not limited to:

All service work carries a 30 day warranty from the date it was performed. All technicians are Microsoft and CompTia Certified with at least 5 years of experience.

Onsite Fee is $35 up to 30 miles away
Hourly service rate is $35 per hour

Call 412-680-1134 or email: mdofpc@gmail.com for more information

Aliquippa PA 15001 $75 Computer Repair PickUp & Dropoff Service

Pickup & Drop Off Computer Repair Services include but are not limited to:

Virus Detection & Removal, Spyware Detection & Removal, Windows Updates & Service Packs, Unlimited Antivirus Protection, Unlimited Spyware Protection, Registry Repair & Optimization, Removal of Unnecessary Programs, Free Up Additional Ram, Delete Internet History & Temporary Files, Defragment of Hard Drive, Provide Automatic Hard Drive Defrag, Troubleshoot & Install Printer Issues, Troubleshoot & Install Scanner Issues, Speed Up Internet Access, Upgrade Memory, Fix Broken Power Jacks, Replace Bad Power Supplies or Adapters, Dust & Debris Removal From PC, Upgrade & Replace Hard Drive, Troubleshoot & Replace Motherboard, Upgrade & Replace CD & DVD & BluRay Drives, Troubleshoot Network Issues, Upgrade or New Network Installations, Wireless Networking, Replace Cooling Fans, Replace & Fix Broken LCD Screens, Complete Laptop & Notebook Repairs, Data Restoration, Setup & Configure Backup and much more!

All service work carries a 30 day warranty from the date it was performed. All technicians are Microsoft and CompTia Certified with at least 5 years of experience.

Pickup & Drop Off Fee is $35 up to 30 miles away (covers both pickup & drop off)
Flat Service Rate of $75 plus any hardware or upgrades

We are the only computer repair location offering a Flat Service Repair Rate of $75 on all types of computers, laptops, servers, netbooks, mainframes and more.

Call 412-680-1134 or email: mdofpc@gmail.com for more information

What are Outline Fonts and Raster Fonts

Working with Fonts

Windows comes with a number of fonts that you can use to enhance your Windows display and your documents. You can add extra fonts as you need them, either by installing software that includes fonts such as Corel WordPerfect Office or Microsoft Office or by installing fonts directly. A font is the name given to a typeface. A typeface is a set of characters. Normally, the characters in a typeface have similar characteristics, so that they look as though they belong together, but this isn t an absolute requirement.

Understanding Outline Fonts and Raster Fonts

Windows supports two categories of fonts:

Outline fonts Outline fonts are the newest types of fonts. Windows renders outline fonts by using line and curve commands, which means that it can scale them to any size without distorting them and can rotate them. Windows supports three different types of outline fonts: TrueType fonts which Windows has used for many years, OpenType fonts a more recent extension of TrueType, and Type 1 fonts which are created by Adobe Systems for use with PostScript printers and devices. TrueType fonts use the .ttf extension, OpenType fonts use the .otf extension, and Type 1 fonts use the .pfm extensions.

Raster fonts Raster fonts are another older technology that Windows includes for backward compatibility. In a raster font, each character consists of a bitmap image that s displayed on the screen or printed on paper. Windows includes seven raster fonts: Courier, Modern, MS Sans Serif, MS Serif, Roman, Script, and Small Fonts. Like vector fonts, raster fonts use the .fonextension. Some of the TrueType fonts are organized into TrueType collections, which use the .ttc extension.

Displaying the Fonts Window

To work with fonts, display the Fonts window by taking the following steps:

1. Choose Start Control Panel. Windows displays a Control Panel window.

2. Click the Appearance and Personalization link. Windows displays an Appearance and Personalization window.

3. Click the Fonts link. Windows displays the Fonts window.

Rather than having an alphabetical list of fonts, you may want to group the fonts into their different types by using the Font Type column header .

Viewing and Printing a Font

To see what a font looks like, double-click its entry in the Fonts window. Windows displays the font in Font Viewer, which shows information on the font type, its file size, and copyright information, together with various sizes of the canonical sentence involving the quick brown fox and the lazy dog and the full set of numbers. To print the information displayed, click the Print button. Windows displays the Print dialog box. Choose the printer and any options, then click the Print button. Windows closes the Print dialog box and prints the information. To button. close Font Viewer, click the Close button the

Installing a Font

To install a font, take the following steps from the Fonts window:

1. Right-click blank space in the document area in the Fonts window, and then choose Install New Font from the context menu. Windows displays the Add Fonts dialog box with a font selected for installation.

2.Use the Drives drop-down list and the Folders list box to navigate to the drive and folder that contain the font you want to install. If necessary, click the Network button and use the Map Network Drive dialog box to map a network drive.

3. In the List of Fonts list box, select the font or fonts you want to install. You can click the Select All button to select all the fonts in the List of Fonts list box.

4. Make sure that the Copy Fonts to Fonts Folder check box at the bottom of the Add Fonts dialog box is selected. This option causes Windows to copy the fonts you re installing to the Fontsfolder, where you can manage them centrally. This is usually the best way to install fonts, especially when you re installing them from a removable medium such as a CD. But if the fonts you re installing are already located on your hard drive, and you don t want to make copies of them in the Fonts folder, you can clear this check box. Windows then creates a pointer to the folder that contains the font.

5. Click the Install button, and then authenticate yourself to User Account Control. Windows installs the font or fonts.

6. Click the Close button. Windows closes the Add Fonts dialog box, returning you to the Fonts window.

Getting More Fonts

Windows includes more than 300 fonts in a wide variety of styles, so you may not need to add any more fonts unless your documents have specific design needs.

If you do need more fonts, you can buy commercial font packages from most major software outlets and from many smaller vendors. But first, go to Microsoft s website and see if Microsoft is offering any fonts for free download. Then check out the free fonts that are available from many sites online: You may find a wide enough selection that you don t need to buy any fonts.

Deleting a Font

To delete a font, right-click it in the Fonts window, choose Delete from the context menu, and then authenticate yourself to User Account Control. Alternatively, select the font and press the Delete key. Windows displays the Delete File dialog box to confirm the deletion. Click the Yes button. Windows closes the dialog box and deletes the font.

Unloading Fonts instead of Deleting Them

If you load your Fonts folder with thousands of fonts, Windows runs more slowly. Loading a huge number of fonts increases the amount of memory Windows needs and generally slows down the speed with which it can handle other tasks.

So it s a good idea not to load too many fonts at a time. But you don t have to delete fonts that you temporarily don t want to load. Instead, you can move them to another folder and store them there until you need them again. At that point, move the fonts back to the Fonts folder, and you can use them again in your programs. If you work with many fonts, consider grouping them into a number of different folders so that you can quickly load the set of fonts you need for a particular type of document. If you work with a huge number of fonts, consider getting a font-management solution such as Extensis Suitcase.

The Bottom Line Understand printing terminology and how printing works in Windows A printer is the hardware device that prints documents. The printer driver is the software used to control the printer. A print job is an item sent to a printer for printing. To print, you typically issue a Print command from a program. The program tells Windows that it needs to print the document. The printer driver receives the information the program is sending and spools it to the printer, saving the information to disk and passing it along to the printer as fast as the printer can handle. Install a printer on your computer Installing a USB printer should be as simple as connecting it to AC power and to your computer. Windows detects the printer automatically and installs the driver for it. If no driver is available, you may need to visit Windows Update or provide a driver on disk. To install a parallel printer, run the Add Printer Wizard manually by clicking the Add a Printer button in the Printers window, and specify the printer make and model. Configure a printer s behavior to suit your needs To make a printer your default printer, right-click it in the Printers window, and then choose Set as Default Printer from the context menu. To configure other settings for a printer, right-click its entry in the Printers window, choose Properties from the context menu, and then work in the Properties dialog box. The General page of the Properties dialog box has some of the most important options: You can change the printer s name, add a location so that users know where it is, and add a comment explaining which printer this is and which print jobs it is for. The Advanced page of the Properties dialog box lets you limit the printer s availability - for example, to prevent users from printing during the night or at other inconvenient times. Print documents and manage print jobs The normal way to print a document is to open the document in the program that created the document, and then issue a Print command. You can also print in Explorer by dragging a document to the printer or a shortcut to the printer. To man- age your print jobs, double-click the printer in the Printers window, or double-click an icon for the printer in the notification area, and then work in the window for the print queue. Learn advanced printing techniques and print to a file If your computer isn t always connected to your printer, you can put the printer offline by right-clicking it in the Printers window and choosing Use Printer Offline. You can then send print jobs to the printer while offline and have them print when you reconnect to the printer. To print to a file, either select the Print to File check box in the Print dialog box, or set up a printer entry to always print to file. Another option is to print to an XML Paper Specification file, which you can distribute to other Windows Vista users.

View, install, and delete fonts To work with fonts, choose Start Control Panel, click the Appearance and Personalization link, and then click the Fonts link. The Fonts window displays the list of fonts installed on your computer. To install a font, right-click blank space in the document area in the Fonts window, choose Install New Font, and then use the Add Fonts dialog box to add the font. To remove a font, click it, and then press Delete. Instead of deleting a font, you can simply move it to another folder, so that you can restore it if you need it again.

Finding Out What Hardware and drivers You Can Use with Windows

This article discusses how to install hardware on your computer and how to install, update, and roll back device drivers - the software that makes hardware function. It covers concerns for particular types of hardware and also shows how to configure power management on your computer. Windows greatly simplifies the software end of the process of adding hardware. If the hardware is hot pluggable, Windows tries to locate and load the correct driver automatically. If Windows can t find a driver, you can use the Found New Hardware Wizard to provide the driver. If Windows can t find the hardware, you can use the Add Hardware Wizard to show Windows what the hardware is. Other articles discuss specific types of hardware. Article 12 discusses how to install, configure, and manage printers. Article 23 discusses how to install, configure, and use scanners and digital cameras. Article 25 discusses how to install, configure, and use games controllers.

Finding Out What Hardware You Can Use with Windows

To use computer hardware with Windows, you need the right driver - a piece of software that enables a hardware device and Windows to communicate with each other. Windows supports a wide range of hardware right out of the box and includes compatibility-tested drivers for many products. Windows can automatically download drivers for other devices, such as drivers that have been released since Windows itself was released. By using the Windows Update feature to keep your copy of Windows up to date, and by downloading new drivers from hardware manufacturers websites as necessary, you can also add the latest hardware to Windows. The devices you re more likely to have problems with are legacy devices more than a few years old, particularly those from smaller companies or from companies that have gone out of business. To check whether a hardware item is compatible with Windows, follow these steps:

1. Choose Start Help and Support. Windows opens a Help and Support window.

2. Click the Troubleshooting link. Help and Support displays the Troubleshooting in Windows screen.

3. In the Hardware and Drivers section, click the Windows Vista Upgrade Adviser link. Help and Support opens a browser window to the Windows Vista Upgrade Adviser page on the Microsoft website, where you can check whether your hardware is compatible with Windows Vista.

Using Hot-Pluggable Devices

Hardware devices that use USB, FireWire, and PC Card PCMCIA connections are usually hot pluggable - you can plug in and unplug the device while Windows is running without any adverse effects. Windows automatically loads and unloads drivers for hot-pluggable devices as needed. To install a hot-pluggable device for the first time, you must either be an Administrator or if you re a Standard user or a Guest user provide an Administrator password. Once Windows has successfully installed the driver for the device, any user can plug the device in and use it.

Installing a Hot-Pluggable Device

When you plug in a hot-pluggable device for the first time, Windows displays a pop-up from the notification area to let you know that it has noticed the device, as shown here.Windows then automatically looks for a driver to let Windows and the device communicate with each other. It first checks in its driver cache, which contains a wide variety of preinstalled drivers. If it doesn t find a driver there, and if your computer is connected to the Internet, it checks the Windows Update site for a driver for the device; if it finds a driver, it downloads it and installs it. If Windows is able to find a suitable driver in either the driver cache or Windows Update, it installs the driver, displaying a pop-up identifying the device as it does so, as in this example.

When the driver is installed and working, Windows displays a pop-up telling you that the hardware is ready to use, as shown here. If Windows can t find a driver for the device, it starts the Found New Hardware Wizard, so that you can supply the driver for the device manually. See the section Providing a Driver with the Found New Hardware Wizard, later in this article, for a walkthrough.

Removing a Hot-Pluggable Device

How you remove a hot-pluggable device depends on the type of device it is. Check to see whether Windows is displaying the Safely Remove Hardware icon a gray card with a green circle and white check mark with a green arrow above it in the notification area, as shown here in black and white, second from the left. If the Safely Remove Hardware icon appears, click it and see if the resulting context menu see the example displays an item for the device you re about to remove. If so, click that item.

PC Card devices always use the Safely Remove Hardware feature. Devices such as FireWire drives and USB memory-card readers typically have entries on the Safely Remove Hardware menu because Windows mounts them as drives, while items such as webcams and USB modems typically don t have entries. But check for an entry before removing a device. If there is an item for the device on the Safely Remove Hardware menu, it ll read Safely remove device, where device is the name by which Windows knows the device for example, Safely remove USBMass Storage Device DriveE:. Click this item and wait until Windows displays a popup telling you that it s safe to remove the device. Looking at the previous illustration, you can see a problem that you ll often encounter: If you have two or more USB mass storage devices attached, the only way to tell them apart is by drive letter. To get around this problem, follow these steps:

1. Either double-click the Safely Remove Hardware icon in the notification area or right-click it and then choose Safely Remove Hardware from the context menu. Windows displays the Safely Remove Hardware dialog box, as shown here.

2.Select the Display Device Components check box to make the dialog box display the details of each device, as shown here.

3. From the description, identify the device you want to remove, click it in the Hardware Devices list box, and then click the Stop button to stop it. Windows displays the Stop a Hardware Device dialog box, as shown here.

4. Verify that you ve selected the right device, and then click the OK button. Windows displays the Safe to Remove Hardware dialog box, as shown here.

5. Click the OK button. Windows closes the Safe to Remove Hardware dialog box. You can then remove the device.

6. Click the Close button. Windows closes the Safely Remove Hardware dialog box. If there s no entry for the device on the Safely Remove Hardware menu, or if the Safely Remove Hardware icon isn t displayed in the notification area make sure that it s really not there and that it s not just temporarily hidden, you don t need to use the Safely Remove Hardware feature to remove the device. Simply unplug it. Windows notices that you ve removed the device and unloads its driver.

Plugging a Hot-Pluggable Device in Again

When you plug a hot-pluggable device in again, Windows notices it and loads the driver without displaying any pop-up. At least, that s how it should work. In practice, Windows appears to have forgotten some hot-pluggable devices and decides to install them again.

Installing Devices that Are Not Hot Pluggable

Before installing a device that isn t hot pluggable, you must turn your computer off - and in most cases, disconnect the power cable and remove the battery if the computer has one. For example,to install a PCI card, you ll need to open the computer s case, insert the card in a PCI slot and screw in the retaining screw, connect any cables needed, and then close the computer s case again. When you restart your computer after installing the device, Windows normally detects the device during startup. If Windows can find a driver for the device, it loads the driver automatically and configures the device. If Windows can t find a driver, it launches the Found New Hardware Wizard.

Providing a Driver with the Found New Hardware Wizard

If Windows can t find a driver for a new device hot pluggable or not, the Found New Hardware Wizard displays its Windows Needs to Install Driver Software screen . This screen offers three choices:

Locate and Install Driver Software

Normally, you ll want to click this button to install the driver. You ll need to authenticate yourself to User Account Control to install the driver.

Ask Me Again Later Click this button to defer setting up the device until later. For example, if you realize you don t have the driver disc with you, you might click this button. Next time you log on, the Found New Hardware Wizard appears again. Don t Show This Message Again for This Device Click this button if you don t want to install the driver for the device and you don t want the Found New Hardware Wizard to prompt you again - for example, because no Windows Vista compatible driver is available yet. When you re ready to install the driver, you can do so as discussed in the next section. When you click the Locate and Install Driver Software button, the wizard disappears, leaving only a notification-area pop-up telling you that it is installing software. When the wizard finds that it has no driver for the device, it displays the Windows Couldn t Find Driver Software for Your Device screen . This screen offers you two choices: Check for a Solution Click this button if you want Windows to consult Microsoft s online database for the latest information about the device in case there s extra information that will help you install the device. Normally, the wizard simply displays the Windows Was Unable to Install Your Unknown Device screen, which suggests that you visit the website of the device s manufacturer to see if a driver is available there. You can click the Close button to close the wizard, or click the Back button in the upper-left corner of the window to return to the Windows Couldn t Find Driver Software for Your Device screen, where you can click the Browse My Computer for Driver Software button. Browse My Computer for Driver Software Click this button if you want to supply the driver from a CD or DVD, a floppy disk, or your hard disk or another connected disk. The wizard displays the Browse for Driver Software on Your Computer screen Click the Browse button, use the resulting Browse for Folder dialog box to select the folder that contains the driver, and then click the OK button. The wizard enters the path in the Search for Driver Software in this Location text box. You can also type the path in this text box, but normally it s easier to browse to the folder. Select the Include Subfolders check box if you want the wizard to search the folder s subfolders as well for the driver. Searching the subfolders as well is usually a good idea. Then click the Next button. The wizard searches for a suitable driver and, if it finds one, installs the device. If not, the wizard displays the Windows Was Unable to Install Your Unknown Device screen Click the Close button to close the wizard. Follow the instructions in the next section to install the device. If the wizard doesn t find a suitable driver, or if a file is missing, it displays the Windows Encountered a Problem Installing the Driver Software for Your Device screen . Click the Back button if you want to return to the Browse for Driver Software on Your Computer screen and try a different folder, or click the Close button if you want to close the wizard.

Specifying a Driver Manually

If the Found New Hardware Wizard can t find a suitable driver for a device, you may need to install the device manually. To do so, take the following steps. To show you examples of what you may see, the figures and illustrations show screens from installing various hardware devices rather than a single hardware device.

1. Press Windows Key+Break. Windows displays a System window.

2. In the Tasks panel on the left, click the Device Manager link, and then authenticate yourself to User Account Control. Windows displays a Device Manager window .

3.Find the device that needs the driver. Device Manager shows an exclamation point next to each device that s not working. For more detail on Device Manager, see the section Opening Device Manager, later in this article. If Windows doesn t know what the device is, look for an Unknown Device item in the Other Devices list. If it s not there, look in the appropriate category. For example, for a network card, look in the Network Adapters category.

4. Double-click the device s item. Device Manager displays the Properties dialog box for the device. The General page tells you that no driver is installed for the device.

5. Click the Driver tab. Device Manager displays the Driver page .

6.Click the Update Driver button. Device Manager launches the Update Driver Software wizard, which displays its How Do You Want to Search for Driver Software?

7. Click the Browse My Computer for Driver Software button. The wizard displays the Browse for Driver Software on Your Computer screen.

8.Click the Let Me Pick from a List of Device Drivers on My Computer button. Windows displays the Select Your Device s Type from the List Below screen .

9. In the Common Hardware Types list box, select the type of device you re installing - for example, select Bluetooth Radios for a Bluetooth device, Display Adapters for a graphics card, or Monitors for an extra monitor.

Some of the categories are cryptic - for example, Multifunction Adapters or Portable Devices.

If you can t find a suitable category, select the Show All Devices item.

10. Click the Next button. The wizard displays the Select the Device Driver You Want to Install for This Hardware screen . If you selected the Show All Devices item on the previous screen, it may take Windows a minute or two to assemble the list of drivers.

Searching for Driver Software from the Browse for Driver Software on Your Computer Screen

If you ve downloaded a driver that wasn t available when you first tried to install a device, use the Browse button on the Browse for Driver Software on Your Computer screen of the Update Driver Software Wizard to select the folder that contains the driver. Then click the Next button to make the wizard search that folder for the driver. You don t need to go through the process of picking the driver from a list.

11.If Windows has a driver for the device, you can select it by clicking the manufacturer in the Manufacturer list box and the device in the Model list box. But usually the Found New Hardware Wizard will have identified the driver if Windows has it already, so you ll be visiting this page of the wizard only if you need to install a driver that Windows doesn t have. Click the Have Disk button. Windows displays the Install from Disk dialog box, shown here.

12. If you have the driver on a floppy disk or a CD or DVD, insert it in the appropriate drive and select the drive in the Copy Manufacturer s Files From drop-down list. If you have the driver on a local drive or network drive, click the Browse button, use the resulting Locate File dialog box a common Open dialog box to locate the driver file, and then click the Open button to enter its name and path in the Copy Manufacturer s Files From text box.

13 Click the OK button. The wizard displays the Select the Device Driver You Want to Install for This Hardware screen with the name of the hardware model or models identified by the driver.

14.Select the proper driver if there are two or more models, and then click the Next button.

15. If Windows doesn t think the driver is correct for the device, it displays the Update Driver Warning dialog box shown next, warning you that the hardware may not work and that your computer might become unstable or stop working. Click the Yes button if you re sure you want to install this driver. Otherwise, click the No button, and then select another driver.

16. If the driver doesn t have a valid digital signature, or if Windows can detect another obvious problem with it, the wizard displays a Windows Security dialog box such as the one shown next which has been expanded to show its details. Click the Install This Driver Software Anyway button only if you re sure that the source of the driver is trustworthy. Otherwise, click the Don t Install This Driver Software button, and then look for a signed driver for example, on the manufacturer s website.

17.If the wizard finds no problem with the driver, it installs the driver and displays the Windows Has Successfully Updated Your Driver Software screen .

18. Click the Close button. The wizard closes, returning you to the Properties dialog box for the device.

You May Sometimes Need to Install Unsigned Drivers

Ideally, every driver you install will be signed by its publisher so that you can be sure of its provenance. In practice, however, you may need to install unsigned drivers to get older hardware working with Windows Vista, especially when the device s manufacturer has gone out of business or been taken over by another company.

If a driver installation makes your computer unstable, use System Restore see Article 16 to restore Windows to its state before you installed the driver.

What Happens if You Choose the Wrong File

If the wizard can t find hardware information in the location you specified, it displays the Select Device message box telling you that the location you specified doesn t contain information about your hardware. The wizard then displays the Install from Disk dialog box again so that you can specify a different location for the file.

If you chose the wrong file, you can now choose the right one. But if the file doesn t work, you re probably stuck. You can click the Cancel button to close the Install from Disk dialog box and return to the Select the Device Driver You Want to Install for This Hardware page so that you can select a built-in driver, but that s about it. Click the Cancel button to cancel the wizard.

19.Click the Close button. Windows closes the Properties dialog box, returning you to Device Manager.

20. button. Windows closes Device Manager. Choose File Exit or click the Close button the

If there s a problem with the driver file you supply, the wizard may display the Windows Encountered a Problem Installing the Driver Software for Your Device screen . From here, you can click the Back button to return to the Select Your Device s Type from the List Below screen of the wizard or click the Close button to close the wizard and give up on installing the device for now.

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Chipsets - part 8

Intel 925X PCI Express chipset

In the summer of 2004 Intel introduced a new family of chipsets that they claimed brought the most profound changes in PC platform architecture in more than a decade. The relative positioning of the chipsets - codenamed Alderwood and Grantsdale - is similar to that of the Canterwood and Springdale chipsets which preceded it. The 925X PCI Express chipset is the higher-end of the two, boasting a number of specific performance enhancements and being designed to deliver the ultimate gaming experience when coupled with Pentium 4 Extreme Edition CPUs.

The new chipsets are designed for use with the latest Prescott-cored Pentium 4 CPUs, designated by the new numeric model naming scheme - initially the 560 at 3.6GHz, down to the 520 at 2.8GHz. They will therefore only be used in motherboards that support Intel's innovative LGA775 package, which facilitates a direct electrical connection between the chip module substrate and the motherboard which the company claims will provide the robust power and signal delivery needed for future performance headroom.

All the new chipsets support Hyper-Threading, an 800MHz FSB and dual-channel DDR2-533 memory and enable a broad spectrum of new platform capabilities:

Intel High Definition Audio enables multistreaming, 7.1 surround sound and dynamic jack retasking in a groundbreaking PC audio solution that provides performance comparable to high-end consumer electronics (CE) equipment.
Intel Matrix Storage Technology provides the performance benefits of RAID 0 for media-intensive applications and the added protection of RAID 1 for critical digital media files and data on just two drives.
The I/O Controller Hub 6 (ICH6R version) supports four 1.5 GBps Serial ATA (SATA) ports with Advanced Host Controller Interface (AHCI) capability, enabling Native Command Queuing for enhanced storage performance.
Four PCI Express x1 high-speed expansion ports are ready for Gigabit Ethernet and future applications, including multiple TV tuners implemented in a single card.
Intel Wireless Connect Technology enables users to create or expand a wireless network without external access point hardware. Intel Wireless Connect Technology requires a specific Intel 9XX Express Chipset and a separate Intel wireless LAN solution to operate.

Intel's new Flex memory system introduces some welcome flexibility, with dual-channel operation no longer being restricted to identical memory modules bought in matched pairs. Now the requirement is simply for the same amount of memory - whatever the configuration - in each of the two available banks.

Foremost amongst the innovations is the introduction of the PCI Express (PCX) bus technology. As digital video content becomes ever more important in today's electronic universe, no single aspect of the personal computing platform requires as much performance increase as the graphics interface.

The new chipsets address this need in the shape of the revolutionary 16x PCI Express graphics interface, as its name implies, an aggregation of 16 lanes. This provides the increased bandwidth and scalability necessary to tackle the most demanding multimedia tasks, with up to four times the theoretical maximum bandwidth over previous generation AGP8X-based solutions - up to 4 GBps of peak bandwidth per direction and up to 8 GBps concurrent bandwidth.

AGP is unceremoniously consigned to history, the new chipsets providing no AGP interface at all. In time 1x PCX will replace the decade-old PCI standard.

How to install software on your Windows Mobile or Pocket Pc PDA

Before we begin, it's important to understand that there are two types of Pocket PC installation files: (1) those which must be run and installed from your Windows PC (usually .EXE files), and (2) those which must be transferred to your Pocket PC before they can be installed (usually .CAB files).

For installation instructions, select which type of file you have to install:

Install from your Computer

Install from your pocket pc

Most Windows Mobile software is installed to your Pocket PC through ActiveSync, the synchronization utility installed on your Windows PC. Using your computer, download the software you wish to install to your Pocket PC. We recommend downloading to your Windows Desktop so you'll be able to find the file later:

Run the installation file on your PC by double-clicking it on your Windows Desktop. This should be done while your Pocket PC is synced.

The installation program will install files to your computer's hard drive, then establish a link with your Pocket PC, copying the needed files to your handheld's onboard memory:

If you have a Windows Mobile 5 handheld, you'll see a pop-up on the Pocket PC's screen to confirm the installation. Tap "Yes." If you have a flash memory card installed, a second screen will also appear allowing you to choose the installation destination, internal memory or flash card. Make your choice and tap Install. Allow the process to complete:

The program is now installed. A soft reset may be required for some software installations. To run the program, locate it in your Programs menu by tapping Start > Programs.

Some Pocket PC / Windows Mobile software requires that it be installed directly from the Pocket PC. These software setup titles are usually distributed as .CAB files.

The first step is to move the .CAB installation file you downloaded to the Pocket PC. First, sync your Pocket PC with your Windows PC. After synchronization, select the Explore feature from ActiveSync's main screen.

The Explore feature allows you to browse your Pocket PC's internal storage like you would browse your computer's hard drive(s) in My Computer or Windows Explorer. Once the Mobile Device explorer window is open, go to your Windows Desktop, or wherever the file you want to move to the Pocket PC is stored. Right-click it. When the menu drops down, select Copy. Return to the Mobile Device explorer window, right-click somewhere in the window, and select Paste:

The .CAB file will be moved to the Pocket PC. Allow this process to complete. Remove your Pocket PC from its cradle or disconnect it from its sync cable. On your Pocket PC, go to File Explorer in the Program folder on the Start Menu.

Find the file you moved in File Explorer. When you find it, double-click it. It will install itself on your Pocket PC and add itself to the Start Menu or the Programs folder.

You're done. The program will now appear in the Programs folder:

Once the software has been installed, feel free to delete the .CAB file from your Pocket PC's memory if you wish.

Cheap Computers

The following article covers a topic that has recently moved to center stage--at least it seems that way. If you've been thinking you need to know more about it, here's your opportunity.

What kind of computer do you use? I personally enjoy a Mac Ibook G4. This baby does everything I want it to and more. It's great the way they make them so compact and they weigh less than five pounds. Technology is a dream these days, and it's only getting better. You can literally buy a notebook computer that's a mere half inch thick, but yet still packs a high level of gigabytes. It's truly amazing. As you know by now, folks around the globe enjoy the benefits of computers in their very own homes. In fact, if you still don't have a PC or Mac, then you're probably slightly out of the loop. Well folks, now days you don't have to grapple with gargantuan computer costs. There is a vast spectrum of cheap computers to choose from. What are you looking for?

Think about what you've read so far. Does it reinforce what you already know about Computers? Or was there something completely new? What about the remaining paragraphs?

When it comes to our home computers, many of us would have difficulty getting along without them. There are just so many conveniences that come from Internet access. The World-Wide-Web grants us the ability to do our taxes without paper, handle our bank accounts from home, and order groceries and have them delivered. Wow, now that's ideal. The great thing now days is the fact that computer prices have come down significantly. It's feasible to purchase cheap computers and not miss out on the finer features. I can remember just back in 98 when I purchased a massive Gateway desktop computer, and paid like 1600 bucks for it. What a rip-off! These days we would all laugh at such a price tag on such a mediocre PC. I mean it didn't really have anything great or exclusive. A 15 inch monitor, tower, keyboard, mouse, and 13 gigs aren't saying much. Heck, I only gave a grand for my Apple notebook that has loads more features and 60 gigabytes of memory. Man, did things change. Thank God for cheap computers! Therefore, if you're new to home computers, then I would suggest getting online. Although superstores such as Best Buy and Circuit City are great for browsing, I still think the best deals are found in cyberspace. Now, I realize that you may not have a computer in order to browse for cheap computers, but one of your buddies or family members surely does. Get on Google.com and search for the lowest prices on PCs. Dell is one of the finer companies that offer specials on package deals. You can get the entire setup for around 300 bucks. Now that's a lot better than 1600. Yes indeed, the net is loaded with cheap computers now days.

You can't predict when knowing something extra about Computers will come in handy. If you learned anything new about &keyword% in this article, you should file the article where you can find it again.

Desktop Computer

When you're learning about something new, it's easy to feel overwhelmed by the sheer amount of relevant information available. This informative article should help you focus on the central points.

I am of the first generation that literally grew up with desktop computers; I remember having them in our third and fourth grade classrooms. We had the Apple IIE back then, which ran on huge floppy disks which ground away in the disk drive when we inserted them wrong. They were useful though; besides Number Munchers and Oregon Trail they taught us how to type quickly and manage to find our way around the basic operating systems. Though my parents were leery of computer technology my generation jumped into it, never afraid to go digging around inside an operating system to find what we needed.

My family got our first desktop computer when I was in middle school, and though it wasn t much more advanced than the Apple IIE it was enough for me to keep myself occupied; I used it for typing up essays and playing a few games. We were ushered into the world wide web when I was in high school, and by the time I was in college just about everyone had a desktop computer of their own.

Once you begin to move beyond basic background information, you begin to realize that there's more to Computers than you may have first thought.

Now it s tough to imagine myself without a computer, as I use it literally every day (I m even using it to type this article). Though the internet I m able to access just about any sort of information I need. I type all of my documents on my computer, and I usually check my email a few times every day. My desktop computer also has a DVD drive, and since I don t own a television I watch quite a few movies from my couch, which I keep in easy view of my desktop.

Entry-level desktop computers used to start at around $1000, but now you can get a basic computer for just a few hundred dollars which can do just about everything the higher-end computers can do besides handle some intensive games and graphics programs. You can get a computer tower for even less if you already have a monitor and printer. If you don t have a desktop computer already it s high time you break down and get one, especially considering how cheap desktop computers have become. Though laptops are still relatively expensive, a low-end desktop allows you to surf the internet, type up letters and documents, manage your money, play (most) computer games, and even serve as a home media center. It s probably one of the best investments you can make, since it s something you ll use every single day.

Is there really any information about Computers that is nonessential? We all see things from different angles, so something relatively insignificant to one may be crucial to another.

Toshiba Satellite Notebook

The more you understand about any subject, the more interesting it becomes. As you read this article you'll find that the subject of Computers is certainly no exception.

I ve been very happy with my Toshiba Satellite notebook. I ve been using Toshiba Satellite s now for a number of years and have never had any problems with any of them. Today I m using the Toshiba Satellite M35-S320, which came out a couple of years ago. It s already completely obsolete of course, and I d be surprised if you could still find it for sale new in any actual store. Of course, you can still order it online for about a grand.

My Toshiba Satellite notebook may be more or less obsolete now, but it s still a great laptop and meets all of my needs. Obsolete in the computer world doesn t mean useless, it just means that there are a lot of newer models available. My M-35 has a 60GB hard drive, 512MB of RAM memory, and a Pentium-M 1.5 Ghz processor. It also comes with a combined DVD-ROM/CD-RW unit, a 32MB NVIDIA Geforce FX Go5200 graphics card, a 15.4 inch TFT screen, and of course a wireless modem and network card. These are still pretty decent specifications for a laptop notebook today.

The Toshiba Satellite notebook is so named because of its wireless network ability. When the first Toshiba Satellites came out, this was something of a novelty, and was considered state of the art. Now, of course, most laptops you buy have built in wireless networking ability. Still, the Toshiba Satellite ranks amongst the most populary used notebooks for on the go internet access. They are all able to go online right out of the box, so long as you have an accessible network nearby.

It's really a good idea to probe a little deeper into the subject of Computers. What you learn may give you the confidence you need to venture into new areas.

Toshiba Satellite notebooks are also good for handling fairly robust entertainment features, such as movies and computer games. Because they usually have good graphics cards, fast processors and plenty of RAM memory, they are able to handle even most current games and can play movies with excellent visual quality. In fact, one of my most frequent uses for my Toshiba Satellite notebook has been as a game platform and as a way to watch movies in remote areas, such as the jungle of cubicles I used to work in.

Motherboards - part 1

MOTHERBOARDS

The motherboard is the main circuit board inside the PC which holds the processor, memory and expansion slots and connects directly or indirectly to every part of the PC. It's made up of a chipset (known as the "glue logic"), some code in ROM and the various interconnections or buses. PC designs today use many different buses to link their various components. Wide, high-speed buses are difficult and expensive to produce: the signals travel at such a rate that even distances of just a few centimetres cause timing problems, while the metal tracks on the circuit board act as miniature radio antennae, transmitting electromagnetic noise that introduces interference with signals elsewhere in the system. For these reasons, PC design engineers try to keep the fastest buses confined to the smallest area of the motherboard and use slower, more robust buses, for other parts.

This section focuses on basic functionality and layout - the motherboard's various interfaces, buses and chipsets being covered elsewhere.

Evolution

The original PC had a minimum of integrated devices, just ports for a keyboard and a cassette deck (for storage). Everything else, including a display adapter and floppy or hard disk controllers, were add-in components, connected via expansion slots.

Over time, more devices have been integrated into the motherboard. It's a slow trend though, as I/O ports and disk controllers were often mounted on expansion cards as recently as 1995. Other components - typically graphics, networking, SCSI and sound - usually remain separate. Many manufacturers have experimented with different levels of integration, building in some or even all of these components. However, there are drawbacks. It's harder to upgrade the specification if integrated components can't be removed, and highly integrated motherboards often require non-standard cases. Furthermore, replacing a single faulty component may mean buying an entire new motherboard.

Consequently, those parts of the system whose specification changes fastest - RAM, CPU and graphics - tend to remain in sockets or slots for easy replacement. Similarly, parts that not all users need, such as networking or SCSI, are usually left out of the base specification to keep costs down.

The basic changes in motherboard form factors over the years are covered later in this section - the diagrams below provide a detailed look at the various components on two motherboards. The first a Baby AT design, sporting the ubiquitous Socket 7 processor connector, circa 1995. The second is an ATX design, with a Pentium II Slot 1 type processor connector, typical of motherboards on the market in late 1998.

Motherboard development consists largely of isolating performance-critical components from slower ones. As higher speed devices become available, they are linked by faster buses - and the lower-speed buses are relegated to supporting roles. In the late 1990s there was also trend towards putting peripherals designed as integrated chips directly onto the motherboard. Initially this was confined to audio and video chips - obviating the need for separate sound or graphics adapter cards - but in time the peripherals integrated in this way became more diverse and included items such as SCSI, LAN and even RAID controllers. While there are cost benefits to this approach the biggest downside is the restriction of future upgrade options.

Chipsets - part 7

Intel 865 chipset

If the i875 chipset can be viewed as the logical successor to i850E, then its mainstream variant, the i865 chipset - formerly codenamed Springdale - can be viewed as the logical successor to the i845 series of chipsets. Not only do the i875/i865 chipsets represent a huge technological leap compared to their predecessors, but the performance gap between the pair of recent chipsets is significantly less than it was between the i850E and i845 family.

There is a clear trend in PC hardware towards parallel processes, epitomised by Intel's Hyper-Threading technology. However, there are other examples of where performing several tasks at the same time is preferable to carrying out a single task quickly. Hence the increasing popularity of small RAID arrays and now the trend towards dual-channel memory subsystems.

Currently, there are two different strategies being employed in dual-channel memory controllers, one in which where each memory bank has its own memory channel and an arbiter distributes the load between them and the other to actually create a wider memory channel, thereby "doubling up" on standard DDR's 64-bit data paths. In common with the i875P chipset, the i865's Memory Controller Hub employs the latter, the same conditions for dual-channel operation also applying.

The i865 memory controller is the same as that used by the i875P chipset, supporting:

Hyper Threading
Dual 64-bit DDR memory channels
Communication Streaming Architecture bus for gigabit Ethernet

and capable of being paired with either the ICH5 or ICH5R chip - which handles things like the 10/100 Ethernet interface, 6-channel AC97 audio interface, USB 2.0, the PCI bus, etc., to provide the following additional features:

8 USB 2.0 ports
Dual independent Serial ATA ports

The ICH5R also provides software RAID for Serial ATA drives.

The upshot is that - unlike the i875P - i865 chipsets are available in three different versions:

i865P: supports DDR266 and DDR333 memory only and doesn't support the 800MHz FSB.
i865PE: as per i865P, plus 800MHz FSB and DDR400 memory support.
i865G: as per i865PE, plus Intel's integrated graphics core.

While the i865G's graphics core is the same as was featured on the i845G chipset, its performance will be faster, due both to a faster memory subsystem and a higher working frequency of the graphics core itself.

The following table compares a number of major characteristics of the i865P chipset with a selection of Intel's other recent Hyper-Threading chipset offerings:

	i865PE	i875P	E7205	i845PE	i850E
Processor	Pentium 4	Pentium 4	Pentium 4	Pentium 4 Celeron	Pentium 4 Celeron
System Bus (MHz)	800/533/400	800/533/400	533/400	533/400	533/400
Memory Modules	4 DIMMs	4 DIMMs	4 DIMMs	2 double-sided DDR DIMMs	4 RIMMs
Memory Type	Dual-Channel DDR 400/333/266 SDRAM	Dual-Channel DDR 400/333/266 SDRAM	unbuffered only x72 or x64 DIMMs DDR SDRAM	DDR 333/266	PC1066 PC800-40 PC800-45 RDRAM
FSB/Memory Configurations	800/400 800/333 533/333 533/266 400/333 400/266	800/400 800/333 533/333 533/266	533/266 400/200	533/333 533/266 400/266	533/PC1066 533/PC800-40 400/PC800-45 400/PC800-40
Peak Memory Bandwidth	6.4GBps	6.4GBps	4.2GBps	2.7GBps	4.2GBps
Error Correction	N/A	ECC	ECC	N/A	ECC/Non-ECC
Graphics Interface	AGP 8x	AGP 8x	AGP 8x	AGP 4x	AGP 4x
Serial ATA	2 ports ATA 150	2 ports ATA 150	N/A	N/A	N/A
USB	8 ports Hi-Speed USB 2.0	8 ports Hi-Speed USB 2.0	6 ports Hi-Speed USB 2.0	6 ports Hi-Speed USB 2.0	4 ports USB 1.1

Computers For Sale

Imagine the next time you join a discussion about Computers For Sale. When you start sharing the fascinating Computers For Sale facts below, your friends will be absolutely amazed.

Do you have a computer yet? No, I'm not talking about that Tandy 1000 you've got tucked away in the spare room. I'm talking about a new computer. You know, one that has Internet access capabilities. Okay, I'm probably going a tad too far with that spiel, but you do want to make sure your PC or Mac is up to par. This is the only way you can enjoy the latest technology. Therefore, it's time to browse the vast array of computers for sale. There is virtually no limit to what you can buy. Personal computers can do it all these days. Looking to burn CDs? No problem. Want to have high speed cable Internet access? Sure thing. Today's machines can do it all and they're more compact than ever before.

So far, we've uncovered some interesting facts about Computers For Sale. You may decide that the following information is even more interesting.

Do you know where to browse in search of computers for sale? This really isn't a hard question. In fact, you probably have a few places near by. Circuit City is a wonderful place to begin shopping for PCs. The first thing you want to determine is what you want your personal computer to do. If you're in search of the basics such as Internet access, typing papers, and sending emails, then you won't have to spend much. Now days you can pick up a Dell desktop package for around 300 bucks. That will include the tower, monitor, keyboard, and sometimes a free printer. Everything you need to get started. Best Buy is another great place to shop for computers for sale. They have a large selection ranging from Sony to IBM. Are you dreaming of a simple desktop PC or do you have your heart set on a mini notebook. They make these as small as a half an inch thick these days. But don't worry; they still pretty much do it all. Now you can even download your own tunes to the computer, and then burn them to a CD. This is perfect for those of us who want to spend less on music.

Have you browsed the plethora of computers for sale online? The World-Wide-Web has the absolute biggest selection of PCs to choose from. Basically anything you could possibly be searching for that's related to computers is online. When you sort through the computers for sale online, you also ensure yourself of acquiring the best deals on hardware and software. Isn't it time you took a gander at the current PC and Mac selection, folks? When it comes to personal computers, things are changing every day. Don't get left behind.

That's the latest from the Computers For Sale authorities. Once you're familiar with these ideas, you'll be ready to move to the next level.

Apple Desktop Computers

The following paragraphs summarize the work of Computers experts who are completely familiar with all the aspects of Computers. Heed their advice to avoid any Computers surprises.

Are you old enough to remember the days before computers? If you are, then you know that back then, a typewriter was just a typewriter. Then IBM came out with the one with the ball. You could do something no ordinary person thought was possible-change the font.

The personal computer changed everything particularly in the way we created documents. Now the rest is history with some many applications, games; how can anyone live without a computer? The problem is that we have been brainwashed and our senses dull to into thinking there is only one type of computer. Not true.

Like you probably have, I have been tied, eye and hands, to a computer for about ten years and I too thought that all computers were created equal until I started using an Apple desktop computer or Mac.

Now that we've covered those aspects of Computers, let's turn to some of the other factors that need to be considered.

An Apple desktop computer is about the same as an ordinary computer as a horse is to a cow. The cow runs, well, like a cow. The horse (and the Apple desktop computer) is sleek and efficient, build for performance. The cow will do what you want it to with a little encouragement. The apple desktop computer lives to follow your commands just like the horse. The cow needs to rest and often quits working 'just because'. The Mac works on and on and on because that is what it is made to do.

You might think that I am just saying this but in fact, I became a true believer after a month with my Apple desktop and suddenly realized, it had never crashed even once. The 'cow' crashes about twice a day.
Sure, if you worked with a PC for a long time, you need a period of adjustment. Not that the Apple computer is difficult; it is just slightly different. To open a file from the "finder" known on a PC as the explorer, you can't press 'return' that take some getting use to. And here is another thing that is different with an Apple desktop. No viruses. I do not even own a virus cleaning system although I keep a virus checker going in the background on my Apple desktop computer. And what do you think it finds? PC viruses that have no effect on my Mac.

Another thing about an Apple computer that is great is the automatic software updates from the Internet. Just hook up to the Net and it automatically calls home for updates. No checking the website, no figuring out what you need. The operating and installed apple software is updated automatically.

I tell my friends, my Apple desktop computer is a real computer; the "other one" is just a toy in comparison.

Now might be a good time to write down the main points covered above. The act of putting it down on paper will help you remember what's important about Computers.

Handheld devices

Handheld computing devices, or personal data assistants (PDAs), are rapidly growing in popularity. Along with the growing use of PDAs has come a corresponding growth in the demand for wireless network connectivity, auditing, and management. Consider the advantages of being able to check your email anywhere in your house or office with only a few taps of a stylus and no boot-up time.

Many companies are already developing high-end productivity applications for the PDA market. For example, the Pocket PC (which uses Microsoft's embedded operating system, Windows CE) ships with a Microsoft Terminal Server Client, allowing you to connect to servers virtually anywhere on your network. Medical students are even using PDAs connected to wireless networks to watch surgeries via streaming video. Thus, the potential for growth in this market is tremendous.

Traditionally, the two main competitors in the PDA operating system market have been Palm (using Palm OS) and the Pocket PC (using Windows CE). However, the use of Palm OS has gradually faded away into obsolescence, and has been replaced by Windows CE. Let us then finally exorcise the melancholy specter of Palm from this book and return to it no more.

At the time of this writing, the Palm has not shown much in the way of 802.11b connectivity, but the Pocket PC, on the other hand, has shown tremendous abilities. Many manufacturers are writing Pocket PC drivers for their hardware, thus expand-ing the capabilities of this already very functional product. Just as with desktop or laptop computers, there are many models of hardware that will support and run the Pocket PC operating system. Each device is unique and offers its own features and benefits. Features such as increased memory, higher resolution screens, and the capability to work with external hardware such as PCMCIA and compact flash cards are all factors to consider in your purchasing decision.

One device that we have found more than equal to the task is the Compaq iPAQ. When it comes to wireless connectivity and features, iPAQ is the hands-down leader in the PDA market. Companies such as ORiNOCO, Network Associates, and Cisco are aggressively pursuing the iPAQ as a key player in the wireless realm. Vendors are targeting software applications specifically toward the iPAQ and its capability to support a wide range of external hardware devices.

Although not yet as powerful as their desktop forefathers, PDAs are a useful extension to a home or business network. With wider deployment of 802.11b networks and the increase of free public networks, handheld devices will soon be ubiquitous among casual users. In addition, the number of corporate employees telecommuting from their PDAs through Virtual Private Networks (VPNs) is expected to grow rapidly

Chipsets - part 2

Intel 440 Chipsets

440LX

The 440LX (by this time Intel had dropped the term "Triton") was the successor to the Pentium Pro 440FX chipset and was developed by Intel to consolidate on the critical success of the Pentium II processor launched a few months earlier. The most important feature of the 440LX is support for the Accelerated Graphics Port (AGP), a new, fast, dedicated bus designed to eliminate bottlenecks between the CPU, graphics controller and system memory, which will aid fast, high-quality 3D graphics.

Other improvements with the LX are more like housekeeping, bringing the Pentium II chipset up to the feature set of the 430TX by providing support for SDRAM and Ultra DMA IDE channels. The chipset includes the Advanced Configuration and Power Interface (ACPI), allowing quick power down and up, remote start-up over a LAN for remote network management, plus temperature and fan speed sensors. The chipset also has better integration with the capabilities of the Pentium II, such as support for dynamic execution and processor pipelining.

440EX

The 440EX AGPset, based on the core technology of the 440LX AGPset, is designed for use with the Celeron family of processors. It is ACPI-compliant and extends support for a number of advanced features such as AGP, UltraDMA/33, USB and 66MHz SDRAM, to the "Basic PC" market segment.

440BX

The PC's system bus had been a bottleneck for too long. Manufacturers of alternative motherboard chipsets had made the first move, pushing Socket 7 chipsets beyond Intel's 66MHz. Intel's response came in April 1998, with the release of its 440BX chipset, which represented a major step in the Pentium II architecture. The principal advantage of the 440BX chipset is support for a 100MHz system bus and 100MHz SDRAM. The former 66MHz bus speed is supported, allowing the BX chipset to be used with older (233MHz-333MHz) Pentium IIs.

The 440BX chipset features Intel's Quad Port Acceleration (QPA) to improve bandwidth between the Pentium II processor, the Accelerated Graphics Port, 100-MHz SDRAM and the PCI bus. QPA combines enhanced bus arbitration, deeper buffers, open-page memory architecture and ECC memory control to improve system performance. Other features include support for dual processors, 2x AGP, and the Advanced Configuration Interface (ACPI).

440ZX

The 440ZX is designed for lower cost form factors without sacrificing the performance expected from an AGPset, enabling 100MHz performance in form factors like microATX. With footprint compatibility with the 440BX, the 440ZX is intended to allow OEMs to leverage BX design and validation investment to produce new systems to meet entry level market segment needs.

440GX

Released at the same time as the Pentium II Xeon processor in mid-1998, the 440GX chipset was an evolution of the 440BX AGPset intended for use with Xeon-based workstations and servers. Built around the core architecture of its 440BX predecessor, the 440GX includes support for both Slot 1 and Slot 2 implementations, a 2x AGP expansion slot, dual CPUs and a maximum of 2GB of memory.

Importantly, the chipset supports full speed backside bus operation, enabling the Pentium II Xeon's Level 2 cache to run at the same speed as the core of the CPU.

Motherboards - part 3

CMOS RAM

Motherboards also include a separate block of memory made from very low power consumption CMOS (complementary metal oxide silicon) RAM chips, which is kept "alive" by a battery even when the PC's power is off. This is used to store basic information about the PC's configuration: number and type of hard and floppy drives, how much memory, what kind and so on. All this used to be entered manually, but modern auto-configuring BIOSes do much of this work, in which case the more important settings are advanced settings such as DRAM timings. The other important data kept in CMOS memory is the time and date, which is updated by a Real Time Clock (RTC).

The CMOS memory is usually located with the real-time clock in the motherboard chipset or in a separate real-time clock chip. The PC reads the time from the RTC when it boots up, after which the CPU keeps time - which is why system clocks are sometimes out of sync. Rebooting the PC causes the RTC to be reread, increasing their accuracy.

In modern-day PCs the nonvolatile BIOS memory is generally an EEPROM or Flash memory chip. There is still a backup battery involved, but its role is not to maintain the data stored in the RAM, only to keep the RTC chip operational.

EFI

The BIOS has evolved very little since the birth of the PC in 1981, remaining a chunk of hand-crafted assembly language code most users know only for the series of arcane configuration and test messages fleetingly displayed when they turn on their PC.

Intel first signalled that all that was about to change in early 2000, with the release of the first version of its Extensible Firmware Interface (EFI) specification, a proposed standard for the architecture, interface and services of a brand new type of PC firmware, designed to provide a well-specified set of services that are consistent across all platforms.

EFI services are divided into two distinct groups, those that are available only before the operating system is loaded, known as "Boot Services," and those that are also available after EFI has assumed its minimum footprint configuration, known as "Runtime Services." Boot Services provide the breadth of functionality offered by EFI for platform configuration, initialisation, diagnostics, OS kernel image loading and other functions. Run-time Services represent a minimum set of services primarily used to query and update non-volatile EFI settings.

Services within EFI are officially specified in the EFI Specification as core services and protocol interfaces. Various protocol interfaces have been defined for access to a variety of boot devices, many of which are provided in the EFI reference implementation. Other protocol interfaces provide services for application level functions, such as memory allocation and obtaining access to a specified protocol interface.

EFI modules are generally defined as applications or drivers. Drivers conform to a model defined in the EFI specification, and are used to implement a particular protocol interface. In many cases the implementation of one protocol interface may use or enhance the functionality of an existing protocol interface, thereby providing a mechanism for an object oriented design practice called containment and aggregation.

In essence, EFI is effectively a tiny operating system in its own right, complete with its own basic networking, graphics, keyboard and storage handling software. This will allow it to have a radically different user interface to what we've been accustomed to, with support for high resolution displays and a proper GUI. The differences are far more than cosmetic though.

Since EFI is able to manage its own storage space - normally envisioned as a partition on a hard disk - hardware manufacturers will be able to add many more diagnostic and control options, and include support for different kinds of computer systems and configurations, without being constrained by the cost of expensive onboard flash memory. Moreover, the fact that EFI is developed in a high-level programming language will also spur innovation, allowing additional features to be created using standard programming tools. Such additions can include much more detailed and useful diagnostics, self-configuration programs and ways to sort out problems even if the operating system has died. Since it has its own networking capability, EFI will also be able to support remote diagnostics.

The EFI specification is primarily intended for the next generation of IA-32 and Itanium architecture-based computers, and is an outgrowth of the "Intel Boot Initiative" (IBI) program that began in 1998.

Chipsets - part 4

815 chipset

The various problems that had so delayed the introduction of Direct Rambus DRAM (DRDRAM), finally resulted in Intel doing what it had been so reluctant to do for so long - release a chipset supporting PC133 SDRAM. In fact, in mid-2000, it announced two such chipsets - formerly codenamed "Solano" - the 815 Chipset and the 815E Chipset.

Both chipsets use Intel's Graphics and Memory Controller Hub (GMCH). This supports both PC133 and PC100 SDRAM and provides onboard graphics, with a 230MHz RAMDAC and limited 3D acceleration. This gives system integrators the option of using the on-board graphics - and system memory - for lower cost systems or upgrading via an external graphics card for either AGP 4x or AGP 2x graphics capabilities.

Additionally, and like the 820E Chipset before it, the 815E features a new I/O Controller Hub (ICH2) for greater system performance and flexibility. This provides an additional USB controller, a Local Area Network (LAN) Connect Interface, dual Ultra ATA /100 controllers and up to six-channel audio capabilities. Integrating a Fast Ethernet controller directly into the chipsets makes it easier for computer manufacturers and system integrators to implement cost-effective network connections into PCs. The ICH2's enhanced AC97 interface supports full surround-sound for Dolby Digital audio found on DVD and simultaneously supports a soft modem connection.

850 chipset

Designed in tandem with the Pentium 4 processor, Intel's 850 Chipset represents the next step in the evolution of the Intel Hub Architecture, the successor to the previous northbridge /southbridge technology first seen on the 810 Chipset. Comprising the 82850 Memory Controller Hub (MCH) and 82801BA I/O Controller Hub (ICH2), the new chipset's principal features are:

a 400MHz system bus
dual RDRAM memory channels, operating in lock step to deliver 3.2 GBps of memory bandwidth to the processor
support for 1.5V AGP4x technology, allowing graphics controllers to access main memory at over 1 GBps - twice the speed of previous AGP platforms
two USB controllers, doubling the bandwidth available for USB peripherals to 24 MBps over four ports
dual Ultra ATA/100 controllers support the fastest IDE interface for transfers to storage devices.

To ensure maximum performance, the system bus is balanced with the dual RDRAM channels at 3.2 GBps, providing 3x the bandwidth of platforms based on Intel III processors and allowing better concurrency for media-rich applications and multitasking.

In the autumn of 2002, some 18 months after the i850 was first introduced, the i850E variant was released, extending the capabilities of the chipset to support Hyper-Threading, a 533MHz system bus and PC1066 memory, for Pentium 4 class processors.

Apple G4 IBook

The following article presents the very latest information on Computers. If you have a particular interest in Computers, then this informative article is required reading.

Who likes computers? Okay, come on, we all do. If you don't need them for school or work, you surely enjoy surfing the web. Whether it be a PC or a Mac, you most likely have some modern-day computer for your daily needs. The Apple G4 Ibook is a prime example of what computers are all about. I purchased my fourteen-inch notebook about a year ago, and now I can't live without it. The Apple G4 Ibook offers a standard 60 gigs, combo or super drive, and a compact size to tote around everywhere. This magnificent machine has changed my view of computers.

Coming from a background of PCs, I wasn't familiar with the Apple G4 Ibook, or the Macs at all for that matter. After a long discussion with my brother, a computer technician previously obsessed with IBM, I came to the conclusion that I would get an Apple G4 Ibook. If this professional PC lover recommended a Mac to me, what else was I to do. He now also enjoys an Ibook, and prefers it to his IBM notebook. Furthermore, I was convinced once again by a computer geek at my University, who had recently made the transition from PC to Mac, and said he wouldn't go back. This is basically due to Mac's simplicity.

If your Computers facts are out-of-date, how will that affect your actions and decisions? Make certain you don't let important Computers information slip by you.

While PCs have the standard right and left click option with their mouse, Apple G4 Ibooks have only one button. There is no right click. You want to make a command. Try open apple and a letter which refers to the command. This is easy. Open apple N will pull up a new search engine window if you're browsing the web and do not wish to close your current one. Icons can be dragged to the folders and locations of your choice. Very simple. You can hide your icons with the Apple G4 Ibook. Just scroll your mouse to the bottom of the screen and they'll magnify for your convenience.

When it comes to choosing a notebook computer, there are choices galore. You have to keep in mind what you're purchasing it for. While Macs have a reputation for video and edit capabilities, PCs are known for having better game options. All in all, both types of computers can do virtually anything you need and want them to. It all comes down to personal preference. After years of PC use, I chose the Apple G4 Ibook for its simplicity. Not to mention the wonderful virus control. One thing you will notice after buying a Mac, viruses seem to be a PC thing.

Of course, it's impossible to put everything about Computers into just one article. But you can't deny that you've just added to your understanding about Computers, and that's time well spent.

Network Media

A communication between two computers is not possible without a transmission medium. There are different types of media, which have different properties, and the selection of media depends entirely on the needs, size, and environment of the network. The most commonly used transmission medium is copper and fiber optic wires, air, and radio waves. This section deals with different types of cables used to connect the computers in a network.

The most widely used network medium is copper wire. Since it is a good conductor of electricity, the digital signals generated by the computer are converted into electrical signals so that they can be sent over the network. The disadvantage of copper wire is that there is too much energy loss if the message is sent over long distances. The different types of copper wires are described as follows:

UTP (Unshielded Twisted Pair)

Unshielded twisted pair cable is the most popular cable type used in today's networks. It consists of various pairs of unshielded twisted copper wires. It is extensively used in telephone systems and computer networking due to it low cost, easy installation and maintenance. UTP cables provide transmission speeds 4 Mbps to 100 Mbps, depending on the type and category of the cable used. The disadvantage of this cable is that it cannot be used for networks spread over long distances, as its runs are limited to 100 meters or less. As it is not shielded, it is more sensitive to electro magnetic interference. UTP cables are used in various Ethernet networks, which implement star topology. The commonly used categories of UTP cables used in computer networking are the following:

Category 3: These types of UTP cables use four pairs of twisted cable and provide transmission speed of up to 16 Mbps. They are commonly used in Ethernet networks that operate at the speed of 10 Mbps. A higher speed is also possible by these cables implementing the Fast Ethernet (100Base-T4) specifications. This cable is used mainly for telephone systems.
Category 5: This category of UTP cable is the most commonly used cable in present day networks. It consists of four twisted pairs and is used in those Ethernet networks that run at the speed of 100 Mbps. Category 5 cable can also provide a higher speed of up to 1000 Mbps.
Category 5e: It is also known as Category 5 Enhanced cable. Its specification is the same as category 5, but it has some enhanced features and is used in Ethernets that run at the speed of 1000 Mbps.
Category 6: This is the category 5e cable, but it has been designed to support high-speed networks that run at the speed of 1000 Mbps. It consists of four pairs of wire and uses all of them for data transmission. Category 6 provides more than twice the speed of Category 5e, but is also more expensive.

STP (Shielded Twisted Pair)

Shielded twisted pair cable consists of one or more pairs of twisted wires that are insulated with a metal foil to minimize electromagnetic interference. The metal shield is connected to the ground to prevent external signals from getting into and internal signals from getting out of the cable Different types of STP cables with different characteristics are available. It is extensively used in IBM networks implementing Token ring network specifications. These cables provide transmission speeds of up to 16 Mbps in Token rings and an overall speed of up to 155 Mbps. The maximum segment it provides is commonly 100 meters, although a few hundred meters is also possible. The advantage of using the STP cable is that its ability to reduce the EMI is better than the UTP cable. Its disadvantages are that it is costly and provides less speed than the UTP cable.

Coaxial Cable:

Coaxial cables were the first cables used in Ethernet networks. This cable consists of an insulator that separates the braided inner conductor and the outer conductor, which is a woven copper braid. These cables are commonly used for cable TV connections at homes. It is also used by 10 Base5 and 10 Base2 Ethernet networks. Coaxial cable is of two types, namely the Thinnet and the Thicknet, depending on the thickness of the cable. Thinnet supports a maximum segment length of 185 meters, and Thicknet can send signals up to 500 meters. The cost of the cable depends on which type of cable is used. Thinnet is less costly and easier to install, whereas Thicknet is costlier and demands more efforts in installation. The transmission speed these cables provide is between 2.5 Mbps and 10 Mbps. Coaxial cables are more resistant to EMI than the UTP cable, as they use insulators to minimize the external interference.

Fiber Optic Cable

Fiber optic cables are made up of glass, and they transmit data in the form of light, unlike the copper wire that uses electrical signals. A reflective coating that allows light beams to travel without outer interference covers the glass cable. The advantages of Fiber optic cables are that signals can be sent at a much higher speed and to very long distances without the risk of outer interference. Fiber optic cables can be categorized as Single Mode Fiber (SMF) and Multi Mode Fiber (MMF), which are explained as follows:

SMF (Single Mode Fiber) optic cable

The Single Mode Fiber optic cable supports high-speed local area networks (LAN) covering long distances and also wide area networks (WAN) that spread over different buildings or cities. It is used in 10GBase-LR Ethernet specification, which runs at the speed of 10Gbps. The SMF cable is so named because it allows only one mode of light to transmit.

MMF (Multi Mode Fiber) optic cable

The Multi Mode Fiber optic cable is also used for high-speed networks that are spread over short distances. It is used for 10GBasse-SR Ethernet standard that supports the transmission speed of 10 Gbps, Unlike the SMF cable, the MMF Cable allows the light signals to travel in more than one path. It is used extensively for short distance networking, as it is less costly than the SMF cable.

Media Connectors

Media Connectors are used to connect the cables to the computers or other devices in a network. The type of connector used in a particular network depends upon the type of cable used, as different types of cables have their own specific types of connectors. Some commonly used media connectors are listed below:

RJ-11: The RJ-11 connector is used to connect the telephone cable to the telephone jack. It is a rectangular connector, which has only four pins or conductors. The type of cable used with this connector is Category 3 UTP cable.
RJ-45: RJ-45 is a type of connector similar to an RJ-11 telephone connector, but it is larger in size because it has eight conductors. An unshielded twisted-pair (UTP) connection uses an RJ-45 connector. It is used in Ethernet networks.
F-Type: This type of connector is used with RG 6 or RG 11 coaxial cables for connecting televisions and VCRs. It consists of a single pin in the middle, which is also the central conductor. These connectors are of two types, namely 'twist-on' or 'crimp-type', in which the latter is more commonly used. F-Type connectors can be categorized according to the type of cable used and the common types are F-59, F-6, F-11, F-61 and F-71.
ST: ST stands for the "straight tip" fiber optic connector developed by AT & T. It is a popular connector used with fiber optic cables. It is used in gigabit Ethernets.
SC (Subscriber Connecter or Standard Connector): It is also a type of low cost connector used in 100 Base-FX fiber optic networks. It can be pushed into the device and can be removed by pulling out.
IEEE 1394 (Fire Wire): Institute of Electrical and Electronics Engineers (IEEE) 1394 is a standard for high-speed serial bus that provides enhanced PC connectivity for a wide range of devices. The IEEE 1394 connector is used to connect devices including consumer audiovisual components, traditional PC storage devices, and handheld devices. IEEE 1394 is also known as Fire wire.
Fiber LC (Local Connector): It is a small sized fiber optic connector, which looks like the SC connector but is half the size. It is used in gigabit Ethernets.
MT-RJ (Mechanical Transfer Registered Jack): It is also a fiber optic connector used in gigabit Ethernets.
USB (Universal Serial Bus): Universal Serial Bus (USB) is a high-speed bus standard developed by Compaq, IBM, DEC, Intel, Microsoft, NEC, and Northern Telecom. It provides the Plug and Play capability of Windows to external hardware devices. USB supports hot plugging, which means that a USB device can be installed or removed while the computer is running. USB connectors are used to connect peripheral devices, such as CD-ROM drives, keyboards, scanners, etc.

Network Components

Besides cables and connectors, various other types of network devices are used for the proper functioning of a network. Some of the commonly used network components are described as follows:

Hub: A hub is a device used to link computers in a network. It connects the computers that have a common architecture, such as Ethernet, ARCnet, FDDI, or Token Ring. All hub-computer connections for a particular network use the same type of cable, which can be twisted-pair, coaxial, or fiber-optic. Hubs are generally used in star topology networks. Token Ring hubs are also known as Multistation Access Units (MSAUs). A hub works on the physical layer of the OSI model. The following two types of hubs are available:

Active hub is a central device used to connect computers in a star network. It regenerates and retransmits deteriorated signals on the network.
Passive hub is a central device used to connect computers in a star network. It receives information through one of its ports and sends it to the computers connected to every other port. Therefore, although the information is broadcast to the network, only the destination computer reads it. A passive hub does not regenerate signals

Switch: A switch is a network connectivity device that brings media segments together at a central location. It reads the destination's MAC address or hardware address from each incoming data packet and forwards the data packet to its destination. This reduces the network traffic. Switches operate at the data-link layer of the OSI model.
Bridge: A bridge is an interconnectivity device that connects two local area networks (LANs) or two segments of the same LAN using the same communication protocols, and provides address filtering between them. Users can use this device to divide a busy network into segments and reduce network traffic. A bridge broadcasts data packets to all the possible destinations within a specific segment. Bridges operate at the data-link layer of the OSI model.
Router: Router is a device that routes data packets between computers in different networks. It is used to connect multiple networks and determines the path to be taken by each data packet to its destination computer. A Router maintains a routing table of the available routes and their conditions. By using this information, along with distance and cost algorithms, the router determines the best path to be taken by the data packets to the destination computer. A router can connect dissimilar networks, such as Ethernet, FDDI, and Token Ring, and routes data packets among them. Routers operate at the network layer (layer 3) of the Open Systems Interconnection (OSI) model.
CSU / DSU (Channel Service Unit / Data Service Unit):Channel Service Unit/Data Service Unit (CSU/DSU) acts as a modem and converts digital signals to analog signals. CSU/DSU is connected to the Ethernet router of a network segment, which in turn connects to the local network of that segment.
NIC (Network Interface Card):Network interface card (NIC) is a computer circuit board or card installed in a computer. It provides physical connection between a computer and the network. Network interface cards provide a dedicated, full-time connection to a network. Each network Interface card has a unique Media Access Control (MAC) address.

Media Access Control (MAC) address is a numerical identifier that is unique for each network interface card (NIC). MAC addresses are 48-bit values expressed as twelve hexadecimal digits, usually divided into hyphen-separated pairs, for example, FF-00-F8-32-13-19. MAC addresses are also referred to as hardware addresses, Ethernet addresses, and universally administered addresses (UAAs).

ISDN (Integrated Services Digital Network) adapter: Integrated Services Digital Network (ISDN) is a digital telephone/telecommunication network that carries voice, data, and video over an existing telephone network infrastructure. It requires an ISDN modem at the both ends of a transmission. ISDN adapter is designed to provide a single interface for hooking up a telephone, fax machine, computer, etc.
WAP (Wireless Access Point): A WAP is a communication device capable of both transmitting and receiving signals in a wireless LAN. This unit is connected to servers or directly to the network and other devices using a standard cabled network protocol.
Modem: Modem stands for Modulator-Demodulator. It is a device that enables a computer to transmit information over standard telephone lines. Since a computer stores information digitally and a telephone line is analog, a modem converts digital signals to analog and vice versa. The conversion of a digital signal to analog is known as modulation and that of an analog signal to digital is known as demodulation.
Transceiver (Media Converter):It is a communication device that can both transmit and receive signals over a medium. It is used to convert one type of media topology to another. The benefit of using transceivers is that it maintains the signal integrity./li>
Firewalls: A firewall is a combination of software and hardware that prevents data packets from coming in or going out to a specified network or computer. It is used to separate an internal network from the Internet. It analyzes all the traffic between a network and the Internet, and provides centralized access control on how users use the network. A firewall can also perform the following functions:

Block unwanted traffic.
Direct the incoming traffic to more trustworthy internal computers.
Hide vulnerable computers that are exposed to the Internet.
Log traffic to and from the private network.

Hide information, such as computer names, network topology, network device types, and internal user IDs from external users.

Chipsets - part 9

Intel 915 Express chipsets

Announced at the same time as the i925X Express", the i915 Express chipset family - codenamed Grantsdale and comprising the i915P and i915G chipsets - have the same features as its sibling with the exception of some specific performance improvements.

The principal differences between the i915 and i925X chipsets are in graphics and memory support. The i915 supports traditional dual-channel DDR memory as well as the more expensive DDR2 variety. In addition, the i915G chipset includes an integrated Intel Graphics Media Accelerator 900, optimised for Microsoft DirectX 9 and capable of providing dual independent display capability with support for the latest 16:9 ratio monitors, in addition to conventional 4:3 displays.

The 3D graphics pipeline is broken up into four major stages, including geometry processing, setup (vertex processing), texture application and rasterisation. The Intel GMA 900 is optimised to use the Intel Pentium 4 processor for software-based geometry processing (such as transform and lighting) defined by Microsoft DirectX 9.

The Intel GMA 900 handles the remaining three stages, including converting vertices to pixels, applying textures to pixels, and rasterisation - the application of lighting and other effects to produce the final pixel value. From the rasterisation stage the Intel GMA 900 writes the final pixel value to the frame buffer for display. Intel GMA 900 includes two independent display pipelines that enable operation of dual displays.

The Intel GMA 900 utilises a shared memory architecture, its support for dual-channel DDR2/533-MHz memory ensuring the memory bandwidth so critically important for quality and performance.

Intel 945 Express chipsets

Since the current chipsets didn't recognise more than one CPU, Intel had no choice but to release new chipsets at the same time as its dual-core Pentium D and Extreme Edition processors. Formerly codenamed "Lakeport", the mainstream 945 chipsets essentially provide the same features as the earlier 915 chipsets, plus support for the Pentium D processors.

However, the new chipsets aren't simply an artificial designation to allow motherboards to handle dual-core processors; there are technical differences and improvements too, albeit incremental ones.

The 945 chipset can handle front-side bus speeds up to 1066MHz and DDR2 memory up to 667MHz, providing up to 10.7GBps of peak memory bandwidth. The latter should provide a noticeable performance boost compared to DDR2-533 systems. Maximum RAM is be limited to 4GB and there's no provision for ECC support.

As with its predecessor, the 945 chipset is available in both P and G versions. The 845G differs from the 945P by the integration of Intel's GMA 950 onboard graphics on to the northbridge. This is a faster version of the GMA 900 present on the 915G chipset, up from 333MHz to 400MHz. The moderate speed hike allows a throughput of up to 1.6GTexels/sec, more than adequate for 2D applications, allowing desktop resolutions of up to 2048 x 1536 pixels at 75Hz and the ability to run two monitors simultaneously via an ADD2 extension card. However, while DirectX 9 3D performance is improved, with Vertex Shader 3.0 and T&L operations still performed in software, this is insufficient for geometry-intensive games.

In addition to providing improved graphics, the GMA 950 supports Media Expansion Cards, allowing a user to take advantage of several video output options in a single-card solution, to provide video input capability and PVR functionality and to support a wide range of display types and configurations, including support of HDTV playback on consumer electronic displays at either 720p or 1080i resolutions.

As with the previous ICH6 chips, the 945's southbridge chip is available in two versions, the basic ICH7 or the ICH7R. Both include four integrated Serial ATA ports - supporting SATA's new 3 GBps transfer rates to suitable hard drives or optical devices - 8 USB2.0 ports, support for 6 PCI slots and High-Definition Audio, a worthwhile improvement over basic AC'97. The ICH7 offers 4 PCI-Express x1 lanes that can be combined to form a single x4 port. The ICHR version differs by adding a further two PCI-Express and an enhanced version of Intel's Matrix Storage Technology.

The latter allows two separate RAID partitions to be combined on one physical set of drives. In addition to RAID0 (striping) and RAID1 (mirroring), the new version also allows for a combination of RAID5 (striping with parity) and RAID10 (stripped mirrors). It also provides support for the AHCI specification, enabling hardware-assisted Native Command Queuing (NCQ) for faster boot times and file transfers and the hot-plugging of devices.

Available as options on both 945P and 945G chipsets are an Intel Gigabit LAN interface and Intel's Active Management technology, useful for monitoring and controlling PCs in an enterprise environment.

Chipsets - part 5

i845 chipset

The fact that system builders were obliged to use expensive DRDRAM - by virtue of the absence of any Pentium 4 chipsets supporting conventional SDRAM - had been an issue ever since the Pentium 4's launch at the end of 2000. The situation changed during the course of 2001, with chipmakers SiS and VIA both releasing Pentium 4 chipsets with DDR SDRAM support. Although this was a move of which Intel disapproved, it did have the effect of boosting the appeal of the Pentium 4, whose sales hitherto had been disappointing.

In the summer of 2001 Intel eventually gave in to market pressures and released their 845 chipset - previously codenamed "Brookdale" - supporting Pentium 4 systems' use of PC133 SDRAM. Whilst the combination of i845 and PC133 SDRAM meant lower prices - given that the speed of the memory bus was about three times slower than that of the Pentium 4 system bus - it also meant significantly poorer performance than that of an i850/DRDRAM based system. The reason the i845 didn't support faster DDR SDRAM at this time was apparently because they were prevented from allowing this until the start of the following year by the terms of a contract they'd entered into with Rambus, the inventors of DRDRAM.

Sure enough, at the beginning of 2002 re-released of the i845 chipset. The new version - sometimes being referred to as i845D - differs from its predecessor only in respect of its memory controller, which now supports PC1600 and PC2100 SDRAM - sometimes referred to as DDR200 and DDR266 respectively - in addition to PC133 SDRAM. It had reportedly been Intel's original intention for the i845 chipset to support only DDR200 SDRAM - capable of providing a maximum bandwidth of 1600MBps. However, the boom in the use of DDR SDRAM - and the consequent dramatic fall in prices - caused a rethink and the subsequent decision to extend support to DDR266 (maximum bandwidth 2100MBps). The fact that the company was prepared to make this decision even though it was bound to adversely impact the market share of its i850 chipset appears to indicate that the company's apparent infatuation with DRDRAM is well and truly over.

The 400MHz system bus of the i845 solution enables up to 3.2GBps of memory bandwidth to Pentium 4 processor. Compare this with the up to 1 GBps of data transfer possible from PC133 SDRAM and it is clear why faster DDR SDRAM makes such a difference to overall system performance. Its 1.5V 4x AGP interface with provides over 1 GBps of graphics bandwidth. Other features of the i845 chipset include an 4x AGP interface, 133MBps to the PCI, support for four USB ports, six-channel audio, a generally unused LAN connect interface, dual ATA-100 controllers and CNR support.

The i845 is Intel's first chipset to use a Flip Chip BGA packaging for the chip itself. This improves heat conductivity between the Memory & Controller Hub (MCH) and its heatsink which is required for proper operation. It is also the first MCH built using a 0.18-micron process; earlier versions have been 0.25-micron. The smaller die allows another first - the incorporation of a Level 3-like write cache, significantly increasing the speed at which the CPU is able to write data. It is expected that the transition to 0.13-micron MCH/Northbridges will enable this idea to be further developed, to the point where chipsets include much larger, genuine Level 3 caches on the MCH itself. The i845 further capitalises on the performance advantage realised by its high-speed write cache by the provision of deep data buffers. These play an important role in assisting the CPU and write cache to sustain its high data throughput levels.

A number of newer versions of the i845 chipset were subsequently released, all supporting the USB 2.0 interface (which increases bandwidth up to 40 times over the previous USB 1.1 standard):

The i845G chipset, incorporating a new generation of integrated graphics - dubbed Intel Extreme Graphics - and targeted at the high-volume business and consumer desktop market segments.
The i845E chipset, which works with discrete graphics components
The i845GL chipset, designed for Celeron processor-based PCs.

i845GE chipset

The i845GE chipset was designed and optimised to support Hyper-Threading, Intel's innovative technology that achieves significant performance gains by allowing a single processor to be treated as two logical processors. Whilst not the first i845 chipset to support HT technology, it was the first in which that support was actually implemented, being launched at the same time as the first Intel's first HT-enabled desktop CPU, the 3.06GHz Pentium 4 unveiled in late 2002.

As well as supporting a faster, 266MHz version of Intel's Extreme Graphics core, the i845GE also supports a system bus speed of either 400 or 533MHz, up to DDR333 main memory and offers maximum display (digital CRT or TV) flexibility through an AGP4x connector.

The i845PE and i845GV chipsets are lower-spec variants of the i845GE, the former having no integrated graphics and the latter limiting both the Intel Extreme Graphics core and main memory support to DDR266 SDRAM.

Chipsets - part 6

Intel E7205 chipset

At the end of 2002, Intel announced the launch of a dozen Intel Xeon processor family products, including new processors, chipsets and platforms for Intel-based servers and workstations. Amongst these was one single-processor chipset, the E7205, formerly codenamed Granite Bay.

For some time the most viable way of balancing the bandwidth between the Pentium 4 CPU and its memory subsystem had been to couple the i850E chipset with dual-channel RDRAM. However, given the price and availability issues surrounding high-density RDRAM modules, this was a far from ideal solution. Despite - as its server/workstation class chipset nomenclature implies - not originally being intended for desktop use, the E7205 chipset was to provide an answer to this dilemma. With a specification which includes support for:

Dual Channel DDR266 memory bus (4.2GBps memory bandwidth)
400/533MHz FSB support (3.2GBps - 4.2GBps FSB bandwidth)
AGP 8x
USB 2.0, and
integrated LAN

it didn't take long for the motherboard manufacturers to produce boards based on the new chipset.

The E7205's memory controller is fully synchronous, meaning that the memory in E7205-based motherboards is clocked at the rate equal to the FSB frequency. Consequently, only DDR200 SDRAM may be used with CPUs supporting a 400MHz FSB and only DDR266 SDRAM with processors supporting a 533MHz FSB. The E7205 does not support DDR333 SDRAM.

With the Pentium 4 family destined to make the transition to a 800MHz Quad Pumped Bus - at which time the CPU's bus bandwidth will increase to 6.4GBps - it appears reasonable to assume that the likely way for memory subsystems to have comparable bandwidth will be the continued use of dual-channel DDR SDRAM. To that extent, the E7205 can be viewed as a prototype of the Canterwood and Springdale chipsets slated to appear in 2003.

Intel 875P chipset

Originally, Intel had planned to introduce a 800MHz FSB in the context of the Prescott, the upcoming 90nm Pentium 4 core. However, in the event this was brought forward to the spring of 2003. The rationale was to extend the Pentium 4's performance curve within the confines of their current 0.13-micron process, without having to increase clock speeds to unsustainable levels. The transition from 533MHz to 800MHz FSB was aided and abetted by an associated new chipset platform, the 875P chipset, formerly codenamed Canterwood.

A 64-bit 800MHz FSB provides 6.4GBps of bandwidth between the Memory Controller Hub (or Northbridge) and the CPU. In a move that appears to further reduce the strategic importance of DRDRAM in Intel's product planning, and that had been signalled by the earlier E7205 chipset, the memory subsystem the 875P uses to balance bandwidth between the Memory Controller Hub (MCH) and memory banks is dual channel DDR SDRAM, all of the DDR400, DDR333 and DD266 variants.

Currently, there are two different strategies being employed in dual-channel memory controllers, one in which where each memory bank has its own memory channel and an arbiter distributes the load between them and the other to actually create a wider memory channel, thereby "doubling up" on standard DDR's 64-bit data paths. The i875P employs the latter technique, with each pair of installed DIMMs acting as a 128-bit memory module, able to transfer twice as much data as a single-channel solution, without the need for an arbiter.

As a consequence, dual channel operation is dependent on a number of conditions being met, Intel specifying that motherboards should default to single-channel mode in the event of any of these being violated:

DIMMs must be installed in pairs
Both DIMMs must use the same density memory chips
Both DIMMs must use the same DRAM bus width
Both DIMMs must be either single-sided or dual-sided.

The 875P chipset also introduces two significant platform innovations:

Intel Performance Acceleration Technology (PAT), and
Communications Streaming Architecture (CSA).

PAT optimises memory access between the processor and system memory for platforms configured with both the new 800Mhz FSB and Dual-Channel DDR400 memory. CSA is a new communications architecture that creates a dedicated link from the Memory Controller Hub (MCH) to the network interface, thereby offloading network traffic from the PCI bus. Used in conjunction with the new Intel PRO/1000 CT Desktop Connection gigabit Ethernet controller, it is claimed that CSA doubles the networking bandwidth possible with traditional PCI bus-based solutions.

Additionally, the 875P chipset includes a high-performance AGP 8x graphics interface, integrated Hi-Speed USB 2.0, optional ECC is supported for users that demand memory data reliability and integrity and dual independent DMA audio engines, enabling a user to make a PC phone call whilst at the same time playing digital music streams. The chipset is also Intel's first to offer native Serial ATA (SATA), a special version designated by the "-R" suffix adding RAID - albeit only RAID 0 (data striping) - support.

Motherboards - part 2

BIOS

The All motherboards include a small block of Read Only Memory (ROM) which is separate from the main system memory used for loading and running software. The BIOS will most likely be stored in a 32-pin chip, which can typically be identified by a silver or gold sticker that shows the name of the BIOS company - such as AMIBIOS, AWARD or Phoenix - and a code that indicates the version of code it contains. If its rectangular in shape, it's what is known as a DIP (Dual In-line Package) chip. Older motherboards may have 28-pin DIP BIOS chips. If your BIOS chip is square with connections on all four sides, it is in a PLCC (Plastic Leaded Chip Carrier) package. A locating notch indicates the orientation of pin 1.

The ROM contains the PC's Basic Input/Output System (BIOS). This offers two advantages: the code and data in the ROM BIOS need not be reloaded each time the computer is started, and they cannot be corrupted by wayward applications that write into the wrong part of memory. If you have a DIP or PLCC chip that's actually soldered to your motherboard, you'll not be able to upgrade it by replacing the ROM. Modern-day BIOSes are flash upgradeable, meaning they may be updated via a floppy diskette to ensure future compatibility with new chips, add-on cards etc.

The BIOS comprises several separate routines, serving different functions. The first part runs as soon as the machine is powered on. It inspects the computer to determine what hardware is fitted and then conducts some simple tests to check that everything is functioning normally - a process called the power-on self test (POST). If any of the peripherals are plug and play devices, it's at this point that the BIOS assigns their resources. There's also an option to enter the Setup program. This allows the user to tell the PC what hardware is fitted, but thanks to automatic self-configuring BIOSes this isn't used so much now.

If all the tests are passed, the ROM then tries to determine which drive to boot the machine from. Most PCs ship with the BIOS set to check for the presence of an operating system in the floppy disk drive first (A:), then on the primary hard disk drive. Any modern BIOS will allow the floppy drive to be moved down the list so as to reduce normal boot time by a few seconds. To accommodate PCs that ship with a bootable CD-ROM, some BIOSes allow the CD-ROM drive to be assigned as the boot drive. Some also allow booting from a hard disk drive other than the primary IDE drive. In this case it would be possible to have different operating systems - or separate instances of the same OS - on different drives. Many BIOSes allow the start-up process to be interrupted to specify the first boot device without actually having to enter the BIOS setup utility itself. If no bootable drive is detected, a message is displayed indicating that the system requires a system disk. Once the machine has booted, the BIOS serves a different purpose by presenting DOS with a standardised API for the PC hardware. In the days before Windows, this was a vital function, but 32-bit "protect mode" software doesn't use the BIOS, so again it's of less benefit today.

Windows 98 (and later) provides multiple display support. Since most PCs have only a single AGP slot, users wishing to take advantage of this will generally install a second graphics card in a PCI slot. In such cases, most BIOSes will treat the PCI card as the main graphics card by default. Some, however, allow either the AGP card or the PCI card to be designated as the primary graphics card.

Whilst the PCI interface has helped - by allowing IRQs to be shared more easily - the limited number of IRQ settings available to a PC remains a problem for many users. For this reason, most BIOSes allow ports that are not in use to be disabled. With the increasing popularity of cable and ADSL Internet connections and the ever-increasing availability of peripherals that use the USB interface, it will often be possible to get by without needing either a serial or a parallel port.

Interfaces - part 14

FireWire 800

In early 2001 the battle between IEEE 1394 and USB advanced another step with the 1394 Trade Association\'s approval of specifications for a faster version of IEEE 1394, called IEEE 1394b. The new standard is backwards compatible - special cables and dual technology cards allowing users transition from the old to new standards without having to retire their legacy FireWire devices - and is expected to deliver data at up to 800Mbit/s, a significant improvement on USB 2.0\'s 480Mbit/s.

Moreover, IEEE 1394b\'s doubling of the speed of the original version of FireWire over copper wiring is only part of the story. The new standard is expected to eventually allow speeds of up to 3.2Gbit/s and support distances of 100 metres on UTP-5, plastic optical fibre and glass optical fibre, as well as significantly reducing latency times by using arbitration pipelining.

For several years IEEE 1394\'s marketing had been somewhat confusing. As well as being referred to by its technical name, the technology was also sold under Apple\'s FireWire trademark and Sony\'s iLink trademark. In the spring of 2002, the 1394 Trade Association - the group charged with licensing and promoting the standard - sought to bring about a clarification by announcing a deal with Apple that allowed the group to market and license the FireWire name along with the underlying technology. Henceforth the group would encourage companies using the technology to adopt the FireWire moniker, while not forcing them so to do.

So where does that leave the competition between FireWire and USB? So long as the likes of Intel - which integrates support for USB into its chipsets - and Microsoft - which provides support for both USB and FireWire in the latest versions of its Windows XP operating systems - maintain that the two technologies are complementary, the answer is pretty much where they were before the recent speed improvements. With built-in support on nearly every new PC, USB 2.0 will continue to connect devices on the desktop, while FireWire, with its isochronous data transfer capabilities, is likely to continue to dominate the consumer electronics market.

The table below summarises the relative performance of the current FireWire and USB standards, comparing them with the legacy serial and parallel ports they have all but replaced:

Standard	Year Introduced	Initial Speed
Serial port	1960s	20Kbit/s
Parallel port	1981	1.1Mbit/s
USB	1995	12Mbit/s
FireWire	1995	400Mbit/s
USB 2.0	2000	480Mbit/s
FireWire 800	2001	850Mbit/s

Chipsets - part 10

Intel 955X Express chipset

Formerly codenamed "Glenwood", continues this practice, essentially providing the same features as the earlier 925X chipset, plus support for Pentium Extreme Edition processors.

Ever since the release of its 865 and 875 chipsets in 2003, Intel has segregated its Pentium 4 chipsets into performance and mainstream lines, the former using northbridges equipped with the best silicon and, consequently, lower memory access latencies than on the mainstream chipsets.

In a move that appears confirms the company's desire to differentiate its XE line of processors from their mainstream series processors, the 955X chipset continues this practice, its marginally superior performance being attributed to what is rather extravagantly referred to as Intel Memory Pipeline Technology (IMPT). A further differentiation of the 955X from the 945 chipsets is its lack of support for 533MHz system bus processors.

However, the 955X's principal difference from its mainstream sibling is rather more significant; it's Intel's first desktop chipset to break the 4GB memory barrier, capitalising on the removal of the 4GB limit facilitated by 64-bit edition of Windows XP by supporting up to 8GB of addressable main memory.

Intel 965 Express chipset

In June 2006, Intel launched its 965 Express chipset, the formerly codenamed Broadwater, developed for use with platforms which feature the its Intel Core 2 processors. Incorporating Intel Fast Memory Access and an updated Memory Controller Hub (MCH) backbone architecture, the new chipset significantly increases overall system performance through the optimisation of available bandwidth and reduction of memory access latency. This updated MCH with Intel Fast Memory Access also includes wider internal data buses that support dual-channel DDR2 memory technology at 800MHz (up to 12.8GBps of peak memory bandwidth) for greater platform performance and memory flexibility.

The Intel 965 Express chipset series comprises four models:

P965: the P965 Express chipset is targeted at home users, with advancements in memory performance, system responsiveness, power efficiency and data protection.
G965: the G965 includes Intel's most advanced integrated graphics module to date - the GMA X3000-series - and is intended for use in low noise Viiv-based systems.
Q965: the Q965 is designed for business use, incorporating the integrated GMA 3000 graphics processor but also supporting the use of an add-in video card.
Q963: the Q963 has many of the same features found on Q965, but lacks support for the installation of a discrete video card.

The Intel 965P chipset is represented diagrammatically below:

and its features identified in the following table:

Feature	Description
Supports Intel Viiv Technology	Control the music, movies, games and photos you want to enjoy both from your personal entertainment collections and endless entertainment options from a wide range of Intel Viiv technology verified service providers delivered right to your living room.
1066/800/533 MHz System Bus	Supports Intel Core 2 Duo processor, Intel Pentium D processor, Intel Pentium 4 Processor with Hyper-Threading Technology (HT Technology) and all other Intel Pentium processors and Intel Celeron processors in the LGA775 socket, with scalability for future processor innovations.
PCI Express* x16 Interface	Delivers greater than 3.5 times the bandwidth over the traditional AGP 8X interface and supports the latest high-performance graphics cards.
PCI Express* x1 Interface	Offers up to 3.5 times the bandwidth over traditional PCI architecture, delivering faster access to peripheral devices and networking.
Intel Fast Memory Access	Updated Graphics Memory Controller Hub (GMCH) backbone architecture that improves system performance by optimising the use of available memory bandwidth and reducing the latency of the memory accesses.
USB Port Disable	Enables individual USB ports to be enabled or disabled as needed. This feature provides added protection of data by preventing malicious removal or insertion of data through USB ports.
Intel High Definition Audio (Intel HD Audio)	Integrated audio support enables premium digital sound and delivers advanced features such as multiple audio streams and jack re-tasking. The Dolby PC Entertainment Experience is available exclusively on systems with an enabled Intel chipset and Intel High Definition Audio.
Intel Matrix Storage Technology	With a 2nd hard drive added, provides quicker access to digital photo, video and data files with RAID 0, 5, and 10, and greater data protection against a hard disk drive failure with RAID 1, 5, and 10. Support for external SATA (eSATA) enabled the full SATA interface speed outside the chassis, up to 3Gbps.
Serial ATA (SATA) 3 Gbps	High-speed storage interface supports faster transfer rate for improved data access.
Dual-channel DDR2 Memory Support	Delivers up to 12.8GBps of bandwidth and 8 GB memory addressability for faster system responsiveness and support of 64-bit computing.
Intel Flex Memory Technology	Gives users a more flexible memory upgrade option by allowing different memory sizes to be installed while maintaining dual-channel mode/performance.
Intel Quiet System Technology (Intel QST)	Intelligent system fan speed control algorithms use operating temperature ranges more efficiently to reduce perceived system noise by minimising fan speed changes.

Motherboards - part 4

Form factor

Early PCs used the AT form factor and 12in wide motherboards. The sheer size of an AT motherboard caused problems for upgrading PCs and did not allow use of the increasingly popular slimline desktop cases. These problems were largely addressed by the smaller version of the full AT form factor, the Baby AT, introduced in 1989. Whilst this remains a common form factor, there have been several improvements since. All designs are open standards and as such don't require certification. A consequence is that there can be some quite wide variation in design detail between different manufacturers' motherboards.

BAT

The Baby AT (BAT) format reduced the dimensions of the motherboard to a typical 9in wide by 10in long, and BAT motherboards are generally characterised by their shape, an AT-style keyboard connector soldered to the board and serial and parallel port connectors which are attached using cables between the physical ports mounted on the system case and corresponding connectors located on the motherboard.

With the BAT design the processor socket is located at the front of the motherboard, and full-length expansion cards are intended to extend over it. This means that removing the processor requires the removal of some or all expansion cards first. Problems were exacerbated by the increasing speeds of Pentium-class processors. System cooling relied on the AT power supply blowing air out of the chassis enclosure and, due to the distance between the power supply and the CPU, an additional chassis fan or active heatsink became a necessity to maintain good airflow across the CPU. AT power supplies only provide 12V and 5V outputs to the motherboard, requiring additional regulators on the motherboard if 3.3V components (PCI cards or CPUs) are used. Sometimes a second heatsink was also required on these voltage regulators and together the various additional heat dissipation components caused serious obstruction for expansion slots.

Some BAT designs allow the use of either AT or ATX power supplies, and some ATX cases might allow the use of a Baby-AT motherboard.

LPX

The LPX format is a specialised variant of the Baby-AT used in low profile desktop systems and is a loose specification with a variety of proprietary implementations.

Expansion slots are located on a central riser card, allowing cards to be mounted horizontally. However, this arrangement can make it difficult to remove the motherboard, and the more complex engineering required adds to system costs. As the riser card prevents good airflow within the system case, additional chassis fans are almost always needed.

ATX

The Intel Advanced/ML motherboard, launched in 1996, was designed to solve these issues and marked the beginning of a new era in motherboard design. Its size and layout are completely different to the BAT format, following a new scheme known as ATX. The dimensions of a standard ATX board are 12in wide by 9.6in long; the mini ATX variant is typically of the order 11.2in by 8.2in.

The ATX design gets round the problem by moving the CPU socket and the voltage regulator to the right-hand side of the expansion bus. Room is made for the CPU by making the card slightly wider, and shrinking or integrating components such as the Flash BIOS, I/O logic and keyboard controller. This means the board need only be half as deep as a full size Baby AT, and there's no obstruction whatsoever to the six expansion slots (two ISA, one ISA/PCI, three PCI).

The ATX uses a new specification of power supply that can be powered on or off by a signal from the motherboard. This allows notebook-style power management and software-controlled shutdown and power-up. A 3.3V output is also provided directly from the power supply. Accessibility of the processor and memory modules is improved dramatically, and relocation of the peripheral connectors allows shorter cables to be used. This also helps reduce electromagnetic interference. The ATX power supply has a side vent that blows air from the outside directly across the processor and memory modules, allowing passive heatsinks to be used in most cases, thereby reducing system noise.

Mini-ATX is simply a smaller version of a full-sized ATX board. On both designs, parallel, serial, PS/2 keyboard and mouse ports are located on a double-height I/O shield at the rear. Being soldered directly onto the board generally means no need for cable interconnects to the on-board I/O ports. A consequence of this, however, is that the ATX needs a newly designed case, with correctly positioned cut-outs for the ports, and neither ATX no Mini-ATX boards can be used in AT-style cases.

Graph Data Structures - Adjacency List

Adjacency list

This undirected cyclic graph can be described by the list {a,b}, {a,c}, {b,c}.

In graph theory, an adjacency list is the representation of all edges or arcs in a graph as a list.

If the graph is undirected, every entry is a set of two nodes containing the two ends of the corresponding edge; if it is directed, every entry is a tuple of two nodes, one denoting the source node and the other denoting the destination node of the corresponding arc.

Typically, adjacency lists are unordered.

Application in computer science

The graph pictured above has this adjacency list representation:
a	adjacent to	b,c
b	adjacent to	a,c
c	adjacent to	a,b

In computer science, an adjacency list is a closely related data structure for representing graphs. In an adjacency list representation, we keep, for each vertex in the graph, all other vertices which it has an edge to (that vertex's "adjacency list"). For instance, the representation suggested by van Rossum, in which a hash table is used to associate each vertex with an array of adjacent vertices, can be seen as an instance of this type of representation, as can the representation in Cormen et al in which an array indexed by vertex numbers points to a singly-linked list of the neighbors of each vertex.

One difficulty with the adjacency list structure is that it has no obvious place to store data associated with the edges of a graph, such as the lengths or costs of the edges. To remedy this, some algorithms texts such as that of Goodrich and Tamassia advocate a more object oriented variant of the adjacency list structure, sometimes called an incidence list, which stores for each vertex a list of objects representing the edges incident to that vertex. To complete the structure, each edge must point back to the two vertices forming its endpoints. The extra edge objects in this version of the adjacency list cause it to use more memory than the version in which adjacent vertices are listed directly, but are a convenient location to store additional information about each edge.

Trade-offs

The main alternative to the adjacency list is the adjacency matrix. For a graph with a sparse adjacency matrix an adjacency list representation of the graph occupies less space, because it does not use any space to represent edges which are not present. Using a naive array implementation of adjacency lists on a 32-bit computer, an adjacency list for an undirected graph requires about 8e bytes of storage, where e is the number of edges: each edge gives rise to entries in the two adjacency lists and uses four bytes in each.

On the other hand, because each entry in an adjacency matrix requires only one bit, they can be represented in a very compact way, occupying only n²/8 bytes of contiguous space, where n is the number of vertices. Besides just avoiding wasted space, this compactness encourages locality of reference.

Noting that a graph can have at most n² edges (allowing loops) we can let d = e/n² denote the density of the graph. Then, 8e > n2/8, or the adjacency list representation occupies more space, precisely when d > 1/64. Thus a graph must be sparse indeed for reduced space to justify an adjacency list representation. However, this analysis is valid only when the representation is intended to store only the connectivity structure of the graph, and not any numerical information about its edges.

Besides the space tradeoff, the different data structures also facilitate different operations. It's easy to find all vertices adjacent to a given vertex in an adjacency list representation; you simply read its adjacency list. With an adjacency matrix you must instead scan over an entire row, taking O(n) time. If you, instead, want to know if two given vertices have an edge between them, this can be determined at once with an adjacency matrix, while requiring time proportional to the minimum degree of the vertices with the adjacency list.

Interfaces - part 1

INTERFACES

The PC's adaptability - its ability to evolve many different interfaces allowing the connection of many different classes of add-on component and peripheral device - has been one of the key reasons for its success. In essence, a modern PC system of today is little different to IBM's original design - a collection of components, both internal and external, interconnected by a series of electrical data highways over which data travels as it is completes the processing cycle that transforms it from an item of input to an item of output. These "buses", as they are called, connect all the PC's internal components and external devices and peripherals to its CPU and main memory (RAM).

The fastest bus of all is the connection between the processor and its primary cache, and this is kept within the CPU chip. The next level down is the system bus, which links the processor with memory, both the small amount of Static RAM (SRAM) secondary cache and the far larger main banks of Dynamic RAM (DRAM). The system bus is 64 bits wide and, for Intel-based designs, was capped at 66MHz until early 1998, when a new Pentium II chipset raised this to 100MHz. The CPU doesn't communicate directly with the memory, but through the intermediary of the System Controller chip, which manages the host bus and bridges between it and, in modern PCs, the PCI bus.

Processors using a Dual Independent Bus (DIB) architecture - present on Intel designs from the Pentium II onwards - have replaced the single system bus with two independent buses, one for accessing main memory and the other for accessing the Level 2 cache. These are referred to as the frontside bus and the backside bus respectively.

The key concept was of an open architecture based on a simple expansion bus that facilitated the easy connection of additional components and devices. Nearly two decades after its introduction, it was still possible to fit original add-on cards into a modern PC - a tribute to the staying power of the design. Whilst there have been a number of dead ends along the way, the evolution of standard expansion bus designs has been remarkably robust over the years.

Bus terminology

A modern-day system can be viewed as comprising just two classes of bus: a System Bus, connecting the CPU to main memory and Level 2 cache, and a number of I/O Busses, connecting various peripheral devices to the CPU - the latter being connected to the system bus via a "bridge", implemented in the processor's chipset.

In Dual Independent Bus (DIB) architecture systems the single system bus is replaced by a "frontside bus" for shuttling data between the CPU and main memory, and between the CPU and peripheral buses and a "backside bus" for accessing Level 2 cache. The use of dual independent buses boosts performance, enabling the CPU to access data from either of its buses simultaneously and in parallel. Over time, the terms "FSB" and "system bus" came to be used interchangeably.

The evolution of PC bus systems over a period of more than a decade has given rise to a profusion of terminology, much of it confusing, redundant or obsolete. The system bus is often referred to as the "main bus", "processor bus" or "local bus". Alternative generic terminology for an I/O bus includes "expansion bus", "external bus", "host bus" as well as, rather confusingly, "local bus".

A given system can use a number of different I/O bus systems and a typical arrangement is for the following to be implemented concurrently:

n ISA Bus, the oldest, slowest and soon to become obsolete I/O Bus system

a PCI Bus, present on Pentium-class systems since the mid-1990s

a USB Bus, the replacement for the PC's serial port which allows up to 127 devices to connected using either a hub device or by daisy-chaining.

Chipsets - part 1

CHIPSETS

A chipset or "PCIset" is a group of microcircuits that orchestrate the flow of data to and from key components of a PC. This includes the CPU itself, the main memory, the secondary cache and any devices situated on the ISA and PCI buses. The chipset also controls data flow to and from hard disks, and other devices connected to the IDE channels. While new microprocessor technologies and speed improvements tend to receive all the attention, chipset innovations are, in fact, equally important.

Although there have always been other chipset manufacturers - such as SIS, VIA and Opti - for many years Intel's "Triton" chipsets were by far the most popular. Indeed, the introduction of the Intel Triton chipset caused something of a revolution in the motherboard market, with just about every manufacturer using it in preference to anything else. Much of this was down to the ability of the Triton to get the best out of both the Pentium processor and the PCI bus, together with its built-in master EIDE support, enhanced ISA bridge and ability to handle new memory technologies like EDO and SDRAM. However, the new PCI chipsets" potential performance improvements will only be realised when used in conjunction with BIOSes capable of taking full advantage of the new technologies on offer.

During the late 1990s things became far more competitive, with Acer Laboratories (ALI), SIS and VIA Technologies all developing chipsets designed to operate with Intel, AMD and Cyrix processors. 1998 was a particularly important year in chipset development, with what had become an unacceptable bottleneck - the PC's 66MHz system bus - to finally being overcome. Interestingly, it was not Intel but rival chipmakers that made the first move, pushing Socket 7 chipsets to 100MHz. Intel responded with its 440BX, one of many chipsets to use the ubiquitous Northbridge/Southbridge architecture. It was not long before Intel's hold on the chipset market loosened further still, and again, the company had no-one but itself to blame. In 1999, its single-minded commitment to Direct Rambus DRAM (DRDRAM) left it in the embarrassing position of not having a chipset that supported the 133MHz system bus speed its latest range of processors were capable of. This was another situation its rivals were able to exploit, and in so doing gain market share.

The following charts the evolution of Intel chipsets over the years, from the time of its first Triton chipset. During this time there have also been a number of special chipsets optimised for the Pentium Pro or designed for use with notebook PCs.

Triton Chipsets

Triton430FX

Introduced in early 1995, the 82430FX - to give it its full name - was Intel's first Triton chipset and conformed to the PCI 2.0 specification. It introduced support for EDO memory configurations of up to 128MB and for pipelined burst cache and synchronous cache technologies. However, it did not support a number of emerging technologies such as SDRAM and USB and was superseded in 1996 - little more than a year after its launch - by a pair of higher performance chipsets.

Triton430VX

The Triton 430VX chipset conforms to the PCI 2.1 specification, and is designed to support Intel's Universal Serial Bus (USB) and Concurrent PCI standards. With the earlier 430FX, a bus master (on the ISA or PCI bus), such as a network card or disk controller, would lock the PCI bus whenever it transferred data in order to have a clear path to memory. This interrupted other processes, and was inefficient because the bus master would never make full use of the 100 MBps bandwidth of the PCI bus. With Concurrent PCI, the chipset can wrest control of the PCI bus from an idle bus master to give other processes access on a timeshare basis. Theoretically, this should allow for data transfer rates of up to 100 MBps, 15% more than the 430FX chipset, and smooth intensive PCI tasks such as video playback when bus masters are present.

The 430VX chipset was aimed fairly and squarely at the consumer market. It was intended to speed up multimedia and office applications, and it was optimised for 16-bit. Furthermore, it was designed to work with SDRAM, a special type of memory that's optimised for intensive multimedia processing. Although the performance gains are slight for this type of RAM over EDO RAM, the advantage is that it can operate efficiently from a single Dual In-line Memory Module (DIMM) and does not need to be paired.

The 430VX provided improved EDO memory timings which was supposed to allow cacheless systems to be built without compromising performance, at least compared to a PC with asynchronous cache. In practice, though, most manufacturers continued to provide at least some secondary cache, with most using synchronous cache to maximise performance.

Triton430HX

The Triton 430HX chipset is geared towards business machines and was developed with networking, video conferencing and MPEG video playback in mind. It supports multiple processors, has been optimised for 32-bit operation and to work with large memory arrays (up to 512MB) and provides error control (ECC) facilities on the fly when 32-bit parity SIMMs are used. The 430HX does not support SDRAM.

The biggest difference between the HX and VX chipsets is the packaging. Where the VX consists of four separate chips, all built using the traditional plastic quad flat packaging, the HX chipset comprises just two chips, the 82439HX System Controller (SC), which manages the host and PCI buses, and the 82371SB PIIX3 for the ISA bus and all the ports.

The SC comes in a new ball grid array (BGA) packaging which reduces overall chip size and makes it easier to incorporate onto motherboard designs. It exerts the greatest influence on the machine's CPU performance, as it manages communications between the CPU and memory. The CPU has to be fed data from the secondary cache as quickly as possible, and if the necessary data isn"t already in the cache, the SC fetches it from main memory and loads it into the cache. The SC also ensures that data written into cache by the CPU is "flushed" back into main memory.

The PIIX3 chip manages the many processes involved in getting data into and out of RAM from the other devices in the PC. It provides two EIDE channels, both of which can accept two drives. IDE drives contain most of the controlling circuitry built into the hard disk itself, so the PIIX is mainly responsible for shifting data from the drives into RAM and back as quickly as possible. It also provides two 115,200bit/s buffered serial ports, an error correcting Enhanced Parallel Port, a PS/2 mouse port and a keyboard controller. The PIIX also supports additional connections that many motherboards have yet to adopt as the norm, such as a Universal Serial Bus connector and an infrared port.

Triton430TX

The Triton 430TX includes all the features found on the earlier chipsets, including Concurrent PCI, USB support, aggressive EDO RAM timings and SDRAM support and is optimised for MMX processors and is designed to be used in both desktop and mobile computers.

The Triton 430TX also continues the high-integration two-chip BGA packaging first seen with the 430HX chipset, comprising the 82439TX System Controller (MTXC) and the 82371AB PCI ISA IDE Xcelerator (PIIX4). The former integrates the cache and main memory DRAM control functions and provides bus control to transfers between the CPU, cache, main memory, and the PCI Bus. The latter is a multi-function PCI device implementing a PCI-to-ISA bridge function, a PCI IDE function, a Universal Serial Bus host/hub function, and an Enhanced Power Management function.

The diagram below provides an overview of the overall architecture and shows the division of functionality between the System Controller and the Peripheral Bus Controller components - which are often referred to as "Northbridge" and "Southbridge" chipsets respectively.

The TX incorporates the Dynamic Power Management Architecture (DPMA) which reduces overall system power consumption and offers intelligent power-saving features like suspend to RAM and suspend to disk. The TX chipset also supports the new Ultra DMA disk protocol which enables a data throughput of 33 MBps from the hard disk drive to enhance performance in the most demanding applications.

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Bitdefender Internet Security Suite 2008 Review

This security suite excels in protecting your pc against pesky viruses and other web threats that can infiltrate your computer. This software is exceptionally easy to use and runs quietly in the background without taxing your RAM and bogging down your applications.

Firewall:

West Coast Labs (W.C.L.) certifies BitDefender s Firewall. It continually monitors all incoming and outgoing data to and from your PC. Within the firewall tab, you can see a real time graph so you can visually see your computer s communication with the Internet. BitDefender also monitors your Wi Fi connection.

You can configure the firewall by choosing one of four different settings: Ask, Allow all White Listed, Allow All and Deny All. Each setting differs as to what information it will allow in and out of your computer and whether it prompts you before transferring data.

Antivirus:

Virus detecting is BitDefender s specialty; this software continually passes all tests given by ICSA, VB 100% and W.C.L. This suite continually scans your computer for threats, and with the click of a button, you can scan your entire system or choose a specific area to scan like removable drives, memory or documents.

You are able to configure the antivirus settings to meet your needs. Choose one of three different levels of security aggressive, default or permissive. Or, you can set a custom level where you choose exactly what you want to scan and what you don t.

Antispyware:

In the antispyware tab, you can access the spyware statistics that include cookies blocked, registry blocked, scripts blocked and more. Furthermore, you can choose the protection level. You have the options of aggressive, default or permissive.

BitDefender will stop all major threats including adware, keyloggers, trojans and browser hijackers to keep your private information safe.

Other Security/Features:

BitDefender Internet Security comes complete with customizable web filters as part of the parental control function. You can set up user accounts and set specific criteria for the web filter per account. This will keep children away from potentially dangerous sites, pc damaging downloads or material you would rather they not access. Additionally, this software will scan email messages for keywords so you can ensure your kids aren t receiving harmful emails.

You can also set each account so the user can only access certain applications and use the computer during set hours of the day.

New with BitDefender Total Security are tune-up features. You can improve your PC's performance by removing unnecessary files directly from the BitDefender interface.

Ease of Use:

The BitDefender Internet Security interface is simple to navigate with organized tabs. Simply select General, Antivirus, Firewall, Antispam, Antispyware, Parental Control or Update to configure the settings of that function.

Ease of Installation/Setup:

We didn t have any problems installing or setting up BitDefender.

Help/Support:

Softwin provides tutorials, user manuals, and, on their website, FAQs. You can find a lot of valuable information here and these sources will answer most of your questions. For further questions, you can contact customer support by phone, email or online chat. We used the chat feature and the representative was cordial and helpful.

Summary:

BitDefender Internet Security suite retails for $39.95. This is a budget friendly price for a top notch product. BitDefender will defend your computer and personal information so you can surf the web at ease.

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Basic Data Structures - Data Type

Data type

A data type is a constraint placed upon the interpretation of data in a type system in computer programming. Common types of data in programming languages include primitive types (such as integers, floating point numbers or characters), tuples, records, algebraic data types, abstract data types, reference types, classes and function types. A data type describes representation, interpretation and structure of values manipulated by algorithms or objects stored in computer memory or other storage device. The type system uses data type information to check correctness of computer programs that access or manipulate the data.

Machine data types

All data in computers based on digital electronics is represented as bits (alternatives 0 and 1) on the lowest level. The smallest addressable unit of data is a group of bits called a byte (usually an octet, which is 8 bits). The unit processed by machine code instructions is called a word (as of 2006, typically 32 or 64 bits). Most instructions interpret the word as a binary number, such that a 32-bit word can represent unsigned integer values from 0 to 232 − 1 or signed integer values from − 231 to 231 − 1. Because of two's complement, the machine language and machine don't need to distinguish between these unsigned and signed data types for the most part.

There is a specific set of arithmetic instructions that use a different interpretation of the bits in word as a floating-point number.

These can include the following (depending on the programming language):

RECORD - a set of variable types - Example: a row in a database table
TABLE - an indexed column in a database
NESTED TABLE - unconstrained, single dimension array of a single or composite type
VARRAY - fixed size collection of same type variable

Integer Numbers

An integer number can hold a whole number, but no fraction. For the value to be negative, you must place a hyphen symbol (-) before the value. You must not use commas as part of the number as this would generate a syntax error. Examples of integer numbers:
42
10000
-233000
-100

Real Numbers:

A real number can hold a whole number or a fractional number that uses a decimal point. For the value to be negative, you must place a hyphen symbol (-) before the value. Examples of real numbers:

20.0005
99.9
-5000.12
-9999.9991

Strings:

String data is non-numerical, and is used to store characters and words. All strings consist of characters enclosed within double quotation marks. The string data can include numbers and other numerical symbols but will be treated as text. Examples of strings are:

"A"
"Hello World"
"Telephone"
"I am 6000 years old"
"1.2.3.4.5.6.7.8.9"

Each string can consist of as many characters as the memory allows. You can also have a string with no data whatsoever, represented by an empty pair of double quotation marks.

Numeric datatype ranges

Each numeric datatype has a maximum and minimum value known as the range. It is important to know the ranges, especially when dealing with smaller types, as you can only store numbers that lie within that range. Attempting to store a number outside the range may lead to compiler/runtime errors, or to incorrect calculations (due to truncation) depending on the language being used.

The range of a variable is based on the number of bytes used to save the value, and an integer datatype is usuallyable to store 2n values (where n is the no. of bits). For other data types (e.g. floating point values) the range is more complicated and will vary depending on the method used to store it. There are also some types that do not use entire bytes, e.g. a boolean that requires a single bit, and represents a binary value (although in practice a byte is often used, with the remaining 7 bits being redundant). Some programming languages also allow the opposite direction, that is, the programmer defines the range and precision needed to solve a given problem and the compiler chooses the most appropriate integer or floating point type automatically.The following table lists a set of common of numeric datatypes and their ranges:

Data Type	Size	Range
Integer types
Boolean	1 bit (though often stored as 1 byte)	0 to 1
Byte	8 bits	0 to 255
Word	2 bytes	0 to 65535
Double Word	4 bytes	0 to 4,294,967,295
Integer	4 bytes	2,147,483,648 to 2,147,483,647
Double Integer	8 bytes	9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
Floating point types
Real	4 bytes	1E-37 to 1E+37 (6 decimal digits)
Double Float	8 bytes	1E-307 to 1E+308 (15 decimal digits)

Chipsets - part 3

810 AGPset

Formerly codenamed "Whitney", the 810 AGPset finally reached the market in the summer of 1999. It is a three-chip solution comprising the 82810 Graphics Memory Controller Hub (GMCH), 82801 I/O Controller Hub (ICH) and 82802 Firmware Hub (FWH) for storing the system and video BIOS. A break from tradition is that these components don't communicate with each other over the PCI bus. Instead, they use a dedicated 8-bit 266 MBps proprietary bus, thereby taking load off the PCI subsystem. The SDRAM memory interface is also unusual in that it runs at 100MHz irrespective of the system bus speed. There's no ISA support, but it could be implemented if a vendor added an extra bridge chip.

At the time of its launch, there were two versions of the 810 - the 82810 and 81810-DC100. The former is 66MHz part with no graphics memory, while the latter is a 100MHz-capable chip with support for 4MB of on-board graphics memory. The Direct AGP graphics architecture uses 11MB of system memory for frame buffer, textures and Z-buffer if no display cache is implemented. This drops to 7MB if the display cache is implemented. The whole configuration is known as Direct Video Memory technology. Also incorporated in the chipset is an AC-97 CODEC, which allows software modem and audio functionality. Vendors can link this to an Audio Modem Riser (AMR) slot to facilitate future plug-in audio or modem upgrades.

In the autumn of 1999 a subsequent version of the chipset - the 810E - extended support processors with a 133 MHz system bus. The Intel 810E chipset features a unique internal gear arbitration, allowing it to run seamlessly with 66 MHz, 100 MHz and 133 MHz processor busses.

As the cost of processors come down, the marginal costs of the motherboard, graphics and sound subsystems becomes an increasingly important factor in vendors' efforts to hit ever-lower price points. However, high levels of integration can be a double-edged sword: it reduces vendors' bill-of-materials (BOM) costs, but also limits their capability for product differentiation. Many manufacturers defer their decisions on graphics and sound options to late in the production cycle in order to maintain a competitive marketing advantage. Given that other highly integrated solutions - such as Cyrix's Media GX - haven't fared particularly well in the past, the 810 AGPset represents a bold move on Intel's part and one that signals the company's determination to capture a greater share of the "value PC" market which had been effectively ceded to AMD and Cyrix over the prior couple of years.

820 chipset

Originally scheduled to be available concurrently with the Pentium III processor in the spring of 1999, Intel's much delayed 820 chipset was finally launched in November that year. Those delays - which had left Intel in the position not having a chipset that supported the 133MHz system bus speed their latest range of processors were capable of - were largely due to delays in the production of Direct Rambus DRAM (DRDRAM), a key component in Intel's 133MHz platform strategy.

Direct RDRAM memory provides a memory bandwidth capable of delivering 1.6 GBps of maximum theoretical memory bandwidth - twice the peak memory bandwidth of 100MHz SDRAM systems. Additionally, the 820's support for AGP 4x technology allows graphics controllers to access main memory at more than 1 GBps - twice that of previous AGP platforms. The net result is the significantly improved graphics and multimedia handling performance expected to be necessary to accommodate future advances in both software and hardware technology.

The 820 chipset employs the Accelerated Hub Architecture that is offered in all Intel 800 series chipsets - the first chipset architecture to move away from the traditional Northbridge /Southbridge design. It supports a bandwidth of 266 MBps and, with it's optimised arbitration rules which allow more functions to run concurrently, delivers significantly improved audio and video handling. The chipset's three primary components are:

Memory Controller Hub
I/O Controller Hub, and
Firmware Hub.

The Memory Controller Hub provides a high-performance interface for the CPU, memory and AGP and supports up to 1GB of memory via a single channel of RDRAM using 64-, 128- and 256-Mbit technology. With an internal bus running at 1.6 GBps and an advanced buffering and queuing structure, the Memory Hub Controller balances system resources and enables concurrent processing in either single or dual processor configurations.

The I/O Controller Hub forms a direct connection from the PC's I/O devices to the main memory. This results in increased bandwidth and significantly reduced arbitration overhead, creating a faster path to main memory. To capitalise further on this faster path to main memory, the 820 chipset features an integrated AC97 controller in addition to an ATA66 drive controller, dual USB ports and PCI add-in cards.

The Firmware Hub stores system and video BIOS and includes a first for the PC platform - a hardware-based random number generator. The Intel RNG provides truly random numbers through the use of thermal noise - thereby enabling stronger encryption, digital signing and security protocols. This is expected to be of particular benefit to the emerging class of e-commerce applications.

The i820 hadn't long been on the market before Intel - recognising that the price of RDRAM was likely to remain high for sometime - designed and released an add-on chip, the 82805 Memory Translator Hub (MTH), which, when implemented on the motherboard, allowed the use of PC100 SDRAM. Sitting between the i820's Memory Controller Hub (MCH) and the RDRAM memory slots, the MTH chip translates the Rambus memory protocol that's used by RDRAM into the parallel protocol required by SDRAM, thereby allowing the i820 to use this much more price attractive memory.

Within a few months, a bug in the MTH component came to light. This was serious enough to cause Intel to recall all MTH-equipped i820-motherboards. Since it wasn't possible to replace the defective chip Intel took the extraordinary step of giving every owner of an MTH-equipped i820 motherboard a replacement non-MTH motherboard as well as RDRAM to replace the SDRAM that was used before!

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Motherboards - part 6

Riser architectures

In the late 1990s, the PC industry developed a need for a riser architecture that would contribute towards reduced overall system costs and at the same time increase the flexibility of the system manufacturing process. The Audio/Modem Riser (AMR) specification, introduced in the summer of 1998, was the beginning of a new riser architecture approach. AMR had the capability to support both audio and modem functions. However, it did have some shortcomings, which were identified after the release of the specification. These shortcomings included the lack of Plug and Play (PnP) support, as well as the consumption of a PCI connector location.

Consequently, new riser architecture specifications were defined which combine more functions onto a single card. These new riser architectures combine audio, modem, broadband technologies, and LAN interfaces onto a single card. They continue to give motherboard OEMs the flexibility to create a generic motherboard for a variety of customers. The riser card allows OEMs and system integrators to provide a customised solution for each customer's needs. Two of the most recent riser architecture specifications include CNR and ACR.

Intel's CNR (Communication and Networking Riser) specification defines a hardware scalable OEM motherboard riser and interface that supports the audio, modem, and LAN interfaces of core logic chipsets. The main objective of this specification is to reduce the baseline implementation cost of features that are widely used in the "Connected PC", while also addressing specific functional limitations of today's audio, modem, and LAN subsystems.

PC users' demand for feature-rich PCs, combined with the industry's current trend towards lower cost, mandates higher levels of integration at all levels of the PC platform. Motherboard integration of communication technologies has been problematic to date, for a variety of reasons, including FCC and international telecom certification processes, motherboard space, and other manufacturer specific requirements.

Motherboard integration of the audio, modem, and LAN subsystems is also problematic, due to the potential for increased noise, which in-turn degrades the performance of each system. The CNR specifically addresses these problems by physically separating these noise-sensitive systems from the noisy environment of the motherboard.

With a standard riser solution, as defined in this specification, the system manufacturer is free to implement the audio, modem, and/or LAN subsystems at a lower bill of materials (BOM) cost than would be possible by deploying the same functions in industry-standard expansion slots or in a proprietary method. With the added flexibility that hardware scalability brings, a system manufacturer has several motherboard acceleration options available, all stemming from the baseline CNR interface.

The CNR Specification supports the five interfaces:

AC97 Interface - Supports audio and modem functions on the CNR card
LAN Connect Interface (LCI) - Provides 10/100 LAN or Home Phoneline Networking capabilities for Intel chipset based solutions
Media Independent Interface (MII) - Provides 10/100 LAN or Home Phoneline Networking capabilities for CNR platforms using the MII Interface
Universal Serial Bus (USB) - Supports new or emerging technologies such as xDSL or wireless
System Management Bus (SMBus) - Provides Plug and Play (PnP) functionality on the CNR card.

Each CNR card can utilise a maximum of four interfaces by choosing the specific LAN interface to support.

The rival ACR specification is supported by an alliance of leading computing and communication companies, whose founders include 3COM, AMD, VIA Technologies and Lucent Technologies. Like CNR, it defines a form factor and interfaces for multiple and varied communications and audio subsystem designs in desktop OEM personal computers. Building on first generation PC motherboard riser architecture, ACR expands the riser card definition beyond the limitation of audio and modem codecs, while maintaining backward compatibility with legacy riser designs through an industry standard connector scheme. The ACR interface combines several existing communications buses, and introduces new and advanced communications buses answering industry demand for low-cost, high-performance communications peripherals.

ACR supports modem, audio, LAN, and xDSL. Pins are reserved for future wireless bus support. Beyond the limitations of first generation riser specifications, the ACR specification enables riser-based broadband communications, networking peripheral and audio subsystem designs. ACR accomplishes this in an open-standards context.

Like the original AMR Specification, the ACR Specification was designed to occupy or replace an existing PCI connector slot. This effectively reduces the number of available PCI slots by one, regardless of whether the ACR connector is used. Though this may be acceptable in a larger form factor motherboard, such as ATX, the loss of a PCI connector in a microATX or FlexATX motherboard - which often provide as few as two expansion slots - may well be viewed as an unacceptable trade-off. The CNR specification overcomes this issue by implementing a shared slot strategy, much like the shared ISA /PCI slots of the recent past. In a shared slot strategy, both the CNR and PCI connectors effectively use the same I/O bracket space. Unlike the ACR architecture, when the system integrator chooses not to use a CNR card, the shared PCI slot is still available.

Although the two specifications both offer similar functionality, the way in which they are implemented are quite dissimilar. In addition to the PCI connector/shared slot issue, the principal differences are as follows:

ACR is backwards compatible with AMR, CNR isn't
ACR provides support xDSL technologies via its Integrated Packet Bus (IPB) technology; CNR provides such support via the well-established USB interface
ACR provides for concurrent support for LCI (LAN Connect Interface) and MII (Media Independent Interface) LAN interfaces; CNR supports either, but not both at the same time
The ACR Specification has already reserved pins for a future wireless interface; the CNR specification has the pins available but will only define them when the wireless market has become more mature.

Ultimately, motherboard manufacturers are going to have to decide whether the ACR specification's additional features are worth the extra cost.

Lavasoft Adaware Ad Aware Pro 2007 Review

Lavasoft was one of the first companies to recognize the dangers posed by spyware and to offer a solution. For ages, its Ad-Aware was one of the very few antispyware solutions available. In recent years Ad-Aware's star has dimmed, but with the release of Ad-Aware 2007 Pro, it's back in the spotlight with a fully redesigned engine and a spiffed-up interface. The question is has the company done enough to the actual performance of the app that you can trust it to protect your computer against spyware?

To install Ad-Aware, you download the same file regardless of the version you've chosen it always starts life as the Free version. If you've purchased a subscription for Plus ($26.95) or Pro ($39.95), you simply enter the registration code to activate the additional features. And if you don't renew your subscription before it expires, you'll still have the free version's spyware-removal functionality.

Free Spyware Removal, Worth the Price

After verifying with Lavasoft that spyware removal in the free version is exactly the same as in the Plus or Pro versions, I loaded AAW Free onto all of my malware-infested test systems. Again and again, I ran into an odd problem with the test systems. Every time I clicked the Update button to be sure of having the latest software and definitions, I got a "server busy" error. If I tried to run a scan, it said "Can't start Full Scan, scanner is busy." According to Lavasoft, what both of these messages really mean is that an automatic update is already in progress in the background; a coming release will change those messages to explain more clearly what's going on. That's a good thing; the current messages are misleading.

The nasties installed on my test systems include adware, spyware, Trojan horses, rootkits, polymorphic threats, even rogue antispyware programs. AAW's scan was speedy about 12 minutes on my standard clean test system and not a lot longer on the infested systems. The combined virus/spyware scan in Spy Sweeper and Norton Internet Security took about a half-hour; Spyware Doctor took much longer. One system's rabid malware kept AAW from installing, and it wouldn't install in Safe Mode even after I applied Registry tweaks supplied by Lavasoft. Another system installed okay but wouldn't scan; scanning in Safe Mode solved that problem. Yet another went into a blue-screen death spiral after malware removal I never did get that one fixed, even with Lavasoft's help. Ouch!

AAW reports its findings in two separate groups, Critical Objects and Privacy Objects. The latter group includes low-threat items such as tracking cookies. Every single one of my samples that AAW detected wound up on the Critical Object list, which makes sense. For each object AAW reports a "Threat Analysis Index" from 1 to 10 and an expandable listing of all the file and Registry traces associated with that threat. You check off the ones you want to remove (typically all of them) and click Quarantine or Remove. If necessary, AAW queues up removal of entrenched threats for the next reboot and warns that a reboot is needed. But unlike most antispyware products, it does not offer to perform that reboot automatically you'll have to remember to do it yourself.

My high hopes for this updated tool's success were quickly dashed. It did a good job of removing simple adware and spyware and even handled rogue antispyware programs well. But against Trojans and rootkits, it was almost completely ineffective. Lavasoft verified that AAW can't detect files that are hidden from the Windows API using rootkit techniques; rootkit protection is currently in development and planned for a future version. On a scale of 10, with 10 meaning it both detected and removed every threat, AAW scored 5.9. Tested against the same gang of nasties, Spy Sweeper scored 9.0 and Spyware Doctor nosed ahead with 9.1.

I separately tested the product's ability to detect and remove commercial keyloggers; in this test, it scored a big fat goose-egg. Lavasoft verified that they do not attempt to remove such programs. "We want to respect the business model of the companies that manufacture monitoring software." I can see their point, but I'd at least like to be told that monitoring software is on the system.

As mentioned, the Ad-Watch real-time protection is a feature included only with the paid Plus or Pro versions. I installed AAW Pro on a clean system and started tossing malware installers at it, to see how well it would protect me. As noted above, Lavasoft made a decision to ignore commercial keyloggers, and indeed it ignored those samples. Of course if an industrial spy or private eye is sitting at your desk installing a keylogger, you've got problems that software alone can't solve.

Ad-Watch pops up an alert when it detects malware launching and asks whether to block it I always blocked those. The app also pops up alerts when any program, malicious or legitimate, makes certain system changes such as adding itself to the startup sequence. I allowed the latter sort of change unless the program was identified as malicious. Ad-Watch does include an option to skip the popups and always allow or block, but unfortunately it doesn't distinguish between the known-malware popups and the system change popups.

Just as in the removal testing, AAW's effectiveness decreased as the nastiness of the threats increased. It blocked installation of many spyware and adware samples, but missed most of the Trojans and rootkits. Overall it scored 5.0 out of 10 on this test. SUPERAntispyware and iolo's System Shield 3 didn't do well in testing, but they did better than that, with 5.9 and 5.2, respectively. At the high end, Spy Sweeper scored 8.1 and Spyware Doctor an amazing 9.8 against this same test set.

AAW supports Internet Explorer, Firefox, and Opera, and its TrackSweep module automatically wipes away traces of your Web surfing in all three. There's a built-in option to set a System Restore point after cleanup. They say this will help you recover after a spyware attack, but I'd be happier if the product simply prevented that attack from ever happening.

Other features are specific to the Plus and Pro versions. Besides Ad-Watch real-time protection, the Plus version offers automatic updates (AAW Free users must update manually), custom scans, and scan scheduling, as well as a HOSTS file editor (which lets ber-geeks check to be sure that malware hasn't added HOSTS file lines that redirect attempts to reach valid domain sites to fraudulent copies). In addition to all those, he Pro version offers some features that are primarily aimed at the most technical users. With it you can launch scans from the command line, monitor network traffic, and get a detailed view of all running processes.

Still, no amount of bonus features can make up for that Ad-Aware 2007 just doesn't stand up to modern threats. I'm pleased to see that Lavasoft has energized the product's development. The new scan engine is fast, and the interface is slick. You might consider using the free version as a "second opinion" scanner. But don't pin your system's security on Ad-Aware; it's not ready for that responsibility.

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Interfaces - part 11

USB

Developed jointly by Compaq, Digital, IBM, Intel, Microsoft, NEC and Northern Telecom, the Universal Serial Bus (USB) standard offers a new standardised connector for attaching all the common I/O devices to a single port, simplifying today's multiplicity of ports and connectors. Significant impetus behind the USB standard was created in September of 1995 with the announcement of a broad industry initiative to create an open host controller interface (HCI) standard for USB. Backed by 25 companies, the aim of this initiative was to make it easier for companies - including PC manufacturers, component vendors and peripheral suppliers - to more quickly develop USB-compliant products. Key to this was the definition of a non-proprietary host interface - left undefined by the USB specification itself - which enabled connection to the USB bus. The first USB specification was published a year later, with version 1.1 being released in the autumn of 1998.

Up to 127 devices can be connected, by daisy-chaining or by using a USB hub which itself has a number of USB sockets and plugs into a PC or other device. Seven peripherals can be attached to each USB hub device. This can include a second hub to which up to another seven peripherals can be connected, and so on. Along with the signal USB carries a 5v power supply so small devices, such as hand held scanners or speakers, do not have to have their own power cable.

Devices are plugged directly into a four-pin socket on the PC or hub using a rectangular Type A socket. All cables that are permanently attached to the device have a Type A plug. Devices that use a separate cable have a square Type B socket, and the cable that connects them has a Type A and Type B plug.

USB 1.1 overcame the speed limitations of UART-based serial ports, running at 12 Mbit/s - at the time, on a par with networking technologies such as Ethernet and Token Ring - and provided more than enough bandwidth for the type of peripheral device is was designed to handle. For example, the bandwidth was capable of supporting devices such as external CD-ROM drives and tape units as well as ISDN and PABX interfaces. It was also sufficient to carry digital audio directly to loudspeakers equipped with digital-to-analogue converters, eliminating the need for a soundcard. However, USB wasn't intended to replace networks. To keep costs down its range is limited to 5 metres between devices. A lower communication rate of 1.5 Mbit/s can be set-up for lower-bit-rate devices like keyboards and mice, saving space for those things which really need it.

USB was designed to be user-friendly and is truly plug-and-play. It eliminates the need to install expansion cards inside the PC and then reconfigure the system. Instead, the bus allows peripherals to be attached, configured, used, and detached while the host and other peripherals are in operation. There's no need to install drivers, figure out which serial or parallel port to choose or worry about IRQ settings, DMA channels and I/O addresses. USB achieves this by managing connected peripherals in a host controller mounted on the PC's motherboard or on a PCI add-in card. The host controller and subsidiary controllers in hubs manage USB peripherals, helping to reduce the load on the PC's CPU time and improving overall system performance. In turn, USB system software installed in the operating system manages the host controller.

Data on the USB flows through a bi-directional pipe regulated by the host controller and by subsidiary hub controllers. An improved version of bus mastering allows portions of the total bus bandwidth to be permanently reserved for specific peripherals, a technique called isochronous data transfer. The USB interface contains two main modules: the Serial Interface Engine (SIE), responsible for the bus protocol, and the Root Hub, used to expand the number of USB ports.

The USB bus distributes 0.5 amps (500 milliamps) of power through each port. Thus, low-power devices that might normally require a separate AC adapter can be powered through the cable - USB lets the PC automatically sense the power that's required and deliver it to the device. Hubs may derive all power from the USB bus (bus powered), or they may be powered from their own AC adapter. Powered hubs with at least 0.5 amps per port provide the most flexibility for future downstream devices. Port switching hubs isolate all ports from each other so that one shorted device will not bring down the others.

The promise of USB was a PC with a single USB port onto which would be connected one large, powered device - like a monitor or a printer - which would act as a hub, linking up all the other smaller devices such as mouse, keyboard, modem, document scanner, digital camera and so on. Since many USB device drivers did not become available until after its release, this promise was never going to be realised before the availability of Windows 98. However, even post-Windows 98 its take-up was initially disappointing.

There were a number of reasons for this. Some had complained that the USB architecture was too complex and that a consequence of having to support so many different types of peripheral was an unwieldy protocol stack. Others argued that the hub concept merely shifts expense and complexity from the system unit to the keyboard or monitor. However, probably the biggest impediment to USB's acceptance was the IEEE 1394 FireWire standard.

Developed by Apple Computer, Texas Instruments and Sony and backed by Microsoft and SCSI specialist Adaptec, amongst others, IEEE 1394 was another high-speed peripheral bus standard. It was supposed to be complementary to USB, rather than an alternative, since it's possible for the two buses to coexist in a single system, in a manner similar to today's parallel and serial ports. However, the fact that digital cameras were far more likely to sport an IEEE 1394 socket than a USB port gave other peripheral manufacturers pause for thought.

Interfaces - part 13

USB 2.0

While USB was originally designed to replace legacy serial and parallel connections, notwithstanding the claims that they were complementary technologies, there can be little doubt that USB 2.0 specification was designed to compete with FireWire. Compaq, Hewlett-Packard, Intel, Lucent, Microsoft, NEC and Philips jointly led the development, with the aim of dramatically extending performance to the levels necessary to provide support for future classes of high performance peripherals.

At the time of the February 1999 Intel Developer Forum (IDF) the projected performance hike was of the order of 10 to 20 times over existing USB 1.1 capabilities. However, by the end of the year the results of engineering studies and test silicon indicated that that was overly conservative, and by the time the USB 2.0 was released in the spring of 2000, its specified performance was a staggering 40 times that of its predecessor.

USB 2.0 in fact defines three level of performance, with "Hi-Speed USB" referring to just the 480 Mbit/s portion of the specification and the term "USB" being used to refer to the 12 Mbit/s and 1.5 Mbit/s speeds. At 480 Mbit/s, any danger that USB would be marginalised by the rival IEEE 1394 bus appear to have been banished forever. Indeed, proponents of USB continue to maintain that the two standards address differing requirements, the aim of USB 2.0 being to provide support for the full range of PC peripherals - current and future - while IEEE 1394 specifically targets connection to audio visual consumer electronic devices such as digital camcorders, digital VCRs, DVD players and digital televisions.

While USB 1.1's data rate of 12 Mbit/s, was sufficient for many PC peripherals, especially input devices, the higher bandwidth of USB 2.0 is a major boost for external peripherals as CD/DVD burners, scanners and hard drives as well as higher functionality peripherals of the future, such as high resolution video conferencing cameras. As well as broadening the range of peripherals that may be attached to a PC, USB 2.0's increased bandwidth will also effectively increase number of devices that can be handled concurrently, up to its architectural limit.

USB 2.0 is fully backwards compatible - something that could prove a key benefit in the battle with IEEE 1394 to be the consumer interface of the future, given its already wide installed base. Existing USB peripherals will operate with no change in a USB 2.0 system. Devices, such as mice, keyboards and game pads, will not require the additional performance that USB 2.0 offers and will operate as USB 1.1 devices. Conversely, a Hi-Speed USB 2.0 peripheral plugged into a USB 1.1 system will perform at the USB 1.1 speeds.

While Windows XP did not support USB 2.0 at the time of its release in 2001 - Microsoft citing the fact that there were no production quality compatible host controllers or USB 2.0 devices available in time as the reason for this - support had been made available to OEMs and system builders by early the following year and more widely via Windows Update and the Windows XP SP1 later in 2002.

Since the USB 2.0 Specification encompasses all USB data transfer speeds - low (1.5MMbit/s), full (12Mbit/s) and high (480Mbit/s) - the USB Implementors Forum (USB-IF) sought to avoid confusion in the marketplace by introducing the terminology "Hi-Speed USB" to refer to the 480Mbit/s portion of the specification. However, despite the USB-IF's best efforts to ensure that vendors used the certified USB Logos appropriately, manufacturers were slow to switch to the new naming conventions and were often inconsistent in their use of it.

Linear Data Structures - Introduction

Data structure

A binary tree, a simple type of branching linked data structure.

In the field of computer science, a data structure is a way of storing data in a computer so that it can be used efficiently. Often a carefully chosen data structure will allow the most efficient algorithm to be used. The choice of the data structure often begins from the choice of an abstract data structure. A well-designed data structure allows a variety of critical operations to be performed, using as few resources, both execution time and memory space, as possible. Data structures are implemented using the data types, references and operations on them provided by a programming language.

Different kinds of data structures are suited to different kinds of applications, and some are highly specialized to certain tasks. For example, B-trees are particularly well-suited for implementation of databases, while routing tables rely on networks of machines to function.

In the design of many types of programs, the choice of data structures is a primary design consideration, as experience in building large systems has shown that the difficulty of implementation and the quality and performance of the final result depends heavily on choosing the best data structure. After the data structures are chosen, the algorithms to be used often become relatively obvious. Sometimes things work in the opposite direction - data structures are chosen because certain key tasks have algorithms that work best with particular data structures. In either case, the choice of appropriate data structures is crucial.

This insight has given rise to many formalised design methods and programming languages in which data structures, rather than algorithms, are the key organising factor. Most languages feature some sort of module system, allowing data structures to be safely reused in different applications by hiding their verified implementation details behind controlled interfaces. Object-oriented programming languages such as C++ and Java in particular use classes for this purpose.

Since data structures are so crucial to professional programs, many of them enjoy extensive support in standard libraries of modern programming languages and environments, such as C++'s Standard Template Library, the Java API, and the Microsoft .NET Framework.

The fundamental building blocks of most data structures are arrays, records, discriminated unions, and references. For example, the nullable reference, a reference which can be null, is a combination of references and discriminated unions, and the simplest linked data structure, the linked list, is built from records and nullable references.

There is some debate about whether data structures represent implementations or interfaces. How they are seen may be a matter of perspective. A data structure can be viewed as an interface between two functions or as an implementation of methods to access storage that is organized according to the associated data type.

Computers In Schools

You should be able to find several indispensable facts about Computers In Schools in the following paragraphs. If there's at least one fact you didn't know before, imagine the difference it might make.

I am always amazed when I take a gander at today's school systems. I mean, sure they have their flaws, but they also offer plenty of wonderful nuances. And I'm just comparing them to my high school back in the early 90s. One of the great aspects of today's learning centers involves computers. Not only do they now offer computers in schools, but they even put them in the classrooms. That's sweet if you ask me. I would have loved to have had a computer in my classroom back in elementary school. Imagine the cool learning games that could be played. Yes indeed folks, schools are sure changing.

If your Computers In Schools facts are out-of-date, how will that affect your actions and decisions? Make certain you don't let important Computers In Schools information slip by you.

What do you think about computers in schools? Do you think they are a wonderful learning tool, or a mere distraction for the students? This is a major concern for some. I was surprised after speaking with my mother who does not condone computers in schools. I could hardly grasp why she felt this way. However, she feels that knowledge should come from the texts and the teacher. Oh well, what can you do; the woman went to a country school in the 40s. I'm sure things were much different on many levels back then. You know with the whole trudging to school through the 6 foot deep snow and all. Regardless of my mother's views on computers in schools, I must still support the use of PCs and Mac for learning tools in classrooms and media centers. It just makes sense if you truly sit down and think about it. No single source is going to offer you more knowledge and information than a contemporary computer with Internet access.

Do you have PCs or Macs in your school? This is something I've noticed that varies from school to school. Although we had PCs in my University back in Oregon, my daughter has Macs in her elementary school. Each school must strike a deal with the companies or something. Regardless, they do virtually the same things in my opinion. Although Macs tend to be a little simpler to operate for some. So, when it comes down to the issue of computers in schools, I think it's safe to say that this is a prudent additive to any learning environment. To find out what computers are in your child's school, simply take a look around. That's what I did.

When word gets around about your command of Computers In Schools facts, others who need to know about Computers In Schools will start to actively seek you out.

Panda Antivirus Anti virus 2008 Review

This year, Panda offers two distinct antivirus products. To compare with other products tested and reviewed by CNET this year, we chose the Panda Antivirus 2008. A second product, Panda Antivirus plus Firewall 2008 was not reviewed. The $39.95 price for a three-user license is at the low end, which is good. However, when compared with the also economical BitDefender Antivirus 2008, Panda comes up short, lacking some features and, more importantly, similar test results. Panda is slower and is mostly unrated in independent, third-party antivirus test results. If you're looking for economy, chose BitDefender. If you're looking for the best antivirus product for 2008, we recommend Kaspersky Anti-Virus 2008, our Editors' Choice.

Setup
Panda Antivirus 2008 includes three PC licenses for $39.95. By comparison, BitDefender Antivirus offers its three-user license for $29.95. Kaspersky offers a single license at $49.95 and charges $59.95 for its three-user license. Panda Antivirus 2008 runs on Windows 2000, XP, and Vista, while Norton AntiVirus 2008 works only on XP and Vista.

After downloading the 35MB file, Panda performs an initial scan of your system, and in our case, found eight different examples of spyware. Unfortunately, Panda didn't tell us precisely what spyware it found; only that it deleted it. Later, we could find no record of this scan for reference, although we did find subsequent log files of spyware that had been removed. We prefer to have control over what is quarantined or removed from our machine, and wish Panda had provided us with more information.

Should you want to remove Panda Antivirus 2008, there is an uninstall wizard available. Upon reboot, we did not find any traces of Panda left on our machine.

Panda Antivirus 2008 includes an interface with bright, contrasting colors and basic graphics.

Interface
Compared to the interfaces found with other antivirus products, Panda Antivirus 2008 is simple, even cartoonish: bright, contrasting colors, with basic graphics; as though Fisher-Price made antivirus interfaces for kids. We were, however, pleased to find configuration options within easy reach.

During a manual scan, we were unable to open other features of the program, something we could do in other antivirus apps.

Features
Panda Antivirus 2008 includes TruPrevent, Panda's heuristic engine that proactively blocks viruses. However, it blocks only viruses. The full version of TruPrevent, which blocks other forms of malware as well, is available in the Panda Antivirus and Firewall and Panda Internet Security products.

Antiphishing protection is included with Panda Antivirus, but Panda Antivirus and Firewall and Panda Internet Security products include additional protection from malware lurking on Web pages.

Performance
Panda scored near the middle of the antivirus products in CNET Labs' performance tests. On our iTunes test, Panda was fast at 270 seconds, just 2 seconds more than our test system. On our Microsoft Office test, Panda was solidly in the middle at 1,355 seconds. In a test scanning a single folder with compressed and media files, Panda scored a fast 135 seconds, however, the default setting excludes many of the compressed files used in our test. And in terms of boot speed, Panda came in dead last at 39 seconds. To find out how we test antivirus software, see CNET Labs' How we test: Antivirus software page.

In terms of protecting your PC, we cite results from two leading independent antivirus testing organizations. Panda was not tested by AV-Comparatives.org. CheckVir.com tested Panda Internet Security 2006 and awarded it a Standard rating, meaning it was evaluated only on its ability to search for viruses, but not the removal of them.

Although we were told U.S. residents didn't have to accept this disclaimer, the notice still appears in domestic downloads of Panda Antivirus 2008.

Support
Support is extremely light for Panda Antivirus 2008. The built-in Help file lacks significant detail. The Panda Web site includes an interactive troubleshooter, which seems promising until it takes you to the weak knowledgebase section. Other antivirus apps have interactive self-diagnostics, so be careful of this terminology; Panda uses something else. On the Panda knowledgebase page, when you type in a query, the site spits back an FAQ in response. If you want to cut to the chase and see all the preanswered questions in advance, simply click Hot Topics. There is a secondary PDF document; it, too, was light on technical details. Nor could we find a user forum, chat, or telephone support section.

E-mail technical support includes a curious box that says any personal information you send to Panda becomes property of Panda and its business partners. We could not advance our query unless we agreed. When we asked our Panda representatives, they explained that users within the United States should not have seen that box, that it is a requirement only within Europe. After waiting six weeks for Panda to remove this check box, we downloaded a fresh copy of the program and found that it still included the checkbox.

The good: Panda Antivirus 2008 includes antispyware protection.

The bad: Panda Antivirus 2008 has not been reviewed by many independent antivirus test sites, making it hard to say how effective it is; it tends to be slower than the competition; support is light, with almost no documentation and a requirement that Panda own any personal information sent via e-mail technical support.

The bottom line: Panda Antivirus 2008 is slower than the competition and lacks independent, third-party antivirus test results, and thus doesn't receive our recommendation.

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Sorting Algorithms - Shell Sort

Shell sort

Shell sort is a sorting algorithm that, with its original implementation, requires O (n²) comparisons and exchanges in the worst case. A minor change given in V. Pratt's book produces an implementation with worst case performance of O(nlog² n). This is better than the O(n²) comparisons required by naive algorithms but worse than the optimal O(n log n) (see comparison sort). Although it is easy to develop an intuitive sense of how this algorithm works, it is very difficult to analyze its execution time.

Shell sort is a generalization of insertion sort, with two observations in mind:

Insertion sort is efficient if the input is "almost sorted".
Insertion sort is inefficient, on average, because it moves values just one position at a time.

Shell sort improves insertion sort by comparing elements separated by a gap of several positions. This lets an element take "bigger steps" toward its expected position. Multiple passes over the data are taken with smaller and smaller gap sizes. The last step of Shell sort is a plain insertion sort, but by then, the array of data is guaranteed to be almost sorted.

Consider a small value that is initially stored in the wrong end of the array. Using an O(n2) sort such as bubble sort or insertion sort, it will take roughly n comparisons and exchanges to move this value all the way to the other end of the array. Shell sort first moves values using giant step sizes, so a small value will move a long way towards its final position, with just a few comparisons and exchanges.

One can visualize Shellsort in the following way: arrange the list into a table and sort the columns (using an insertion sort). Repeat this process, each time with smaller number of longer columns. At the end, the table has only one column. While transforming the list into a table makes it easier to visualize, the algorithm itself does its sorting in-place (by incrementing the index by the step size, i.e. using i += step_size instead of i++).

For example, consider a list of numbers like [ 13 14 94 33 82 25 59 94 65 23 45 27 73 25 39 10 ]. If we started with a step-size of 5, we could visualize this as breaking the list of numbers into a table with 5 columns. This would look like this:

13 14 94 33 82

25 59 94 65 23

45 27 73 25 39

We then sort each column, which gives us

10 14 73 25 23

13 27 94 33 39

25 59 94 65 82

When read back as a single list of numbers, we get [ 10 14 73 25 23 13 27 94 33 39 25 59 94 65 82 45 ]. Here, the 10 which was all the way at the end, has moved all the way to the beginning. This list is then again sorted using a 3-gap sort, and then 1-gap sort (simple insertion sort).

The Shell sort is named after its inventor, Donald Shell, who published it in 1959. Some older textbooks and references call this the "Shell-Metzner" sort after Marlene Metzner Norton, but according to Metzner, "I had nothing to do with the sort, and my name should never have been attached to it."

Gap sequence

The shellsort algorithm in action

The gap sequence is an integral part of the shellsort algorithm. Any increment sequence will work, so long as the last element is 1. The algorithm begins by performing a gap insertion sort, with the gap being the first number in the gap sequence. It continues to perform a gap insertion sort for each number in the sequence, until it finishes with a gap of 1. When the gap is 1, the gap insertion sort is simply an ordinary insertion sort, guaranteeing that the final list is sorted.

The gap sequence that was originally suggested by Donald Shell was to begin with $N / 2$ and to halve the number until it reaches 1. While this sequence provides significant performance enhancements over the quadratic algorithms such as insertion sort, it can be changed slightly to further decrease the average and worst-case running times. Weiss' textbook demonstrates that this sequence allows a worst case $O (n 2)$ sort, if the data is initially in the array as (small_1, large_1, small_2, large_2, ...) - that is, the upper half of the numbers are placed, in sorted order, in the even index locations and the lower end of the numbers are placed similarly in the odd indexed locations.

Perhaps the most crucial property of Shellsort is that the elements remain k-sorted even as the gap diminishes. For instance, if a list was 5-sorted and then 3-sorted, the list is now not only 3-sorted, but both 5- and 3-sorted. If this were not true, the algorithm would undo work that it had done in previous iterations, and would not achieve such a low running time.

Depending on the choice of gap sequence, Shellsort has a proven worst-case running time of $O (n 2)$ (using Shell's increments that start with 1/2 the array size and divide by 2 each time), $O (n 3 / 2)$ (using Hibbard's increments of $2 k - 1$ ), $O (n 4 / 3)$ (using Sedgewick's increments of $9(4 i) - 9(2 i) + 1$ , or $4 i + 1 + 3(2 i) + 1$ ), or $O (n log 2 n)$ , and possibly unproven better running times. The existence of an $O (n log n)$ worst-case implementation of Shellsort remains an open research question.

Shell sort algorithm in C/C++

Shell sort is commonly used in programming languages; this is an implementation of the algorithm in C/C++ for sorting an array of integers. The increment sequence used in this example code gives an O(n2) worst-case running time.

void shell_sort(int A[], int size)

  int i, j, incrmnt, temp;

  incrmnt = size / 2;

  while (incrmnt > 0)

    for (i=incrmnt; i < size; i++)

      j = i;

      temp = A[i];

      while ((j >= incrmnt) && (A[j-incrmnt] > temp))

        A[j] = A[j - incrmnt];

        j = j - incrmnt;

      A[j] = temp;

    incrmnt /= 2;

Shell sort algorithm in Java

The Java implementation of Shell sort is as follows:

 public static void shellSort(int[] a) {

     for ( int increment = a.length / 2;

           increment > 0;

           increment = (increment == 2 ? 1 : (int) Math.round(increment / 2.2))) {

         for (int i = increment; i < a.length; i++) {

             for (int j = i; j >= increment && a[j - increment] > a[j]; j -= increment) {

                 int temp = a[j];

                 a[j] = a[j - increment];

                 a[j - increment] = temp;

For some unexplained reason, when the increment is divided by 2.2 as opposed to being continuously halved, this algorithm works about 25 to 30 percent faster on large inputs.

Basic Data Structures - Integer

Integer

In computer science, the term integer is used to refer to any data type which can represent some subset of the mathematical integers. These are also known as integral data types.

Value and representation

The value of a datum with an integral type is the mathematical integer that it corresponds to. The representation of this datum is the way the value is stored in the computer s memory. Integral types may be unsigned (capable of representing only non-negative integers) or signed (capable of representing negative integers as well).

The most common representation of a positive integer is a string of bits, using the binary numeral system. The order of the bits varies; see Endianness. The width or precision of an integral type is the number of bits in its representation. An integral type with n bits can encode 2ⁿ numbers; for example an unsigned type typically represents the non-negative values 0 through 2ⁿ−1.

There are three different ways to represent negative numbers in a binary numeral system. The most common is two s complement, which allows a signed integral type with n bits to represent numbers from −2⁽ⁿ⁻¹⁾ through 2⁽ⁿ⁻¹⁾−1. Two s complement arithmetic is convenient because there is a perfect one-to-one correspondence between representations and values, and because addition and subtraction do not need to distinguish between signed and unsigned types. The other possibilities are sign-magnitude and ones' complement. See Signed number representations for details.

Another, rather different, representation for integers is binary-coded decimal, which is still commonly used in mainframe financial applications and in databases.

Common integral data types

Bits	Name	Range	Uses
8	byte, octet	Signed: −128 to +127 Unsigned: 0 to +255	ASCII characters, C int8_t, Java byte
16	halfword, word	Signed: −32,768 to +32,767 Unsigned: 0 to +65,535	UCS-2 characters, C int16_t, Java char, Java short
32	word, doubleword, longword	Signed: −2,147,483,648 to +2,147,483,647 Unsigned: 0 to +4,294,967,295	UCS-4 characters, Truecolor with alpha, C int32_t, Java int
64	doubleword, longword, quadword	Signed: −9,223,372,036,854,775,808 to +9,223,372,036,854,775,807 Unsigned: 0 to +18,446,744,073,709,551,615	C int64_t, Java long
128		Signed: −170,141,183,460,469,231,731,687,303,715,884,105,728 to +170,141,183,460,469,231,731,687,303,715,884,105,727 Unsigned: 0 to +340,282,366,920,938,463,463,374,607,431,768,211,455	C only available as non-standard compiler-specific extension
n	n-bit integer	Signed: $- 2 n - 1$ to $2 n - 1 - 1$ Unsigned: 0 to $2 n - 1$

Different CPUs support different integral data types. Typically, hardware will support both signed and unsigned types but only a small, fixed set of widths.

The table above lists integral type widths that are supported in hardware by common processors. High level programming languages provide more possibilities. It is common to have a double width integral type that has twice as many bits as the biggest hardware-supported type. Many languages also have bit-field types (a specified number of bits, usually constrained to be less than the maximum hardware-supported width) and range types (which can represent only the integers in a specified range).

Some languages, such as Lisp, REXX and Haskell, support arbitrary precision integers (also known as infinite precision integers or bignums). Other languages which do not support this concept as a top-level construct may have libraries available to represent very large numbers using arrays of smaller variables, such as Java's BigInteger class or Perl's "bigint" package. These use as much of the computer s memory as is necessary to store the numbers; however, a computer has only a finite amount of storage, so they too can only represent a finite subset of the mathematical integers. These schemes support very large numbers, for example one kilobyte of memory could be used to store numbers up to about 2560 digits long.

A Boolean or Flag type is a type which can represent only two values: 0 and 1, usually identified with false and true respectively. This type can be stored in memory using a single bit, but is often given a full byte for convenience of addressing and speed of access.

A four-bit quantity is known as a nibble (when eating, being smaller than a bite) or nybble (being a pun on the form of the word byte). One nibble corresponds to one digit in hexadecimal and holds one digit or a sign code in binary-coded decimal.

Data type names

Bits	Signed	Java	C#	SQL92	vbScript	C
8	Yes	byte	sbyte			int8_t, signed char
16	Yes	short	short, Int16	smallint, int2	int	int16_t, int (on C89), short(on C99)
32	Yes	int	int, Int32	integer, int, int4	long	int32_t, long(on C89), int(on C99)
64	Yes	long	long, Int64	bigint, int8		int64_t, long long (on C99)
8	No		byte	tinyint, int1	byte	uint8_t, unsigned char
16	No	char	ushort, UInt16			uint16_t,
32	No		uint, UInt32			uint32_t, unsigned int(on C89), unsigned short(on C99)
64	No		ulong, UInt64			uint64_t, unsigned long long (on C99)

Note: C++ has no compiler-independent integer types with fixed bit widths.

Pointers

A pointer is often, but not always, represented by an unsigned integer of specified width. This is often, but not always, the widest integer that the hardware supports directly. The value of this integer is the memory address of whatever the pointer points to.

Bytes and octets

The term byte initially meant the smallest addressable unit of memory . In the past, 5-, 6-, 7-, 8-, and 9-bit bytes have all been used. There have also been computers that could address individual bits ( bit-addressed machine ), or that could only address 16- or 32-bit quantities ( word-addressed machine ). The term byte was usually not used at all in connection with bit- and word-addressed machines.

The term octet always refers to an 8-bit quantity. It is mostly used in the field of computer networking, where computers with different byte widths might have to communicate.

In modern usage byte almost invariably means eight bits, since all other sizes have fallen into disuse; thus byte has come to be synonymous with octet.

Words

The term word is used for a small group of bits which are handled simultaneously by processors of a particular architecture. The size of a word is thus CPU-specific. Many different word sizes have been used, including 6-, 8-, 12-, 16-, 18-, 24-, 32-, 36-, 39-, 48-, 60-, and 64-bit. Since it is architectural, the size of a word is usually set by the first CPU in a family, rather than the characteristics of a later compatible CPU. The meanings of terms derived from word, such as longword, doubleword, quadword, and halfword, also vary with the CPU and OS.

As of 2006, 32-bit word sizes are most common among general-purpose computers, with 64-bit machines used mostly for large installations. Embedded processors with 8- and 16-bit word size are still common. The 36-bit word length was common in the early days of computers, but word sizes that are not a multiple of 8 have vanished along with non-8-bit bytes.

Character (computing)

In computer and machine-based telecommunications terminology, a character is a unit of information that roughly corresponds to a grapheme or a grapheme-like unit or symbol, such as in an alphabet or syllabary in the written form of a natural language.

An example of a character is a letter, numeral, or punctuation mark. The concept also includes control characters, which do not correspond to natural language symbols but to other bits of information used to process texts of the language, such as control characters like carriage return or tab, as well as instructions to printers or other devices that display such texts.

Character encoding

Computers and communication equipment represent characters using a character encoding that assigns each character to something an integer quantity represented by a sequence of bits, typically that can be stored or transmitted through a network. The most common encoding is ASCII, though the more versatile Unicode is quickly becoming popular. While most character encodings map characters to numbers and/or bit sequences, Morse code instead represents characters using a series of electrical impulses of varying length.

Terminology

Historically, the term character has been widely used by industry professionals to refer to an encoded character (often only as exposed via a programming language's API). Likewise, character set has been widely used to refer to a specific repertoire of abstract characters that have been mapped to specific bit sequences. With the advent of Unicode and bit-agnostic encoding forms, more precise terminology is increasingly favored.

It is important, in some contexts, to make the distinction that a character is a unit of information, and thus does not imply any particular visual manifestation. For example, the Hebrew letter Aleph ("א") is often used by mathematicians to denote certain kinds of infinity, but it is also used in ordinary Hebrew text. In Unicode, these two uses are different characters and are signified by two different codes, though they may be rendered identically. Conversely, the Chinese logogram for water ("水") may have a slightly different appearance in Japanese texts than it does in Chinese texts, and local typefaces may reflect this. But they nonetheless represent the same information, are considered the same character, and share the same Unicode code point.

The term glyph is used to describe a particular physical appearance of a character. Many computer fonts consist of glyphs that are indexed by the Unicode code point of the character that each glyph represents.

The definition of character, or abstract character, is mutually defined by The Unicode Standard and ISO/IEC 10646 as "a member of a set of elements used for the organisation, control, or representation of data." Unicode's definition supplements this with explanatory notes that encourage the reader to differentiate between characters, graphemes, and glyphs, among other things. The standards also differentiate between these abstract characters and coded characters or encoded characters that have been paired with numeric codes that facilitate their representation in computers.

Basic Data Structures - String

String

In computer programming and formal language theory, (and other branches of mathematics), a string is an ordered sequence of symbols. These symbols are chosen from a predetermined set.

In programming, when stored in memory each symbol is represented using a numeric value. A variable declared to have a string datatype usually causes storage to be allocated in memory that is capable of holding some predetermined number of symbols. When it appears in source code a string is known as a string literal and has a representation that denotes it as such. Sometimes the term binary string is used to refer to an arbitrary sequence of bits.

Formal theory

Let Σ be an alphabet, a non-empty finite set. El ements of Σ are called symbols or characters. A string (or word) over Σ is any finite sequence of characters from Σ. For example, if Σ = {0, 1}, then 0101 is a string over Σ.

The length of a string is the number of characters in the string (the length of the sequence) and can be any non-negative integer. The empty string is the unique string over Σ of length 0, and is denoted ε or λ.

The set of all strings over Σ of length n is denoted Σⁿ. For example, if Σ = {0, 1}, then Σ² = {00, 01, 10, 11}. Note that Σ⁰ = {ε} for any alphabet Σ.

The set of all strings over Σ of any length is the Kleene closure of Σ and is denoted Σ*. In terms of Σⁿ, . For example, if Σ = {0, 1}, Σ* = {ε, 0, 1, 00, 01, 10, 11, 000, 001, 010, 011, }. Although Σ* itself is countably infinite, all elements of Σ* have finite length.

A set of strings over Σ (i.e. any subset of Σ*) is called a formal language over Σ. For example, if Σ = {0, 1}, the of the set of strings with an even number of zeros ({ε, 1, 00, 11, 001, 010, 100, 111, 0000, 0011, 0101, 0110, 1001, 1010, 1100, 1111, }) is a formal language over Σ*.

Concatenation and substrings

Concatenation is an important binary operation o n Σ*. For any two strings s and t in Σ*, their concatenation is defined as the sequence of characters in s followed by the sequence of characters in t, and is denoted st. For example, if Σ = {a, b, , z}, s = bear, and t = hug, then st = bearhug and ts = hugbear.

String concatenation is an associative, but non-commutative operation. The empty string serves as the identity element; for any string s, εs = sε = s. Therefore, the set Σ* and the concatenation operation form a monoid, the free monoid generated by Σ. In addition, the length function defines a monoid homomorphism from Σ* to the non-negative integers.

A string s is said to be a substring or factor of t if there exist (possibly empty) strings u and v such that t = usv. The relation "is a substring of" defines a partial order on Σ*, the least element of which is the empty string.

Lexicographical ordering

It is often necessary to define an ordering on the set of strings. If the alphabet Σ has a total order (cf. alphabetical order) one can define a total order on Σ* called lexicographical order. Note that since Σ is finite, it is always possible to define a well ordering on Σ and thus on Σ*. For example, of Σ = {0, 1} and 0 < 1, then the lexicographical ordering of Σ* is ε < 0 < 00 < 000 < < 011 < 0110 < < 01111 < < 1 < 10 < 100 < < 101 < < 111

String operations

A number of additional operations on strings commonly occur in the formal theory. These are given in the article on string operations.

String datatypes

A string datatype is a datatype modeled on the idea of a formal string. Strings are such an important and useful datatype that they are implemented in nearly every programming language. In some languages they are available as primitive types and in others as composite types. The syntax of most high-level programming languages allows for a string, usually quoted in some way, to represent an instance of a string datatype; such a meta-string is called a literal or string literal.

String length

Although formal strings can have an arbitrary (but finite) length, the length of strings in real languages is often constrained to an artificial maximum. In general, there are two types of string datatypes: fixed length strings which have a fixed maximum length and which use the same amount of memory whether this maximum is reached or not, and variable length strings whose length is not arbitrarily fixed and which use varying amounts of memory depending on their actual size. Most strings in modern programming languages are variable length strings. Despite the name, even variable length strings are limited in length; although, generally, the limit depends only on the amount of memory available.

Character encoding

Historically, string datatypes allocated one byte per character, and although the exact character set varied by region, character encodings were similar enough that programmers could generally get away with ignoring this groups of character sets used by the same system in different regions either had a character in the same place, or did not have it at all. These character sets were typically based on ASCII or EBCDIC.

Logographic languages such as Chinese, Japanese, and Korean (known collectively as CJK) need far more than 256 characters (the limit of a one-byte-per-character encoding) for reasonable representation. The normal solutions involved keeping single-byte representations for ASCII and using two-byte representations for CJK ideographs. Use of these with existing code led to problems with matching and cutting of strings, the severity of which depended on how the character encoding was designed. Some encodings such as the EUC family guarantee that a byte value in the ASCII range will only represent that ASCII character, making the encoding safe for systems that use those characters as field separators. Other encodings such as ISO-2022 and Shift-JIS do not make such guarantees, making matching on byte codes unsafe. Another issue is that if the beginning of a string is deleted, important instructions for the decoder or information on position in a multibyte sequence may be lost. Another is that if strings are joined together (especially after having their ends truncated by code not aware of the encoding), the first string may not leave the encoder in a state suitable for dealing with the second string.

Unicode has complicated the picture somewhat. Most languages have a datatype for Unicode strings (usually UTF-16 as it was usually added before Unicode supplemental planes were introduced). Converting between Unicode and local encodings requires an understanding of the local encoding, which may be problematic for existing systems where strings of various encodings are being transmitted together with no real marking as to what encoding they are in.

Implementations

Some languages like C++ implement strings as templates that can be used with any primitive type, but this is the exception, not the rule.

If an object-oriented language represents strings as objects, they are called mutable if the value can change at runtime and immutable if the value is frozen after creation. For example, Ruby has mutable strings, while Python's strin gs are immutable.

Representations

Representations of strings depend heavily on the choice of character repertoire and the method of character encoding. Older string implementations were designed to work with repertoire and encoding defined by ASCII, or more recent extensions like the ISO 8859 series. Modern implementations often use the extensive repertoire defined by Unicode along with a variety of complex encodings such as UTF-8 and UTF-16.

Most string implementations are very similar to variable-length arrays with the entries storing the character codes of corresponding characters. The principal difference is that, with certain encodings, a single logical character may take up more than one entry in the array. This happens for example with UTF-8, where single characters can take anywhere from one to four bytes. In these cases, the logical length of the string differs from the logical length of the array.

The length of a string can be stored implicitly by using a special terminating character; often this is the null character having value zero, a convention used and perpetuated by the popular C programming language. Hence, this representation is commonly referred to as C string. The length of a string can also be stored explicitly, for example by prefixing the string with byte value a convention used in Pascal; consequently some people call it a P-string.

In terminated strings, the terminating code is not an allowable character in any string.

Here is an example of a null-terminated string stored in a 10-byte buffer, along with its ASCII representation:

F	R	A	N	K	NUL	k	e	f	w
46	52	41	4E	4B	00	6B	65	66	77

The length of a string in the above example is 5 characters, but it occupies 6 bytes. Characters after the terminator do not form part of the representation; they may be either part of another string or just garbage. (Strings of this form are sometimes called ASCIZ strings, after the original assembly language dire ctive used to declare them.)

Here is the equivalent (old style) Pascal string stored in a 10-byte buffer, along with its ASCII representation:

length	F	R	A	N	K	k	f	f	w
05	46	52	41	4E	4B	6B	66	66	77

While these representations are common, others are possible. Using ropes makes certain string operations, such as insertions, deletions, and concatenations more efficient.

Vectors

While character strings are very common uses of strings, a string in computer science may refer generically to any vector of homogenously typed data. A string of bits or bytes, for example, may be used to represent data retrieved from a communications medium. This data may or may not be represented by a string-specific datatype, depending on the needs of the application, the desire of the programmer, and the capabilities of the programming language being used.

String processing algorithms

There are many algorithms for processing strings, each with various trade-offs. Some categories of algorithms include

string searching algorithms for finding a given substring or pattern;

string manipulation algorithms;

sorting algorithms;

regular expression algorithms; and

parsing a string.

Advanced string algorithms often employ complex mechanisms and data structures, among them suffix trees and finite state machines.

Character string oriented languages and utilities

Character strings are such a useful datatype that several languages have been designed in order to make string processing applications easy to write. Examples include the following languages:

awk

Icon

MUMPS

Perl

Rexx

Ruby

sed

SNOBOL

Tcl

Many UNIX utilities perform simple string manipulations and can be used to easily program some powerful string processing algorithms. Files and finite streams may be viewed as strings.

Several string libraries for the C and C++ programming languages do exist which add greater functionality for string processing in those languages:

The Better String Library

The Vstr String Library

Perl Compatible Regular Expressions

Comparison page for C/C++ string libraries

Some APIs like Multimedia Control Interface, embedded SQL or printf use strings to hold commands that will be interpreted.

Recent scripting programming languages, including Perl, Python, Ruby, and Tcl employ regular expressions to facilitate text operations.

Character string functions

String functions are used to manipulate a string or change or edit the contents of a string. They also are used to query information about a string. They are usually used within the context of a computer programming language.

The most basic example of a string function is the length(string) function. This function returns the length of a string (not counting the null terminator or any other of the string's internal structural information) and does not change the string.

eg. length("hello world") would return 11.

There are many string functions which exist in other languages with similar or exactly the same syntax or parameters. For example in many languages the length function is usually represented as len(string). Even though string functions are very useful to a computer programmer, a computer programmer using these functions should be mindful that a string function in one language could in another language behave differently or have a similar or completely different function name, parameters, syntax and outcomes.

Evolution of Mobile and wireless

Mobile and wireless have known a success that is beyond the most optimistic initial expectations. In some countries, namely European ones, the penetration of mobile communications is around 100%, which means that virtually everyone capable of using a mobile phone has (at least) one. How did we get here? What were the reasons for this huge success? These questions have been discussed over and over, and are not addressed here. Nevertheless, one thing is certain: in the past, someone, somewhere, had a vision that we all could use a single communications device under the well-known motto anytime, anywhere .

In the .rst years of 1980s, Europe was at the very beginning of the commercial exploration of mobile communications services (exclusively voice at the time), almost each country presenting its own system (the so-called 1st Generation (1G)). Things taken for granted nowadays, like roaming, were not possible, in most of cases not even between countries using the same system. The panorama was very much different from the one we live in today.

Then, as a consequence of the previously mentioned vision, a pan-European mobile communications system was developed, enabling European citizens to move around the common European space, communicating using their mobile phones. Hence, the Global System for Mobile Communications (GSM) was born (de.ning the commonly accepted concept of 2nd Generation (2G)), the rest of the success story is well known, and will not be told here.

Universal Mobile Telecommunications System (UMTS), the successor to GSM in Europe (usually designated by 3rd Generation (3G)), found itself being different from its predecessor by offering users a set of services that were not (initially) foreseen for GSM, i.e. multimedia in general (in particular, ranging from video-telephony to Internet access). At the time UMTS was being outlined, the vision was to give mobile users, already used to making calls with their mobile phones, the possibility to use services on their phone that would contribute to an increase in their means of communication. Since then the technical evolution of mobile and wireless communication systems has witnessed the appearance of a panoply of systems, encompassing Digital Video Broadcasting (DVB), High Performance Radio Local Area Network (HIPERLAN) and Bluetooth, to mention only a few within European initiatives (some of which were not actually implemented into commercial products). Outside Europe, many other systems were developed, and made a path parallel to the European ones. For the future, mobile and wireless applications and services are likely to become pervasive, with a wide spread use of devices. Computation and communication capabilities are being integrated in a large variety of devices, from simple sensors and interactive appliances (cards, rings, eyeglasses, etc.) via pocket and lap-sized devices to wall or table screen working areas. The technology will undergo a transformation, from an expensive, highly visible, hi-tech technology as in early mobile phones, over the current situation where (almost) everyone owns a mobile phone, to a disappearing technology that is present everywhere and taken for granted. Since the current cellular mobile approach, with its excellent mobility management and coverage properties, does not scale everywhere into large bandwidths, the result will be heterogeneous infrastructures with moderate bandwidth wide area coverage, and a local high bandwidth wireless coverage. Moreover, there is clearly the need to invent new access techniques and network architectures, so that future use of mobile and wireless communications can be made in an effective way. Such a vision challenges many of the current paradigms in mobile and wireless communications.

Currently, there is lack of a unique concept for the incoming 4th Generation (4G). A new vision should be set; as in the past, one can almost say that the probability of increased success can be measured by the way this vision creates a disruption with the existing networks and systems. On the one hand, one cannot aim at farfetched objectives, which are very unlikely to be reached within an acceptable timeframe. On the other, having as an objective something similar to the Olympic Games motto ( Citius, Altius, Fortius , meaning Faster, Higher, Stronger ), applied to current systems and techniques (i.e. more of the same, but just better), is too shortterm.

The old vision of anywhere, anytime could easily be replaced by, any network, any device, any content . Basically, this vision carries many implications, some of which are discussed in what follows. It cannot be expected that users make a decision on the network to be used on their common use of the system; hence, the adaptability of networks to the type of users and information they are communicating will be an essential feature. Users will be capable of communicating how, where and whenever they want to, but it also implies that the complexity of networks and systems should be concealed from them, even if they are using more than one system and/or network simultaneously to carry the information.

The use of the system will tend to be independent of the device. One can imagine that users will just carry a kind of Radio Frequency Subscriber Identity Module (RF SIM), i.e. simply a small card that carries all their information and that communicates via RF with all the devices available in its range. This will enable users to take advantage of many types of devices, using those that are more appropriate for a given service or location. The more important role of Personal Area Networks (PANs) and ad hoc networking will set new borders. Sensor networks will become increasingly important, and the number of devices people carry with them (knowingly or unknowingly) will increase. Machine-to-machine communications will de.nitely need to be taken into account, because they help in increasing system intelligence and in concealing technology from users. Users will be provided with and have access to content and information they want in a useful way, namely transmission speed. In the future, much of the user information may indeed be local, as opposed to information that does not depend on location. Moreover, peer-to-peer communications will play a key role.

Sometimes the user requests the information, i.e. user access to information , while other times it is the information that accesses the user , based on the user s personal or family pro.le. Access to the vast range of information and content has to consider a user s techno-ability , and must be simple and intuitive to use. The success of such vision depends very much on the simplicity of access and use of services and operation of devices.

Content clari.es that the game is no longer played only with voice, but rather it extends far beyond that, not only enabling the myriad of services and applications that everyone talks about these days, but also certainly including others that have not yet been foreseen. A future vision cannot be complete without the de.nition of the future application scenarios and users. A good starting point from which one should draw trends is to look at users as our children/grand children who will be the active population in 15 20 years time. Moreover, content needs to be meaningful, since, on the one hand, non-desired information (e.g. advertisement, spam, virus, etc.) and privacy are proving problematic in today s communications, as is evident in computing (e.g. e-mail, and intrusive and destructive Internet access); on the other, it also means that .ltering of information is very important, so that users get what they really want.

But there is the need to stretch the science of mobile and wireless communications beyond radio and computer science into new areas of knowledge. Taking the main priorities that are identi.ed these days for research and development, one can identify links with them: biology (e.g. use of biometrics for user identi.cation), medicine (e.g. measurement of the health state and transmission of an alarm in case of a problem), psychology (e.g. sensing the mood and state of mind of the user), sociology (e.g. interaction with other compatible users), nano-technologies (incorporation of circuitry/terminals in common use objects, such as spectacles), materials (e.g. cooperation with the clothing industry for the use of jackets for virtual reality), transport (e.g. placing terminals in cars), environment (e.g. decreasing electromagnetic pollution ), energy (e.g. expanding the lifetime of the batteries), among others. Finally, the information should be multisensory making use of all .ve human basic senses. Clearly, the realisation of the future vision of mobile and wireless communications demands multidisciplinary research and development, crossing the boundaries of the above sciences and different industries.

Many steps are required to make this vision a reality, and clearly from the establishment of this macroscopic vision, a number of tasks and challenges need to be identi.ed and solved at the microscopic scale. The work performed in COST Action 273 Towards Mobile Broadband Multimedia Networks Research (COST 273) intended to give small contributions at the latter scale.

Memory - part 1

MEMORY

The system memory is the place where the computer holds current programs and data that are in use, and, because of the demands made by increasingly powerful software, system memory requirements have been accelerating at an alarming pace over the last few years. The result is that modern computers have significantly more memory than the first PCs of the early 1980s, and this has had an effect on development of the PC's architecture. Storing and retrieving data from a large block of memory is more time-consuming than from a small block. With a large amount of memory, the difference in time between a register access and a memory access is very great, and this has resulted in extra layers of "cache" in the storage hierarchy.

When it comes to access speed, processors are currently outstripping memory chips by an ever-increasing margin. This means that processors are increasingly having to wait for data going in and out of main memory. One solution is to use "cache memory" between the main memory and the processor, and use clever electronics to ensure that the data the processor needs next is already in cache.

L1 cache

The Level 1 cache, or primary cache, is on the CPU and is used for temporary storage of instructions and data organised in blocks of 32 bytes. Primary cache is the fastest form of storage. Because it's built in to the chip with a zero wait-state (delay) interface to the processor's execution unit, it is limited in size.

Level 1 cache is implemented using Static RAM (SRAM) and until recently was traditionally 16KB in size. SRAM uses two transistors per bit and can hold data without external assistance, for as long as power is supplied to the circuit. The second transistor controls the output of the first: a circuit known as a "flip-flop" - so-called because it has two stable states which it can flip between. This is contrasted to dynamic RAM (DRAM), which must be refreshed many times per second in order to hold its data contents.

SRAM is manufactured in a way rather similar to how processors are: highly integrated transistor patterns photo-etched into silicon. Each SRAM bit is comprised of between four and six transistors, which is why SRAM takes up much more space compared to DRAM, which uses only one (plus a capacitor). This, plus the fact that SRAM is also several times the cost of DRAM, explains why it is not used more extensively in PC systems.

Intel's P55 MMX processor, launched at the start of 1997, was noteworthy for the increase in size of its Level 1 cache to 32KB. The AMD K6 and Cyrix M2 chips launched later that year upped the ante further by providing Level 1 caches of 64KB.

The control logic of the primary cache keeps the most frequently used data and code in the cache and updates external memory only when the CPU hands over control to other bus masters, or during direct memory access by peripherals such as floppy drives and sound cards.

Pentium chipsets such as the Triton FX (and later) support a "write back" cache rather than a "write through" cache. Write through happens when a processor writes data simultaneously into cache and into main memory (to assure coherency). Write back occurs when the processor writes to the cache and then proceeds to the next instruction. The cache holds the write-back data and writes it into main memory when that data line in cache is to be replaced. Write back offers about 10% higher performance than write-through, but cache that has this function is more costly. A third type of write mode, write through with buffer, gives similar performance to write back.

Computer Motherboard Guide

The heart of any computer is the motherboard. It is that big board inside the computer that everything is connected to. It performs the role of traffic lights and policemen, directing flows of information to where they are needed, when they are needed.

Choosing the right motherboard does not have to be a huge issue, even though there is a lot to consider. I will start off with the most major parts and move onto the the things that are less important or non-essential.

Firstly is the socket type.

The socket is the place where the processor (CPU) connects to the motherboard. There is no compatiblility between sockets, so it has to be the right one. The socket connection needs to match the connection of the processor you have or the one you intend to buy for the computer.

Most older Intel Pentium 4s utilise socket 478. Newer ones use socket 775. AMD chips utilised socket A for a long time, but now the AMD Athlon 64 series and Semprons use socket 939. Just check with someone as to what yours or your intended one will have.

Your choice of chip will have a lot to do with your needs, but choosing one with an up to date socket type will ensure slightly longer motherboard life as you can upgrade the chip for a while.

Second is the memory type

DDR is the RAM of choice for most systems, but some newer systems, which includes all Pentiums with socket 775 use DDR2. These two kinds are not interchangable and have a different number of pins. Both DDR and DDR2 come in different speed ratings measured in MHz. DDR has a usual 400MHz denoted as DDR400 or PC3200, while DDR2 can go a little higher and comes in slightly faster speeds. Just make it match what the board needs.

Third is expansion slots

The expansion slots are the places where you put extra cards onto the motherboard, like graphics cards, extra sound card or a wireless internet card. The old standard is a PCI slot and these are appropriate for most expansion cards, excepts new graphics cards.

The most simple of graphics cards are sometimes available for PCI slots, but not too many. More common are AGP cards and the newer PCI express (PCIe) cards. AGP slots come in speed variants up to 8x, make sure the slot matches your card. PCI and PCIe are incompatible, so don't be confused by that. The PCIe slots are much longer and have a securing latch. If you want an SLI graphics card setup with two PCIe cards with SLI attached together, make sure the motherboard specifically states that it supports SLI.

Fourth is hard drive and optical drive connections

Two kinds are available, IDE and SATA, IDE is older with a thick cable and SATA is newer with a thinner cable. SATA capability is usually an add-on, you can see a dedicated chip on the motherboard. IDE is being phased out, but is still used for many drives and all optical devices like DVD and CD drives. IDE has speeds of ATA66, ATA100 and ATA133, SATA has speeds of 150Mbps and 300Mbps the latter sometimes referred to as SATA2. Make sure your board supports as much or more than you intend to install.

Fifth is the extras

The number of extras available on motherboard has increased greatly and so has the quality of the extras. Things to be expected are USB 2.0, a sound card and network slot. Other things which it may or may not have are firewire and extra USB slots.

So with all that in mind you should be in good stead to make a good decision on your purchase. Happy shopping.

Roundup
Socket type - A, 478, 775, 939
Memory (RAM) - DDR, DDR2
Expansion slots - PCI and one of AGP or PCIe
ATA - ATA66, 100 or 133. SATA or SATA2
Extras - USB, network and sound card (expected), firewire, extra USB, extra SATA slots (optional but becoming more common)

Interfaces - part 10

SSA

Today's huge databases and data intensive applications demand incredible amounts of storage, and transferring massive blocks of information requires technology that is robust, reliable and scaleable. Serial Storage Architecture (SSA) is an IBM-developed interface for connecting storage devices, storage subsystems, servers and workstations in mission-critical PC server applications. However, by the start of 1999 it had failed to win major support, and appeared likely to lose out to the rival Fibre Channel standard.

SSA provides data protection for critical applications by helping to ensure that a single cable failure will not prevent access to data. All the components in a typical SSA subsystem are connected by bi-directional cabling. Data sent from the adapter can travel in either direction around the loop to its destination. SSA detects interruptions in the loop and automatically reconfigures the system to help maintain connection while a link is restored.

Up to 192 hot-swappable hard disk drives can be supported per system. Drives are available in 2.25 and 4.51GB capacities, and particular drives can be designated for use by an array in the event of hardware failure. Up to 32 separate RAID arrays can be supported per adapter, and arrays can be mirrored across servers to provide cost-effective protection for critical applications. Furthermore, arrays can be sited up to 25 metres apart - connected by thin, low-cost copper cables - allowing subsystems to be located in secure, convenient locations, far from the server itself.

With its inherent resiliency and ease of use, SSA is being increasingly deployed in server/RAID environments, where it is capable of providing for up to 80 MBps of data throughput, with sustained data rates as high as 60 MBps in non-RAID mode and 35 MBps in RAID mode.

Input/output standards

Nearly two decades on, many peripheral devices are still connected into the same serial ports and parallel ports that were present on the very first commercial, and with the exception of the Plug-and-Play standards created as part of Windows 95, the PC's "I/O technology" has changed very little since its invention in 1981. Whilst they may have been adequate for the throughputs required by the peripherals of the day, by the late 1990s the PC's serial and parallel ports fell short of users' needs in a number of important areas:

Throughput: Serial ports max out at 115.2 Kbit/s, parallel ports (depending on type) at around 500 Kbit/s, but devices such as digital video cameras require vastly more bandwidth
Ease of use: Connecting devices to legacy ports can be fiddly and messy, especially daisy-chaining parallel port devices through pass-through ports. And the ports are always inconveniently located at the rear of the PC
Hardware resources: Each port requires its own interrupt request line (IRQ). A PC has a total of 16 IRQ lines, most of which are already spoken for. Some PCs have as few as five free IRQs before peripherals are installed
Limited number of ports: Most PCs have a pair of COM ports and one parallel port. More COM ports and parallel ports can be added, but at the cost of precious IRQs.

In recent years the field of input/output technology has become one of the most exciting and dynamic areas of innovation in desktop computing today and two emerging serial data standards are about to revolutionise the way that peripheral devices are connected and take the concept of Plug-and-Play to new heights.

They also promise to eliminate much of the fuss and bother involved in connecting devices to computers, including all the spare parts and tangled wires that were so common in the PCs of the past. With these new standards, it will be possible for any user to connect a nearly limitless set of devices to the computer in just a few seconds without the requirement of technical knowledge.

CPU Technology - part 1

MOBILE CPU TECHNOLOGY

No area of personal computing has changed more rapidly than portable technology. With software programs getting bigger all the time, and portable PCs being used for a greater variety of applications, manufacturers have had to had their work cut out attempting to match the level of functionality of a desktop PC in a package that can be used on the road. This has led to a number of rapid advancements in both size and power and by mid-1998 the various mobile computing technologies had reached a level where it was possible to buy a portable computer that was as fast as a desktop machine and yet capable of being used in the absence of a mains electricity supply for over five hours.

In 2003 mobile processor technology took a huge step forward with the release of Intel's Pentium M chip, formerly codenamed "Banias". This was fundamentally different from previous Intel notebook chips, which had hitherto been based on a chip architecture that had been designed for desktop PCs. The Pentium M chips were specifically designed to reduce power consumption, rather than for raw performance. Such was their level of success that in early 2006, the NetBurst platform was succeeded by a microarchitecture that was directly based on the Pentium M, and one that Intel planned to deploy in all market sectors - mobile, desktop and server - going forward.

In mid-1995 Intel's processor of choice for notebook PCs was the 75MHz version. This was available in a special thin-film package - the Tape Carrier Package (TCP) - designed to ease heat dissipation in the close confines of a notebook. It also incorporated Voltage Reduction Technology which allowed the processor to "talk" to industry standard 3.3 volt components, while its inner core - operating at 2.9 volts - consumed less power to promote a longer battery life. In combination, these features allowed system manufacturers to offer high-performance, feature-rich notebook computers with extended battery lives. Speeds were gradually increased until they reached 150MHz in the summer of 1996.

Mobile MMX

In January 1997 the first mobile Pentiums with MMX technology appeared, clocked at 150MHz and 166MHz. Initially these were built on Intel's enhanced 0.35-micron CMOS process technology with the processor's input and output pins operating at 3.3 volts for compatibility with other components while its inner core operated at 2.8 volts. The lower core voltage enabled systems to operate within efficient thermal ranges - the maximum power dissipation being 17 watts. Faster MMX CPUs were released at intervals thereafter, finally topping out at 266MHz at the start of 1998. The autumn of the previous year had seen a couple of important milestones in the development of notebook computing.

In September 1997 two high-performance mobile Pentium MMX processors that consumed up to 50% less power than previous generation mobile processors were introduced. The new 200MHz and 233MHz "Tillamook" CPUs were the first products manufactured using Intel's advanced 0.25-micron process technology. The combined effect of this and the new CPU's significantly reduced power consumption, for the first time, took notebook processors up to the same level as desktop chips.

A few weeks later Intel announced a 120MHz mobile Pentium MMX for mini-notebook PCs - an important emerging category of mobile PCs that offered small size, light weight and fully compatible, fully functional notebook computing. Manufactured using Intel's 0.35-micron process technology, the new 120MHz processor operated at an internal voltage of 2.2 volts and consumed 4.2 watts of power. The new CPU's low power consumption coupled with MMX technology provided mini-notebook PC users with the performance and functionality to effectively run business and communication applications "on the road".

Basic Data Structures - Union

Union (computer science)

In computer science, a union is a data structure that stores one of several types of data at a single location. There are only two safe ways of accessing a union object. One is to always read the field of a union most recently assigned; tagged unions enforce this restriction. The other is to only access functionality common to all types in the union. For example, if the fields are all subtypes of a common supertype, then it is always legal to perform operations on the union object that one can perform on the supertype.

The remainder of this article will refer strictly to primitive untagged unions, as opposed to tagged unions.

Because of the limitations of their use, untagged unions are generally only provided in untyped languages or in an unsafe way (as in C). They have the advantage over simple tagged unions of not requiring space to store the tag. Most type inference algorithms cannot cope with untagged union types.

The name "union" stems from the type's formal definition. If one sees a type as the set of all values that type can take on, a union type is simply the mathematical union of its constituting types, since it can take on any value any of its fields can. Also, because a mathematical union discards duplicates, if more than one field of the union can take on a single common value, it is impossible to tell from the value alone which field was last written.

Unions in various programming languages

C/C++

In C and C++, untagged unions are expressed nearly exactly like structures (structs), except that each data member begins at the same location in memory. The data members, as in structures, need not be primitive values, and in fact may be structures or even other unions. However, C++ does not allow for a data member to be any type that has "a non-trivial constructor, a non-trivial copy constructor, a non-trivial destructor, or a non-trivial copy assignment operator." In particular, it is impossible to have the standard C++ string as a member of an union. The union object occupies as much space as the largest member, whereas structures require space equal to at least the sum of the size of its members. This gain in space efficiency, while valuable in certain circumstances, comes at a great cost of safety: the program logic must ensure that it only reads the field most recently written along all possible execution paths.

The primary usefulness of a union is to conserve space, since it provides a way of letting many different types be stored in the same space. Unions also provide crude polymorphism. However, there is no checking of types, so it is up to the programmer to be sure that the proper fields are accessed in different contexts. The relevant field of a union variable is typically determined by the state of other variables, possibly in an enclosing struct.

One common C programming idiom uses unions to perform what C++ calls a reinterpret_cast, by assigning to one field of a union and reading from another, as is done in code which depends on the raw representation of the values. This is not, however, a safe use of unions in general, and is forbidden by the C language standard.

Note that the safer tagged unions can be constructed from untagged unions (see tagged union). The safe C dialect Cyclone encourages the preference of tagged unions to untagged.

Structure and union specifiers have the same form. [ . . . ] The size of a union is sufficient to contain the largest of its members. The value of at most one of the members can be stored in a union object at any time. A pointer to a union object, suitably converted, points to each of its members (or if a member is a bit-field, then to the unit in which it resides), and vice versa.

- ANSI/ISO 9899:1990 (the ANSI C standard), section 6.5.2.1

Tagged union

In computer science, a tagged union, also called a variant, variant record, discriminated union, or disjoint union, is a data structure used to hold a value that could take on several different, but fixed types. Only one of the types can be in use at any one time, and a tag field explicitly indicates which one is in use. It can be thought of as a type which has several "cases," each of which should be handled correctly when that type is manipulated. Like ordinary unions, tagged unions can save storage by overlapping storage areas for each type, since only one is in use at a time.

Tagged unions are most important in functional languages such as ML and Haskell, where they are called datatypes (see algebraic data type) and the compiler is able to verify that all cases of a tagged union are always handled, avoiding many types of errors. They can, however, be constructed in nearly any language, and are much safer than untagged unions, often simply called unions, which are similar but do not explicitly keep track of which member of the union is currently in use.

Tagged unions are often accompanied by the concept of a constructor, which is similar but not the same as a constructor for a class. Constructors produce a tagged union value, given the initial tag value and a value of the corresponding type.

Mathematically, tagged unions correspond to disjoint or discriminated unions, usually written using +. Given an element of a disjoint union A + B, it is possible to determine whether it came from A or B. If an element lies in both, there will be two effectively distinct copies of the value in A + B, one from A and one from B.

In type theory, a tagged union is called a sum type. Notations vary, but usually the sum type A + B comes with two introduction forms and . The elimination form is case analysis: if $e$ has type $A + B$ and $e 1$ and $e 2$ have type $τ$ under the assumptions $x : A$ and $y : B$ respectively, then the term has type $τ$ . The sum type corresponds to logical disjunction under the Curry-Howard correspondence.

Advantages and disadvantages

The primary advantage of a tagged union over an untagged union is that all accesses are safe, and the compiler can even check that all cases are handled. Untagged unions depend on program logic to correctly identify the currently active field, which may result in strange behavior and hard-to-find bugs if that logic fails.

The primary advantage of a tagged union over a simple record containing a field for each type is that it saves storage by overlapping storage for all the types. Some implementations reserve enough storage for the largest type, while others dynamically adjust the size of a tagged union value as needed. When the value is immutable, or cannot be changed, it is simple to allocate just as much storage as is needed.

The main disadvantage of tagged unions is that the tag occupies space. Since there are usually a small number of alternatives, the tag can often be squeezed into 2 or 3 bits wherever space can be found, but sometimes even these bits are not available. In this case, a helpful alternative may be folded or encoded tags, where the tag value is dynamically computed from the contents of the union field. The most common examples of this are the use of reserved values, where, for example, a function returning a positive number may return -1 to indicate failure. Another common example is the tagged pointer.

Sometimes, untagged unions are used to perform bit-level conversions between types, called reinterpret casts in C++. Tagged unions are not intended for this purpose; typically a new value is assigned whenever the tag is changed.

Many languages support, to some extent, a universal data type, which is a type that includes every value of every other type, and often a way is provided to test the actual type of a value of the universal type. These are sometimes referred to as variants. While universal data types are comparable to tagged unions in their formal definition, typical tagged unions include a relatively small number of cases, and these cases form different ways of expressing a single coherent concept, such as a data structure node or instruction. Also, there is an expectation that every possible case of a tagged union will be dealt with when it is used. The values of a universal data type are not related and there is no feasible way to deal with them all.

Examples

Say we wanted to build a binary tree of integers. In ML, we would do this by creating a datatype like this:

datatype tree = Leaf

              | Node of (int * tree * tree)

This is a tagged union with two cases: one, the leaf, is used to terminate a path of the tree, and functions much like a null value would in imperative languages. The other branch holds a node, which contains an integer and a left and right subtree. Leaf and Node are the constructors, which enable us to actually produce a particular tree, such as:

Node(5, Node(1,Leaf,Leaf), Node(3, Leaf, Node(4, Leaf, Leaf)))

which corresponds to this tree:

Now we can easily write a typesafe function that, say, counts the number of nodes in the tree:

fun countNodes(Leaf) = 0

  | countNodes(Node(int,left,right)) =

1 + countNodes(left) + countNodes(right)

Time line of language support

1960s

In Algol 68, tagged unions are called united modes, the tag is implicit, and the case construct is used to determine which field is tagged:

 mode node = union (real, int, compl, string);

Usage example for union case of node:

 node n := "1234";

 case n in

   (real r):   print(("real:", r)),

   (int i):    print(("int:", i)),

   (compl c):  print(("compl:", c)),

   (string s): print(("string:", s))

   out         print(("?:", n))

 esac

1970s & 1980s

Although primarily only functional languages such as ML and Haskell (from 1990s) give a central role to tagged unions and have the power to check that all cases are handled, other languages have support for tagged unions as well. However, in practice they can be less efficient in non-functional languages due to optimizations enabled by functional language compilers that can eliminate explicit tag checks and avoid explicit storage of tags.

Pascal, Ada, and Modula-2 call them variant records, and require the tag field to be manually created and the tag values specified, as in this Pascal example:

type shapeKind = (square, rectangle, circle);

     shape = record

                centerx : integer;

                centery : integer;

                case kind : shapeKind of

                   square : (side : integer);

                   rectangle : (length, height : integer);

                   circle : (radius : integer);

              end;

In C and C++, a tagged union can be created from untagged unions using a strict access discipline where the tag is always checked:

enum ShapeKind { Square, Rectangle, Circle };

struct Shape {

    int centerx;

    int centery;

    enum ShapeKind kind;

    union {

        struct { int side; }           squareData;

        struct { int length, height; } rectangleData;

        struct { int radius; }         circleData;

    } shapeKindData;

};

int getSquareSide(struct Shape* s) {

    assert(s->kind == Square);

    return s->shapeKindData.squareData.side;

void setSquareSide(struct Shape* s, int side) {

    s->kind = Square;

    s->shapeKindData.squareData.side = side;

/* and so on */

As long as the union fields are only accessed through the functions, the accesses will be safe and correct. The same approach can be used for encoded tags; we simply decode the tag and then check it on each access. If the inefficiency of these tag checks is a concern, they may be automatically removed in the final version.

C and C++ also have language support for one particular tagged union: the possibly-null pointer. This may be compared to the option type in ML or the Maybe type in Haskell, and can be seen as a tagged union (with an encoded tag) of two types:

Valid pointers,
A type with only one value, null, indicating an exceptional condition.

Unfortunately, C compilers do not verify that the null case is always handled, and this is a particularly prevalent source of errors in C code, since there is a tendency to ignore exceptional cases.

2000s

One advanced dialect of C called Cyclone has extensive built-in support for tagged unions. See the tagged union section of the on-line manual for more information.

Gap buffer

A gap buffer is a data structure used to store long arrays compactly, while still allowing efficient insertion and deletion operations, provided that the operations are clustered near the same location. Gap buffers are especially common in text editors, where most changes to the text occur at or near the current location of the cursor. The text is stored in a large buffer in two contiguous segments, with a gap between them for inserting new text. Moving the cursor involves copying text from one side of the gap to the other (sometimes copying is delayed until the next operation that changes the text). Insertion adds new text at the end of the first segment. Deletion increases the size of the gap.

The advantage of using a gap buffer over more sophisticated data structures (such as linked lists) is that the text is represented simply as two literal strings, which take very little extra space and which can be searched and displayed very quickly.

The disadvantage is that operations at different locations in the text and ones that fill the gap (requiring a new gap to be created) require re-copying most of the text, which is especially inefficient for large files. The use of gap buffers is based on the assumption that such recopying occurs rarely enough that its cost can be amortized over the more common cheap operations.

A gap buffer is used in most Emacs editors.

Example

Below are some examples of operations with buffer gaps. The gap is represented pictorially by the empty space between the square brackets. This representation is a bit misleading: in a typical implementation, the endpoints of the gap are tracked using pointers, and the contents of the gap are ignored; this allows, for example, deletions to be done by adjusting a pointer without changing the text in the buffer.

Initial state:

This is the way [                    ]out.

User inserts some new text:

This is the way the world started [   ]out.

User moves the cursor before "started"; system moves "started " from the first buffer to the second buffer.

This is the way the world [   ]started out.

User adds text filling the gap; system creates new gap:

This is the way the world as we know it [                   ]started out.

Memory - part 7

Dual-channel DDR

The terminology "dual-channel DDR" is, in fact, a misnomer. The fact is there's no such thing as dual-channel DDR memory. What there are, however, are dual-channel platforms.

When properly used, the term "dual channel" refers to a DDR motherboards chipset that's designed with two memory channels instead of one. The two channels handle memory-processing more efficiently by utilising the theoretical bandwidth of the two modules, thus reducing system latencies, the timing delays that inherently occur with one memory module. For example, one controller reads and writes data while the second controller prepares for the next access, hence, eliminating the reset and setup delays that occur before one memory module can begin the read/write process all over again.

Consider an analogy in which data is filled into a funnel (memory), which then "channels" the data to the CPU.

Single-channel memory would feed the data to the processor via a single funnel at a maximum rate of 64 bits at a time. Dual-channel memory, on the other hand, utilises two funnels, thereby having the capability to deliver data twice as fast, at up to 128 bits at a time. The process works the same way when data is "emptied" from the processor by reversing the flow of data. A "memory controller" chip is responsible for handling all data transfers involving the memory modules and the processor. This controls the flow of data through the funnels, preventing them from being over-filled with data.

It is estimated that a dual-channel memory architecture is capable of increasing bandwidth by as much as 10%.

The majority of systems supporting dual-channel memory can be configured in either single-channel or dual-channel memory mode. The fact that a motherboard supports dual-channel DDR memory, does not guarantee that installed DIMMs will be utilised in dual-channel mode. It is not sufficient to just plug multiple memory modules into their sockets to get dual-channel memory operation - users need to follow specific rules when adding memory modules to ensure that they get dual-channel memory performance. Intel specifies that motherboards should default to single-channel mode in the event of any of these being violated:

DIMMs must be installed in pairs
Both DIMMs must use the same density memory chips
Both DIMMs must use the same DRAM bus width
Both DIMMs must be either single-sided or dual-sided.

DDR SDRAM DIMMs have 184 pins (as opposed to 168 pins on SDRAM, or, 240 pins on DDR2 SDRAM), and can be differentiated from SDRAM DIMMs by the number of notches (DDR SDRAM has one, SDRAM has two).

1T-SRAM

Historically, while much more cost effective than SRAM per Megabit, traditional DRAM has always suffered speed and latency penalties making it unsuitable for some applications. Consequently, product manufacturers have often been forced to opt for the more expensive, but faster SRAM technology. By 2000, however, system designers had another option available to them, and one that offers the best of both worlds: fast speed, low cost, high density and lower power consumption.

Though the inventor of 1T-SRAM - Monolithic System Technology Inc. (MoSys) - calls its design an SRAM, it is in fact based on single-transistor DRAM cells. As with any other DRAM, the data in these cells must be periodically refreshed to prevent data loss. What makes the 1T-SRAM unique is that it offers a true SRAM-style interface that hides all refresh operations from the memory controller.

Traditionally, SRAMs have been built using a bulky four or six transistor (4T, 6T) cell. The MoSys 1T-SRAM device is built on a single transistor (1T) DRAM cell, allowing a reduction in die size by between 50% and 80% compared to SRAMs of similar density. Moreover, its high density is achieved whilst at the same time maintaining the refresh-free interface and low latency random memory access cycle time associated with traditional six-transistor SRAM cells. As if these exceptional density and performance characters weren't enough, 1T-SRAM technology also offers dramatic power consumption savings by using under a quarter of the power of traditional SRAM memories!

1T-SRAM is an innovation that promises to dramatically change the balance between the two traditional memory technologies. At the very least it will provide DRAM makers with the opportunity to squeeze significantly more margin from their established DRAM processes.

Networking: four steps of your networking plan

network which is simply a group of people in which you can share your ideas, information, your resources plus you can introduce your network members with each other to help each of your network members towards a common goal.

In the book, Think and Grow Rich, Napoleon Hill talks about building your network into your Mastermind Group which is simply a refined network that will help you in your path towards obscene wealth and success. There are many examples of people in the book Think and Grow Rich that built their own networks to help them achieve the success they are looking for.

In the chapter, Desire, Napoleon Hill talked about how Edwin C Barnes had the Desire to become a business partner of Thomas A Edison. He achieved his objective by building a network that helped him get to the point where he was an equal and become the partner of Thomas Edison.

Knowing where and how to start building your network is the toughest challenge. Below I have set out four basic steps as part of your Networking Plan.

Step 1. Define Your Desire

Napoleon Hill teaches us in Think and Grow Rich that you can only achieve what you truly Desire and this is also true of networking. What is your desire of building your network and the people in your network?

For example your Desire of your network might be to build a network of like minded businesses, for instance you might be a builder and your network you want to build might include painters, decorators, architects, Loan specialists etc. The Desire of your network maybe to bring 60% of your business from your network.

Essentially what you must do when starting to build your network is to identify what you Desire your network to be. Make sure that you write out your Desire at the top of the page so that you can easily visualize what your Desire is.

Step 2. Set Out Your Goals

Once you have a clear Desire, your next step is to define the goals of that desire. Earlier I gave you the example of a network that you might desire as a builder. The desire of the builders' network was to have painters, decorators, architects, loan specialists in the network. In the goals section of this four step process you must identify specific targets.

In Napoleon Hills chapter, Autosuggestion he states that for you to achieve your Desire it must be something that you can see as tangible. Simply having the desire to be Rich will never allow you to achieve anything, but having the desire to make $400,000 Cash is a tangible desire and goal you can achieve. The same is true of networking.

If you are building your network, you need to state in your goals specifically which painters, decorators and architects you want to be apart of your network. You should write those tangible goals down because these are the people you want to build your plan around to achieve your network.

Step 3. Develop Your Plan

The third step in your Networking Plan is to work out how you are going to network with these Target people. Your plan must involve a lot of research to identify where they spend their time and how you are going to meet them in a networking environment.

For example, your target architect maybe a member of Rotary so your plan that you are developing maybe to find a way through your current network to join the same Rotary Group that your target architect is a member of. In your plan you may identify that you will go to four meetings and introduce yourself four times before asking to have coffee with this person or to meet at some other function to get to know them more intimately.

Before you set those meetings into stone you need to do some research on their business but also the right questions to ask them. Remember the key to being a Master Networker is to make the target feel important and ask them about their business. It should not be your agenda to push your business down their throat. You will find that after a period they will naturally ask you about yours and when that situation arises it is your turn to introduce your business.

One of the other tasks that I recommend that you as part of this step is to practice the delivery of your questions. I also recommend that you commit your questions to memory before meeting with these Target people. The reason you should do this practice is to ensure that your delivery of the questions is natural rather than being staged. I strongly encourage you to ask a colleague to help you master these questions and to practice how you deliver them during a networking function.

Step 4. Implement Your Plan

Once you have developed your plan, the final phase is to implement your plan and to get out and start meeting the people you want to make apart of your network.

The bottom line is this, networking is a skill and like any skill it will take time to practice and that is why you must follow the four step process. Remember, elite swimmers do not win Olympic gold without a clear plan and a lot of practice and networking is no different. To finish off I want to simply outline the four steps in your networking plan.

Step 1. Define Your Desire
Step 2. Set Out Your Goals
Step 3. Develop Your Plan
Step 4. Implement Your Plan

Motherboards - part 5

NLX

Intel's NLX design, introduced in 1997, is an improvement on the LPX design for low-profile systems, with an emphasis on ease of maintenance. The NLX format is smaller, typically 8.8in wide by 13in long, so well suited for low-profile desktop cases.

All expansion slots, power cables and peripheral connectors are located on an edge-mounted riser card, allowing simple removal of the main motherboard, which is mounted on rails in the chassis. It uses a full-width I/O shield to allow for different combinations of rear-panel I/O. The design allows for use of an AGP card, but the slot must be on the motherboard, which reduces the ease of maintenance when such a card is implemented.

MicroATX

Introduced in the late 1990s, the MicroATX is basically a smaller version of Intel's ATX specification, intended for compact, low-cost consumer systems with limited expansion potential.

The maximum size of the board is 9.6in square, and its designed to fit into either a standard ATX case or one of the new micro-tower desktop designs. The double-decker I/O shield is the same as that on the ATX design, but there's only provision for up to four expansion slots as opposed to the seven that ATX allows. The microATX also allows use of a smaller power supply, such as the SFX design, which is reduced in both size and power output.

FlexATX

The FlexATX is a natural evolution of the Intel's microATX form factor which was first unveiled in late 1999. The FlexATX addendum to the microATX specification addresses the requirements of only the motherboard and not the overall system solution. As such, it does not detail the interfaces, memory or graphics technologies required to develop a successful product design. These are left to the implementer and system designer. The choice of processor is, however, limited to socket-only designs.

The principal difference between FlexATX and microATX is that the new form factor reduces the size of the motherboard - to 9in x 7.5in. Not only does this result in lower overall system costs, it also facilitates smaller system designs. The FlexATX form factor is backwards compatible with both the ATX and micro-ATX specifications - use of the same motherboard mounting holes as both of its predecessors avoids the need to retool existing chassis.

In the spring of 2000 VIA Technologies announced an even smaller motherboard than the FlexATX. At 8.5in x 7.5in, the company's ITX form factor is half and inch less wide than its Intel competitor. The key innovation that allows the ITX to achieve such a compact form is the specially designed slimline power unit with built in fan. Its dimensions of 174mm long x 73mm wide x 55mm high compare with a standard ATX power supply unit measuring 140mm x 150mm x 86mm.

Unsurprisingly Intel's FlexATX form factor uses it's CNR riser architecture, while the ITX uses the rival ACR architecture.

BTX

Intel has been promoting its Balanced Technology Extended specification for a while before the company began, in late 2004, to push in earnest to establish the BTX form factor as the replacement for the aging ATX motherboard and chassis specification.

The BTX form factor is a scalable form factor that allows for a wide range of system sizes and profiles. There are several benefits associated with a properly designed BTX system over designs from previous form factor specification generations. These benefits include scalability in system design, improvements to system power delivery and power dissipation, acoustics, board layout and routing, high volume manufacturing costs, and structural integrity.

A BTX motherboard positions its internal components in such a way as to as to allow the CPU heat sink and other hot-running chips to be cooled by a single airflow stream. The idea is that, in addition to the power supply's internal fan, it should be possible to cool an entire system with just a single chassis fan. BTX refers to this new heat-sink-and-fan combination as a "Thermal Module". A typical thermal module includes a heatsink for the processor, an air mover such as an axial fan and a duct to isolate and direct airflow through the system.

Since the required direction of airflow is from front to back, the design required that particular attention be paid to acoustic management strategies so as to compensate for the fan now being a noise source that is generally directly in front of the system user.

The BTX specification is designed to encompass a family of board sizes for a range of system sizes. It's like having ATX, microATX, and FlexATX form factors all being covered by a single specification. A standard BTX design measures 325mm x 266mm and supports up to seven add-in card slots. For sizing down to smaller form factors, Intel is providing two different designs: a microBTX, measuring 264mm x 266mm with up to 4 add-in card slots and a picoBTX measuring 203mm x 266mm with up to 1 add-in card slot.

In fact, the BTX specification offers even greater flexibility than ATX family of form factors, supporting not only different board sizes, but also different system heights. The standard height is similar to the height defined in the ATX-family form factor. An additional, lower profile height is defined for use where it is important to reduce the overall size of the system.

Kaspersky Anti Virus Antivirus 7 Review

Kaspersky Anti-Virus 7
Last year's CNET Editors' Choice award winner Kaspersky returns with another winner. Kaspersky Anti-Virus 7 features a new interface and new protection. But, unlike last year, the competition for Editors' Choice in this space was fierce with several worthy contenders all bunching toward the top of the scale. For example, BitDefender Antivirus 2008 is perhaps the most improved product of the year, nipping at the heals of Kaspersky. What makes Kaspersky Anti-Virus continue to outshine its competition is its ease of use combined with thorough antivirus protection. No firewall, no gimmicks, just straight AV protection. Kaspersky also makes an Internet security suite, yet Kaspersky Anti-Virus 7 feels complete as a standalone product and not, like Norton Antivirus 2008, a cog in larger family of products. That said, there is no firewall protection within Kaspersky Anti-Virus 2008, leaving you to choose your own firewall protection. Once again, Kaspersky requires considerably less disk space than Norton. The only real negative here is the list price, which can be $10 to $20 more than the competition, depending where you purchase it. Still, Kaspersky Anti-Virus 7 provides the most complete antivirus production on the market today and deserves our Editors' Choice for best antivirus product for 2008.

We experienced no problems with several different installations during the month of August. After installation, the system requires a reboot for full protection.

Should you want to remove Kaspersky Anti-Virus 7, the product includes an uninstall option in the All Programs menu. Once we uninstalled the product and rebooted, we found no lingering evidence of Kaspersky remaining on our machine.

Interface
Kaspersky Anti-Virus 7 sports a cleaner, more sophisticated interface than last year's. We like it best among the 2008 antivirus applications we've seen. Immediately our eye was drawn to the red banner with text that told us our signature files were out of date. This is visually very effective and efficient, whereas a simple Fix It button to the side is not always informative. Also, unlike Norton's morbid, black border, we like the open, bright, and colorful interface of Kaspersky that is skinnable to suite your own tastes.

We like Kaspersky Anti-Virus 7's clean, intuitive interface best among the 2008 antivirus applications we've seen.

Another interface feature we like is the left navigation. Within seconds, we were able to find the configuration settings we wanted to tweak.

In addition to antivirus and antispyware protection, Kaspersky offers antirootkit protection as well. We like the built-in System Restore, so that should your computer ever become infected, Kaspersky will roll back any registry changes to a time prior to the infection. This is effective against spyware and rootkits.

Features
Not only is the malware protection within Kaspersky proactive, with top-of-the-line heuristics to identify newly created malware, and, like BitDefender Antivirus 2008, Kaspersky's traditional signature-based protection is updated hourly, along with any available program updates. We like this approach, as Kaspersky seems to have figured out what Norton has not: how to deliver small file updates. Plus, Kaspersky has consistently demonstrated the shortest response time to breaking new malware threats.

Kaspersky still provides users with the process of creating a rescue disk, something that many antivirus products no longer offer. And, Kaspersky Anti-Virus 7 includes a process so that the operating system can revert back to a time just before an infection. Like Norton, Kaspersky can also throttle back on system resources, depending on user activity. Unlike Norton, Kaspersky can, by default, scan only recently changed files, greatly shortening the overall scan time considerably.

Performance
Kaspersky Anti-Virus 7 scored well in CNET Labs' performance tests and in third-party, independent antivirus testing using live viruses, although not always the top position. On the CNET iTunes test, Kaspersky Anti-Virus 7 came in just 4 seconds above the test system at 272 seconds. On the CNET Microsoft Office test, Kaspersky Anti-Virus 7 finished in 1,518 seconds. In a test scanning a single folder with compressed and media files, Kaspersky Anti-Virus 7 completed it in 521 seconds. And in boot speed, Kaspersky came in second, with a fast 29.77 seconds. To find out how we test antivirus software , see CNET Labs' How we test: Antivirus software page.

In terms of whether or not Kaspersky Anti-Virus 7 will protect your PC, we cite results from two leading independent antivirus testing organizations. In the latest test results from AV-Comparatives.org, for on-demand scans Kaspersky Anti-Virus 7 earned an Advanced + (highest) rating, catching 98 percent of all malware tested and tying with Norton Antivirus 2007. However, for the Retrospective/Proactive test, Kaspersky Anti-Virus 7 earned an Advanced (second-highest) rating, although Kaspersky produced very few false positives compared with other antivirus apps in the same test. From CheckVir.com, there is no data. Kaspersky Anti-Virus 7 was not included in recent tests, however, when it was last tested, Kaspersky Anti-Virus 6 earned a Standard rating when only the ability to search is tested, not antivirus removal.

Support
Kaspersky Anti-Virus 7 provides an excellent context-sensitive, in-program help file. For example, if you are on the Data Files page and you click Help, you're taken to the entry for Data Files within the Help file. It's a small touch, but one we don't see often enough. Kaspersky offers a robust 321-page PDF manual (the most complete of any antivirus application we've seen); it includes just about everything--except for an index, although the table of contents is richly detailed. Kaspersky also delivers excellent online FAQ and knowledge base. There are also active user forums. Finally, you can e-mail or call a toll-free number for live technical support.

Conclusion
If you're looking for an antivirus application that's good, fast, and light on system resources, Kaspersky is the one. We found this antivirus application easy enough for beginners, with customization features that will please more-advanced users, as well. But, with the competition gaining, by no means was this a knockout; this year's Editors' Choice race was tighter than ever.

The good: Kaspersky Anti-Virus 7 sports an intuitive, fresh interface that is skinnable, offers excellent technical support, and easily vanquishes viruses, spyware, rootkits, phishing, and other malware.

The bad: Kaspersky Anti-Virus 7 can be slightly more expensive than the competition, and firewall protection is missing.

The bottom line: Kaspersky Anti-Virus 7 continues to outshine its competition with its ease of use combined with thorough antivirus protection.

System Requirements
Min Processor Type Intel Pentium 300 MHz or higher (Microsoft Windows 2000 Professional SP 4 and higher), Intel Pentium 300 MHz or higher (Microsoft Windows XP Home Edition SP 2 and higher), Intel Pentium 300 MHz or higher (Microsoft Windows XP Professional SP 2 and higher) Peripheral / Interface Devices CD-ROM System Requirements Details Microsoft Windows 2000 Professional SP 4 and higher - HD 50 MB, Microsoft Windows XP Home Edition SP 2 and higher, Microsoft Windows XP Professional SP 2 and higher, Microsoft Windows XP Professional x64 Edition, Microsoft Windows Vista Home Basic, Microsoft Windows Vista Business, Microsoft Windows Vista Enterprise, Microsoft Windows Vista Ultimate

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Power Supply Tips

The power supply keeps things in your computer running smoothly. When they run well, you won't even think about them, but when things go wrong, it can become very annoying.

The power supply doesn't just run the power to the different parts of the computer. It needs to run different voltages to different parts, and besides that, it has to deliver them within a very tight range set out in the ATX standard.

Power supplies went through a phase of being extremely unreliable. This is because the actual parts are very cheap and standard and the profit margin in the power supply business is higher than almost any other computer part. The flooding of the market with poor quality power supplies led to lots of failures and complaints.

More recently, the problems in that sector have decreased, the general quality and build of power supplies has increased to a level where nearly any power supply will deliver what it claims it will and within specs. Most, but not all.

As with computer monitors, power supplies are one part that does not need to be upgraded very often. The only additions have come from SATA specific power plugs and the additional P4 plug in recent years and even those are not always necessary.

So what do you actually need from a power supply?

The most basic requirement is that its power output can match the power needed by the components inside your computer. Each part has its own requirement and its own maximums and minimums on what it needs. The claimed maximum power for each voltage are added together to give the power rating for the power supply.

The main power user in the computer is the CPU. Some Pentium 4 processors are known to gobble lots of power. Hard drives use some power too, but no more than 10W each, optical drives even less. The motherboard itself uses some too. The other major user of power are graphics cards.

As graphics cards have become more powerful, and with the advent of Graphical Processing Units (GPUs), which are like CPUs which are dedicated to graphics work, and situated on the graphics card, they can now use more power than a CPU. If you are running a very fast PCIe graphics card or a pair of them, you will need more power.

At the most basic a 300W power supply will be more than enough for most day to day use desktop computers, even if they have a small AGP graphics card. Only get more than 300W if you know you need it, or expect you will need it in the future after upgrades. 500W will more than suffice for even the most demanding system with 2 graphics cards, but it needs to be a reputable brand.

Enermax, Antec, Fortron and Seasonic are good names in the power supply business, you will not go wrong with their products. Even though there is a small price premium, the security in knowing that nothing will go wrong is worth it. Another power supply I like is the X-connect from Ultra. Each of the cables that come from the power supply are removable, so only the ones you are using need to be in the box. Very convenient and neat, as long as I don't lose the cables.

Pre-assembled computers are known for having the cheapest power supplies in them. As no-one really checks the power supply when buying they just put the minimum inside. These are usually fine, but will often buckle under the load of extra upgrades you may make. Bear in mind that you might have to upgrade the power supply when installing those new, really cool graphics cards.

So, keep these things in mind...
- Stick to major brands
- 300W only unless particularly needed
- Functionality before looks

Pda and pocket pc technologies

Wireless devices are not always cellular phones. In fact, they do not even need voice capabilities. Does you home PC have a telephone receiver hanging on it? Of course not: The computer s primary function is to do meaningful data crunching!

Personal digital assistants and pocket PCs were created to provide a certain level of support for the mobile user, which could only previously be available on a laptop PC, but smaller and lighter. They are not primarily voice communications devices they are for storage, retrieval, and manipulation of data. Some PDAs and pocket PCs may attach to a cellular phone or other type of wireless modem, but only for the wireless connectivity of data communications. At least one manufacturer s cellular phone has a PDA built-in. It is immaterial whether we choose to call it a phone with PDA or a PDA with a phone built into it.

There is an entire class of devices devoted to wireless mobile data. Some PDAs are primarily email devices. Others are more generic and can run many different applications, such as the Palm Pilot or Visor. All, however, fall into two categories: They either use public cellular for communications or they use other public or private networks. They all share the same limitations for data transmission, and they are limited to the current state of the art of the physical access channel. Except for Ricochet, this means 19.2 Kbps or less. When they are upgraded to next-generation cellular, data rates will increase.

One very interesting thing to watch will be the migration or upgrade paths for the noncellular networks when competition for higher data rates begins. Most are using 19.2 Kbps for wireless PDA and Pocket PC communications.

RIM AND BLACKBERRY

Research in Motion makes RIM and Blackberry wireless handheld models for a variety of applications and personal preferences, including an OEM version. Some models are primarily for Internet email, whereas other models include the functionality to run application software such as calendars, address books, and much more. The devices fit in the palm of a user s hand and are lightweight. Wireless communications is through one of two different networks, Mobitex or DataTAC (Ardis Network).

Both Mobitex and DataTAC are packet-switched, narrowband PCS networks designed for wide-area wireless data communication at a data rate of 19.2 Kbps. They provide always-on connections with extensive coverage and in-building penetration, seamless roaming, fast messaging, high reliability, and advanced messaging services. Dialing up to retrieve emails is unnecessary.

PALM

Palm offers several Wireless Internet options. Their integrated wireless solution is the Palm VIIx with service provided by Mobitex. Other Palm products can add a modem or connect to a cellular phone. One wireless service used by Palm is OmniSky, which offers CDPD at 19.2 Kbps. This, of course, operates over an analog cellular network. Because analog cellular coverage is very ubiquitous in North America, this provides broad user coverage when traveling. It also carries all of the advantages of CDPD, like packet data transmission and always-on mode.

Downloading Web pages with Palm products involves a little trick called Web clipping. The user requests a particular piece of information in a query, and the page is returned minus a lot of the extraneous details. A server gateway is used to optimize the content for displaying on the handheld PDA.

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ZoneAlarm Zone Alarm AntiVirus 2007 Anti Virus 7.1 Review

Along with its effective and easy-to-use firewall protection, ZoneAlarm with Antivirus adds virus features and security controls. The most notable improvements in this latest release are enhanced virus detection and an Auto-Learn function to minimize unnecessary security alerts.

ZoneAlarm's wizard makes firewall configuration and maintanence incredibly easy, with a stylish interface and simple slider controls. The app boasts an ultrasecure triple-layer firewall and experts will appreciate the customizing options. The Zones feature allows you to assign different security levels for local networks and the Internet. The program was very good at automatically including our local network settings and auto-detected wireless machines. In all our tests, the firewall held strong against all threats it encountered.

Beyond the firewall function, ZoneAlarm with Antivirus includes an antivirus scanner, based on Computer Associates' Vet Anti-Virus, that blocks both incoming and outgoing viruses. The most intriguing aspect of this feature is its Advanced Heuristic Detection algorithm, which uses behavior analysis to detect suspicious actions caused by brand-new viruses that haven't yet made it into the virus-definitions database. Though this version of ZoneAlarm lacks the privacy and identity features of the Pro version, users who are satisfied with their existing privacy-protection tools may find ZoneAlarm with Antivirus fits their needs.

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Interfaces - part 12

IEEE 1394

Also widely referred to as FireWire, IEEE 1394 was approved by the Institute of Electrical and Electronics Engineers (IEEE) in 1995. Originally conceived by Apple, who currently receives $1 royalty per port, several leading IT companies - including Microsoft, Philips, National Semiconductor and Texas Instruments - have since joined the 1394 Trade Association.

IEEE 1394 is similar to the first version of USB in many ways, but much faster. Both are hot-swappable serial interfaces, but IEEE 1394 provides high-bandwidth, high-speed data transfers significantly in excess of what USB offers. There are two levels of interface in IEEE 1394, one for the backplane bus within the computer and another for the point-to-point interface between device and computer on the serial cable. A simple bridge connects the two environments. The backplane bus supports data-transfer speeds of 12.5, 25, or 50 Mbit/s, the cable interface speeds of 100, 200 and 400 Mbit/s - roughly four times as fast as a 100BaseT Ethernet connection and far faster than USB's 1.5 Mbit/s or 12 Mbit/s speeds. A 1394b specification aims to adopt a different coding and data-transfer scheme that will scale to 800 Mbit/s, 1.6 Gbit/s and beyond. Its high-speed capability makes IEEE 1394 viable for connecting digital cameras, camcorders, printers, TVs, network cards and mass storage devices to a PC.

IEEE 1394 cable connectors are constructed with the electrical contacts inside the structure of the connector thus preventing any shock to the user or contamination to the contacts by the user's hands. These connectors are derived from the Nintendo GameBoy connector. Field tested by children of all ages, this small and flexible connector is very durable. These connectors are easy to use even when the user must blindly insert them into the back of machines. There are no terminators required, or manual IDs to be set.

IEEE 1394 uses a six-conductor cable (up to 4.5 metres long) which contains two pairs of wires for data transport, and one pair for device power. The design resembles a standard 10BaseT Ethernet cable. Each signal pair is shielded and the entire cable is shielded. Cable power is specified to be from 8Vdc to 40Vdc at up to 1.5 amps and is used to maintain a device's physical layer continuity when the device is powered down or malfunctioned - a unique and very important feature for a serial topology - and provide power for devices connected to the bus. As the standard evolves, new cable designs are expected to allow longer distances without repeaters and with more bandwidth.

At the heart of any IEEE 1394 connection is a physical layer and a link layer semiconductor chip, and IEEE 1394 needs two chips per device. The physical interface (PHY) is a mixed signal device that connects to the other device's PHY. It includes the logic needed to perform arbitration and bus initialisation functions. The Link interface connects the PHY and the device internals. It transmits and receives 1394-formatted data packets and supports asynchronous or isochronous data transfers. Providing both asynchronous and isochronous formats on the same interface allows both non-real-time critical applications, such as printers and scanners, and real-time critical applications, such as video and audio, to operate on the same bus. All PHY chips use the same technology, whereas the Link is device-specific. This approach allows IEEE 1394 to act as a peer-to-peer system as opposed to USB's client-server design. As a consequence, an IEEE 1394 system needs neither a serving host, nor a PC.

Asynchronous transport is the traditional method of transmitting data between computers and peripherals, data being sent in one direction followed by acknowledgement to the requester. Asynchronous data transfers place emphasis on delivery rather than timing. The data transmission is guaranteed, and retries are supported. Isochronous data transfer ensures that data flows at a pre-set rate so that an application can handle it in a timed way. This is especially important for time-critical multimedia data where just-in-time delivery eliminates the need for costly buffering. Isochronous data transfers operate in a broadcast manner, where one or many 1394 devices can "listen" to the data being transmitted. Multiple channels (up to 63) of isochronous data can be transferred simultaneously on the 1394 bus. Since isochronous transfers can only take up a maximum of 80 percent of the 1394 bus bandwidth, there is enough bandwidth left over for additional asynchronous transfers.

IEEE 1394's scaleable architecture and flexible peer-to-peer topology make it ideal for connecting high-speed devices: everything from computers and hard drives, to digital audio and video hardware. Devices can be connected to in either a daisy-chain or tree topology. The diagram depicts two separate work areas connected with a 1394 bridge. Work area #1 comprises a video camera, PC, and video recorder, all interconnected via IEEE 1394. The PC is also connected to a physically distant printer via a 1394 repeater, which extends the inter-device distance by redriving the 1394 signals. Up to sixteen hops may be made between any two devices on a 1394 bus. A 1394 splitter is used between the bridge and the printer to provide another port to attach a 1394 bus bridge. Splitters provide more topology flexibility for users.

Work area #2 contains only a PC and printer on a 1394 bus segment, plus a connection to the bus bridge. The 1394 bus bridge isolates data traffic within each work area. IEEE 1394 bus bridges allow selected data to be passed from one bus segment to another. Therefore PC #2 can request image data from the video recorder in work area #1. Since the 1394 cable is powered, the PHY signalling interface is always powered, and video data is transported even if PC #1 is powered off.

Each IEEE 1394 bus segment may have up to 63 devices attached to it. Currently each device may be up to 4.5 metres apart; longer distances are possible with and without repeater hardware. Improvements to the current cabling are being specified to allow longer distance cables. Over 1000 bus segments may be connected by bridges thus providing a large growth potential. An additional feature is the ability of transactions at different speeds to occur on a single device medium. For example, some devices can communicate at 100 Mbit/s while others communicate at 200 Mbit/s and 400 Mbit/s. IEEE 1394 devices may be hot-plugged - added to or removed from the bus - even with the bus in full operation. Upon altering the bus configuration, topology changes are automatically recognised. This "plug and play" feature eliminates the need for address switches or other user intervention to reconfigure the bus.

As a transaction-based packet technology, 1394 can be organised as if it were memory space interconnected between devices, or as if devices resided in slots on the main backplane. Device addressing is 64 bits wide, partitioned as 10 bits for network Ids, 6 bits for node Ids and 48 bits for memory addresses. The result is the capability to address 1023 networks of 63 nodes, each with 281TB of memory. Memory-based addressing, rather than channel addressing, views resources as registers or memory that can be accessed with processor-to-memory transactions. Fundamentally, all this means easy networking - for example, a digital camera can easily send pictures directly to a digital printer without a computer in the middle - and with IEEE 1394 it is easy to see how the PC could lose its position of dominance in the interconnectivity environment and be relegated to being no more than a very intelligent peer.

The need for two pieces of silicon instead of one will make IEEE 1394 peripherals more expensive than, say, SCSI, IDE or USB devices. Consequently it is inappropriate for low speed peripherals. However, its applicability to higher-end applications, such as digital video editing, is obvious and its clear that the standard is destined to become a mainstream consumer electronics interface - used for connecting handy-cams and VCRs, set-top boxes and televisions. To date, however, its implementation has been largely confined to digital camcorders, where is it known as iLink.

In 1997, Compaq, Intel and Microsoft proposed an industry standard called Device Bay. By combining the fast interface of IEEE 1394 with the USB interface, Device Bay offered a bay slot to slide in peripherals such as hard disks or DVD-ROM players. The following year, however, proved to be a somewhat troubled year for IEEE 1394, with Apple's announcement of what many believed to be exorbitant royalty claims for use of the technology deterring many semiconductor companies who had hitherto embraced the standard. Notwithstanding these issues - and largely because of its support of isochronous data transfer - by the start of the new millennium FireWire had established itself as the favoured technology in the area of video capture.

Indeed, its use as a hard disk interface offers a number of advantages over SCSI. Whilst its maximum data transfer speed of 400 Mbit/s (equivalent to 50 MBps) isn't as fast as the Ultra160 SCSI standard, FireWire beats SCSI hands down when it comes to ease of installation. Where SCSI devices require a pre-assigned ID and both ends of the bus to be terminated, IEEE 1394 will dynamically assign addresses on the fly and does not require terminators. Like USB, FireWire devices are also hot-swappable, without the need to power down the PC during installation. Combined with its lack of previous stumbling blocks such as the assignment of IRQs or DMAs - these characteristics make IEEE 1394 perfect for trouble-free plug and play installations.

Despite all this, and the prospect of a number of motherboard manufacturers producing boards with built-in IEEE 1394 controllers in the second half of 2000, FireWire's future success was far from assured - the announcement of the proposed USB 2.0 specification at the Intel Developer Forum (IDF) of February 1999 serving to significantly complicate the picture.

How to Install a Front Loading Drive - part 5

Configuring your BIOS

To have the BIOS automatically detect the new drive and set its parameters you need to enter the Standard CMOS Setup category of the BIOS Setup and ensure that the IDE Master and Slave designations are correct for your current configuration.

If a Master or Slave device is set to Disable or None or a similar designation, change it as appropriate to Enable or Auto (or something similar, depending on your setup program).

Save the settings and exit the setup routine, allowing the system to boot from the startup disk.

Installing the software

The computer s operating system, whether it is Windows XP, Windows Me, Windows 98, Windows 95, Windows 2000 or Windows XP supplies a generic CD-ROM device driver that will allow your CD-ReWriter to function as a standard CD-ROM drive. You don t need to install anything else.

However, in order to take advantage of the drive's ability to record on CD-R or CD-RW media, you'll need to install packet writing or mastering applications software on your PC. Such applications - such as Roxio s Easy CD Creator - are generally bundled with CD-ReWriter products.

The Roxio suite comprises three main applications:

CD Copier: Lets you copy any CD.
DirectCD Format Utility: Prepares a CD-R or CD-RW disc so you can directly copy files to it in much the same way that you copy files to a floppy disk or removable drive. You can then use Windows Explorer, or any other program that can read from and write to a drive letter, to copy files to a CD. You can also recover files from damaged CDs, and even repair CDs.
Easy CD Creator: Lets you make your own CDs, including music CDs that can be played on your home or car stereo CD player, or data CDs for storing computer data such as the files and folders on your hard disk.

Memory - part 6

DDR SDRAM

Double Data Rate (DDR) SDRAM is the other competing memory technology battling to provide system builders with a high-performance alternative to Direct RDRAM. As in standard SDRAM, DDR SDRAM is tied to the system's FSB, the memory and bus executing instructions at the same time rather than one of them having to wait for the other.

Traditionally, to synchronise logic devices, data transfers would occur on a clock edge. As a clock pulse oscillates between 1 and 0, data would be output on either the rising edge (as the pulse changes from a "0" to a "1") or on the falling edge. DDR DRAM works by allowing the activation of output operations on the chip to occur on both the rising and falling edge of the clock, thereby providing an effective doubling of the clock frequency without increasing the actual frequency.

DDR-DRAM first broke into the mainstream PC arena in late 1999, when it emerged as the memory technology of choice on graphics cards using nVidia's GeForce 256 3D graphics chip. Lack of support from Intel delayed its acceptance as a main memory technology. Indeed, when it did begin to be used as PC main memory, it was no thanks to Intel. This was late in 2000 when AMD rounded off what had been an excellent year for the company by introducing DDR-DRAM to the Socket A motherboard. While Intel appeared happy for the Pentium III to remain stuck in the world of PC133 SDRAM and expensive RDRAM, rival chipset maker VIA wasn't, coming to the rescue with the DDR-DRAM supporting Pro266 chipset.

By early 2001, DDR-DRAM's prospects had taken a major turn for the better, with Intel at last being forced to contradict its long-standing and avowed backing for RDRAM by announcing a chipset - codenamed "Brookdale" - that would be the company's first to support the DDR-DRAM memory technology. The i845 chipset duly arrived in mid-2001, although it was not before the beginning of 2002 that system builders would be allowed to couple it with DDR SDRAM.

DDR memory chips are commonly referred to by their data transfer rate. This value is calculated by doubling the bus speed to reflect the double data rate. For example, a DDR266 chip sends and receives data twice per clock cycle on a 133MHz memory bus. This results in a data transfer rate of 266MT/s (million transfers per second). Typically, 200MT/s (100MHz bus) DDR memory chips are called DDR200, 266MT/s (133MHz bus) chips are called DDR266, 333MT/s (166MHz bus) chips are called DDR333 chips, and 400MT/s (200MHz bus) chips are called DDR400.

DDR memory modules, on the other hand, are named after their peak bandwidth - the maximum amount of data they can deliver per second - rather than their clock rates. This is calculated by multiplying the amount of data a module can send at once (called the data path) by the speed the FSB is able to send it. The data path is measured in bits, and the FSB in MHz.

A PC1600 memory module (simply the DDR version of PC100 SDRAM) uses DDR200 chips and can deliver bandwidth of 1600MBps. PC2100 (the DDR version of PC133 SDRAM) uses DDR266 memory chips, resulting in 2100MBps of bandwidth. PC2700 modules use DDR333 chips to deliver 2700MBps of bandwidth and PC3200 - the fastest widely used form in late 2003 - uses DDR400 chips to deliver 3200MBps of bandwidth.

DDR400 was to prove the limit of DDR technology. In the spring of 2004, the next step in the evolutionary chain emerged, in the shape of the the new DDR2 memory architecture.

DDR2 SDRAM

The transition from DDR to DDR2 memory was more evolutionary than revolutionary, the DDR2 architecture being essentially the same as that of its predecessor, with a number of enhancements designed to provide greater bandwidth and other features that help reduce power consumption:

Higher memory transfer rates: DDR2 supports higher-speed transfer rates than DDR, which is officially found in 266 megatransfers per second (MTps), 333 MTps, and 400 MTps versions. Current DDR2 industry specifications call for 400 MTps, 533 MTps, 667 MTps and 800 MTps.
4n prefetch: DDR2 devices use a 4n prefetch architecture instead of the 2n prefetch used for DDR. Using DDR2, the internal DRAM core is designed to read or write data at four times the width of the device's external interface. In comparison, using DDR the internal DRAM core is designed to read or write data at twice the width of the device's external interface. As a result, the internal DRAM core's 4n prefetch architecture enables DDR2 to attain higher memory transfer rates than DDR.
Reduced voltage: DDR2 devices use a supply voltage of 1.8 volts versus 2.5 volts for DDR - almost a 30 percent decrease in supply voltage. This voltage scaling enhancement has the potential to reduce overall power requirements for the memory subsystem.

DDR2 memories work with higher latencies than DDR memories, meaning that they delay more clock cycles to deliver a requested item of data. For this reason, the performance advantage of DDR2 over DDR was not fully seen in practice until the emergence of DDR2-533 versions, in mid-2004.

DDR2 is not backward compatible with DDR. Although DDR2 modules are the same length as DDR modules, differences exist in connectors, signalling, and supply voltages. For example, on DDR memories the resistive termination necessary for making the memory work is located on the motherboard, while on DDR2 memories this circuit is located inside the memory chip itself. Also, DDR modules have 184 contacts, while DDR2 modules have 240. Thus it is not possible to install DDR2 memories in DDR sockets or vice-versa.

As processor power increased relentlessly - both by means of increased clock rates and wider FSBs - chipset manufacturers were quick to embrace the benefits of a dual-channel memory architecture as a solution to the growing bandwidth imbalance.

How Do Video Cards Work?

Are you wondering, how do video cards work? When a video card is created, manufacturers purposefully don t set it to the maximum speed for a variety of reasons. While most people are satisfied with out-of-the-box performance, serious computer users and gamers seek to run the maximum speeds on their video cards. The process of manipulating that un-accessed speed is called overclocking. However, there is a fine balance between uleashing blazing speed and expecting too much from the overclocked video card.

Hardware Temperature
Because the manufacturers set the video card to a safe level, there is no danger of too much heat being generated that will damage internal hardware. When you overclock a video card, it runs hotter; too much of that heat can increase the internal temperatures inside the computer to dangerous levels.

Find out what your system s maximum internal hardware temperature is from your owner s manual. If you raise the clock speed too dramatically, you can burn out various pieces of hardware. In general, a CPU should not exceed 60 degrees C. There are cooling systems that can be installed in the computer to compensate for the excessive heat output, but depending on the levels, it may not be able to keep up with an overclocked video card.

Instability
When overclocking a video card, there will be a certain point where the system can become unstable. Between the factory default and the maximum ability is a happy medium. Forcing the MHz up in small increments is recommended to test exactly where the sweet spot is. If you reach the point where system instability occurs, back it down to an operable level. As a good rule of thumb, the faster the video card is set, the more often and likely the system is to crash.

How Much Is Too Much?
Overclocking is a way to increase the speed of a video card, and incremental raises can result in a noticeable improvement. However, pushing the limits of speed will almost always result in problems with the computer and cause more headaches in terms of repair or replacement. Do research on your particular card and computer to find the point where speed meets stability to get the most out of your system.

How to Install a Pentium 4 CPU - part 1

This tutorial will take you through the steps involved in installing one of the current 800MHz system bus, dual-channel DDR capable Pentium 4 processors, covering each of the following:

installing the CPU
installing the fan/heatsink assembly
connecting the power supply
installing dual-channel memory.

The tutorial also covers the rather tricky procedure for subsequently removing the special Intel-provided fan/heatsink assembly.

Pentium 4 performance received a significant boost in the spring of 2003, when the fastest system bus speed was increased from 533MHz to 800MHz. By providing support for dual-channel DDR400 memory, the new i875P/i865 chipset platform - announced at the same time - provided the increased memory bandwidth architecture necessary for the faster system bus to be fully exploited, the 6.4GBps of bandwidth this provides being perfectly balanced with the 800MHz FSB.

Confusion can be caused by the use "FSB" and "system bus" terminology. Ever since the introduction of Intel's Dual Independent Bus (DIB) architecture in 1997 it has been common for both terms to be used interchangeably. Sometimes, however, you may see current Pentiums 4s being described as having a 200MHz FSB and - by virtue of the "Quad Pumped" data transfer rates (which mean that data can be sent 4x per clock cycle) - an 800Mz system bus.

Installing the CPU

Your Pentium 4 motherboard should include a manual with installation instructions. Consult both this and any documentation that came with your Pentium 4 processor.
The Pentium 4 uses a FC-PGA2 packaging. While the Integrated Heat Spreader (IHS) affords good protection to the CPU itself, the pins on the underside are fragile and easily bent, so the chip needs to be handled with care.

The CPU chip is designed to fit the Socket 478 form factor. Note that motherboards intended for Pentium 4 CPUs have a special processor retention mechanism, attached via four pushpins surrounding the processor socket.

The release of the first Pentium 4 in late 2000 coincided with the latest on Intel's socket line-up, namely Socket 423. Indicative of the trend for processors to consume ever decreasing amounts of power, the PGA-style Socket 423 had a VRM operational range of between 1.0V and 1.85V. However, Socket 423 had been in use for only a matter of months when Intel muddied the waters still further with the announcement of the new Socket 478 form factor. The principal difference between this and its predecessor was that the newer format socket featured a much more densely packed arrangement of pins known as an FC-PGA2 interface. Also referred to as a micro Pin Grid Array ( PGA), this allows both the size of the CPU itself and the space occupied by the interface socket on the motherboard to be significantly reduced. Socket 478 was introduced to accommodate the 0.13-micron Pentium 4 Northwood core, launched at the beginning of 2002.

Pull the socket handle sideways away from the socket and then raise the lever up to a 90-degree angle.

Carefully align the processor using the gold arrow markings on substrate of the FC-PGA2 package and the socket for reference. This should point towards the lever pivot. The CPU will only fit in the correct orientation.

Taking care not to bend any of the processor pins, carefully insert the processor into the socket. Hold the CPU down firmly with one hand and close and secure the socket lever with the other.

The sticker on the box of the boxed processor (that has the processor speed information, test specification, and lot number) can be removed and placed on the inside of the system chassis that the processor is installed into. This will allow quick access to the information that is no longer available on the top of the processor when the heatsink is installed.

Sony - Vaio PCG-N505X/LT Review

Sony's Vaio launch gave more than a few notebook manufacturers sleepless nights when the first product in the range was launched last year. A new round of product announcements in October included this slim, but highly usable, Vaio PCG-N505X/LT.

Just as before, the accent is on cuteness. Straight out of the box the Vaio draws admiration; it's thinner than a VHS video tape when closed, with the battery pack cleverly doubling as a hinge bar, and it weighs just 1.2kg. The 10.4-inch TFT screen will feel pretty small if you're more familiar with the 14- or even 15-inch screens seen on larger desktop replacement notebooks, but it's quite usable at its top resolution of 1024 x 768. Despite the compact size, the notebook feels strong and reliable; another apparently exceptionally well-made product with the only niggling concern being the usability of the small keyboard.

Powered by a 333MHz Intel Celeron processor, the PCG-N505X/LT has 64MB of memory as standard, along with a 6.4GB hard drive. Sony is keen on digital video, and the Vaio PCG-N505X/LT ships with an i.Link port, otherwise known as FireWire or IEEE1394. On this machine, this is primarily for importing images and video clips from DV cameras (Sony's, of course), and there's a suite of video editing tools installed on the machine as standard.

The new Vaio lacks the usual array of serial, parallel and VGA ports, but these can be added using the supplied slimline 'docking station' that can easily be carried in a briefcase with the Vaio if necessary. Also included in the box with our review machine was a USB-connected floppy drive, plus a CDROM drive that connects via the machine's own PC Card slot.

Sony - Vaio PCG-N505X/LT features - Verdict

This is yet another cute gadget from Sony. By the time you've connected the floppy and CDROM drive, you might as well have bought a full-sized notebook; this is not the most practical of devices. But it is more usable than most of its ilk, and very few people will out-pose you on the train home if you whip out one of these machines.

Sony - Vaio PCG-N505X/LT price

1,449 + VAT

Sony: 0990 424 424

www.vaio.sony-europe.com

How to Install a Pentium 4 CPU - part 2

Installing the fan/heatsink assembly

A boxed Pentium 4 processor includes a high quality unattached fan heatsink specifically designed to provide sufficient cooling to the Pentium 4 processor when used in a suitable chassis environment.
The fan heatsink and clip assembly (A) comprises: B: Clip frame C: Clip levers D: Clip frame corners E: Clip frame latch F: Retention mechanism hook. and attaches to the motherboard-mounted retention mechanism (G).
Normally, there will be thermal interface material attached to the bottom of the processor's fan heatsink. Take care not to damage this. Alternatively, use the enclosed syringe to apply all of the thermal interface material provided to the IHS surface of the processor.
Align the heatsink and clip assembly with the retention mechanism (the fan heatsink is symmetrical) and place it on the processor. Allow the heatsink base to compress (without rotating or twisting) the thermal interface material over the surface of the processor's integrated heat spreader.

With the clip levers in the upward position, push down on all four clip frame corners to secure the clip frame latches to the retention mechanism hooks, making sure the processor fan cable is free from any obstruction and is not trapped under clip frame.
It is important to not allow the heatsink to rotate or twist on the processor's integrated heat spreader. Securing the fan heatsink while closing the clip levers will ensure the thermal interface material is not damaged and the processor will operate correctly.
Close the clips levers in opposing directions, one at a time. The levers require some force to be completely closed.

First, close clip lever 1 while holding the topside of the fan heatsink with your hand.

Then, close clip lever 2 while holding the topside of the fan heatsink with your other hand. Once the clip levers are closed, verify that the heatsink is securely retained and that the clip frame latches are properly engaged with the retention mechanism hooks.

Finally, connect the processor fan cable to the motherboard fan power header. Consult the motherboard manual to determine the correct fan header to use.

When installed, the fan heatsink and clip assembly may cause the motherboard to slightly bend or flex. This is nothing to be concerned about, and provides the proper mechanical support for the processor (with attached fan heatsink and clip assembly) and helps prevent against damage during system shipment.

Computer Monitors

The best course of action to take sometimes isn't clear until you've listed and considered your alternatives. The following paragraphs should help clue you in to what the experts think is significant.

Computer monitors have stayed pretty much the same for a long time. Computers have technically been around since the 1940 s, and the traditional CRT technology has been the standard for computer monitors ever since computers advanced to the point where they could display graphics. Processors have gotten thousands of times faster, hard drives thousands of times bigger, RAM memory thousands of times more efficient, but computer monitors have been basically the same old crap for decades. Don t get me wrong, computer monitors have certainly gotten better, but the basic technology behind them hasn t improved much. That has all changed recently, and computer monitors have finally at least partly caught up to the advances with computers in general.

When looking for a computer monitor today, you have a number of options. The first option is still the traditional CRT, or Cathode Ray Tube, monitor. Even though there are better technologies available now, CRT monitors should not be completely overlooked. As the beginning of 2006, they are still the cheapest computer monitors available, so if you are trying to put together the most economical computer possible, you may want to go with CRT. The CRT technology is also tried and true, and does not suffer from some of the bugs that the newer technologies are sometimes prone to. Also, CRT monitors are supposed to have the fastest response time. The drawbacks are of course their large size, they generally require more power and have a poorer picture quality compared to the newer technologies.

How can you put a limit on learning more? The next section may contain that one little bit of wisdom that changes everything.

LCD displays are making serious inroads into the computer monitor market, and not without good reason. LCD, or Liquid Crystal Display, monitors are much smaller, require less power, and provide a sharper, clearer image compared to CRTs. LCD displays have already become the standard for the laptop computer monitors, and it is only a matter of time before they become the standard for desktops as well. Although they are more expensive than CRTs, the price tags on LCD monitors are rapidly dropping.

Another option you have if you re looking for a computer monitor is the plasma display. Plasma displays are the high-end technology of computer monitors, and carry a heft price tag. They offer a superior picture quality capable of resolutions far greater than CRT or LCD equivalents, and are capable of displaying high definition graphics. Plasma display technology, while improving, still suffers from a number of bugs and an overall short life span, but if you ve got the money to spare, they are certainly worth a look!

Of course, it's impossible to put everything about Computer Monitors into just one article. But you can't deny that you've just added to your understanding about Computer Monitors, and that's time well spent.

Memory - part 4

Fast Page Mode DRAM

All types of memory are addressed as an array of rows and columns, and individual bits are stored in each cell of the array. With standard DRAM or FPM DRAM, which comes with access times of 70ns or 60ns, the memory management unit reads data by first activating the appropriate row of the array, activating the correct column, validating the data and transferring the data back to the system. The column is then deactivated, which introduces an unwanted wait state where the processor has to wait for the memory to finish the transfer. The output data buffer is then turned off, ready for the next memory access.

At best, with this scheme FPM can achieve a burst rate timing as fast as 5-3-3-3. This means that reading the first element of data takes five clock cycles, containing four wait-states, with the next three elements each taking three.

DRAM speed improvements have historically come from process and photolithography advances. More recent improvements in performance however have resulted from changes to the base DRAM architecture that require little or no increase in die size. Extended Data Out (EDO) memory is an example of this.

EDO DRAM

Extended Data Out DRAM comes in 70ns, 60ns and 50ns speeds. 60ns is the slowest that should be used in a 66MHz bus speed system (i.e. Pentium 100MHz and above) and the Triton HX and VX chipsets can also take advantage of the 50ns version. EDO DRAM doesn't demand that the column be deactivated and the output buffer turned off before the next data transfer starts. It therefore achieves a typical burst timing of 5-2-2-2 at a bus speed of 66MHz and can complete some memory reads a theoretical 27% faster than FPM DRAM.

Burst EDO DRAM is an evolutionary improvement in EDO DRAM that contains a pipeline stage and a 2-bit burst counter. With the conventional DRAMs such as FPM and EDO, the initiator accesses DRAM through a memory controller. The controller must wait for the data to become ready before sending it to the initiator. BEDO eliminates the wait-states thus improving system performance by up to 100% over FPM DRAM and up to 50% over standard EDO DRAM, achieving system timings of 5-1-1-1 when used with a supporting chipset.

Despite the fact that BEDO arguably provides more improvement over EDO than EDO does over FPM the standard has lacked chipset support and has consequently never really caught on, losing out to Synchronous DRAM (SDRAM).

Memory - part 8

Direct RDRAM

Conventional DRAM architectures have reached their practical upper limit in operating frequency and bus width. With mass market CPUs operating at over 300MHz and media processors executing more than 2GOPs, it is clear that their external memory bandwidth of approximately 533 MBps cannot meet increasing application demands. The introduction of Direct Rambus DRAM (DRDRAM) in 1999 is likely to prove one of the long term solutions to the problem.

Direct RDRAM is the result of a collaboration between Intel and a company called Rambus to develop a new memory system. It is a totally new RAM architecture, complete with bus mastering (the Rambus Channel Master) and a new pathway (the Rambus Channel) between memory devices (the Rambus Channel Slaves). Direct RDRAM is actually the third version of the Rambus technology. The original (Base) design ran at 600MHz and this was increased to 700MHz in the second iteration, known as Concurrent RDRAM.

A Direct Rambus channel includes a controller and one or more Direct RDRAMs connected together via a common bus - which can also connect to devices such as micro-processors, digital signal processors (DSPs), graphics processors and ASICs. The controller is located at one end, and the RDRAMS are distributed along the bus, which is parallel terminated at the far end. The two-byte wide channel uses a small number of very high speed signals to carry all address, data and control information at up to 800MHz. The signalling technology is called Rambus Signalling Logic. Each RSL signal wire has equal loading and fan-out is routed parallel to each other on the top trace of a PCB with a ground plane located on the layer underneath. Through continuous incremental improvement signalling data rates are expected to increase by about 100MHz a year to reach a speed of around 1000MHz by the year 2001.

At current speeds a single channel is capable of data transfer at 1.6 GBps and multiple channels can be used in parallel to achieve a throughput of up to 6.4 GBps. The new architecture will be capable of operating at a system bus speed of up to 133MHz.

Problems with both the Rambus technology and Intel's chipset supporting it - the i820 - delayed DRDRAM's appearance until late 1999 - much later than had been originally planned. As a result of the delays Intel had to provide a means for the 820 chipset to support SDRAM DIMMs as well as the new Direct RDRAM RIMM module. A consequence of this enforced compromise and the need for bus translation between the SDRAM DIMMs and the 820's Rambus interface, was that performance was slower than when the same DIMMs were used with the older 440BX chipset! Subsequently, the component which allowed the i820 to use SDRAM was found to be defective and resulted in Intel having to recall and replace all motherboards with the defective chip and to also swap out the SDRAM that had been used previously with far more expensive RDRAM memory!

And Intel's Rambus woes didn't stop there. The company was repeatedly forced to alter course in the face of continued market resistance to RDRAM and AMD's continuing success in embracing alternative memory technologies. In mid-2000, its 815/815E chipsets were the first to provide support for PC133 SDRAM and a year later it revealed that its forthcoming i845 chipset would provide support for both PC 133 SDRAM and DDR-DRAM on Pentium 4 systems.

Why Should A PC Be Valeted?

Through everyday use, PC's accumulate dirt, dust, grime and germs. There are two major contributors to this - the people that use them (The Human Element) and the machines themselves (The Mechanical Element).

We will start with the Mechanical Element.

On every PC, there are air vents and cooling fans. The area within the casing of a computer gets hot, so fans are used to suck cool air into the machine to keep the temperature low. This prevents overheating. However, the problem is this: when the fans breath in cool air, they are also breathing in the dust and paper particles that are all around us - and more so if we work in an office. These particles settle on the fan itself, and other vital components. The dust and dirt build up, and start to clog the fan, reducing its effectiveness and creating noise. This means that vital components - such as the processor - the brain of the PC - are subject to overheating. Not to mention the possibility of the buildup of dust causing components to short out by static electricity.

In essence, the procedures in place to protect the PC are slowly destroying it...

We'll move on to the Human Element - you and me. Right now, you are at your machine, perhaps with one hand on the keyboard and one hand on the mouse. Or perhaps holding a bag of crisps, or an apple if you are healthier! But think of the germs that are currently on your hands. The crumbs that slip between the keys as you type. The apple juice residue that clings to the keys, making them sticky. These become breeding grounds for germs - so much so, that research has proved that there are 400x more germs per square inch on your keyboard than in your toilet bowl. Disgusting!

But think about it. How often does your toilet bowl get cleaned? Regularly. How often does your keyboard get cleaned - but not just cleaned - sanitised? Now there's food for thought. Not to mention the swabs that have been taken from computer keyboards

that have shown up hair, skin and nail particles, food remnants and insects! All lurking and rotting half a centimeter below where your fingers are now!

Yes, right now, the PC that you are working at now could be an overheating, germ infested, food riddled machine on the verge of mechanical breakdown!

It is for this reason that CompuClean offers commercial and domestic customers alike the Full System Valet. A comprehensive, all inclusive system 'makeover', getting to the root of the problems - completely removing the dirt and dust build-up from within the PC's casing. Meticulous cleaning of the keyboard - not just on the surface, but underneath too. Complete removal of the greasy fingerprints that mar the screen that you are looking at. And finally, sanitisation of the mouse. Is this a necessary service? Well, think of that word - service. Do you service your car? Yes. Why? Not because it is broken - no, but to keep it in good working order, and to prevent it from breaking down. The same is true with computer valeting - it's all about preventative maintenance. Regularly valeting your PC so that it doesn't break down.

How to Install a Front Loading Drive - part 2

Installing a CD-ReWriter

By far the most common 5.25in external drives are optical drives of one sort or another:

CD-ROM
DVD-ROM
CD-ReWriter
DVD-ReWriter

Installation procedure and issues are similar for each type of drive, and this tutorial is going to illustrate them in the context of installing a CD-ReWriter.

Configuring the drive

Select operation of the CD-ReWriter as an IDE master or slave, or for cable select, via the configuration jumper at the rear of the unit.
In this case the drive's factory setting is as a Master. To configure the drive as a Slave, move the jumper to the middle set of pins, leaving the other pins uncovered. To change the drive for Cable Select, move the jumper to the left set of pins.
This particular drive has shipped from the factory with no DMA jumper installed. The empty pins mean the drive is set to Ultra DMA, a setting that will work in most cases. However, the default Ultra DMA setting may be inappropriate for some older motherboards, causing the computer to hang or crash. If this happens, the setting may be changed to Multiword DMA mode by jumpering the two pins just to the left of the configuration jumper.
The Cable Select jumper position sets the drive to use the CSEL signal from the IDE interface for configuration. This signal automatically selects the correct Master/Slave setting. However, use of CSEL require that you have: a computer that supports CSEL a special CSEL cable for IDE connector. With Cable Select, the Master and Slave designations are determined not by jumpers, but by the actual connectors on the CSEL cable. The connectors are identified as Master or Slave. Note that if any device is jumpered as Cable Select, then both devices on that cable must be jumpered in the same way.

Memory - part 5

SDRAM

The more recent Synchronous DRAM memory works quite differently from other memory types. It exploits the fact that most PC memory accesses are sequential and is designed to fetch all the bits in a burst as fast as possible. With SDRAM an on-chip burst counter allows the column part of the address to be incremented very rapidly which helps speed up retrieval of information in sequential reads considerably. The memory controller provides the location and size of the block of memory required and the SDRAM chip supplies the bits as fast as the CPU can take them, using a clock to synchronise the timing of the memory chip to the CPU's system clock.

This key feature of SDRAM gives it an important advantage over other, asynchronous memory types, enabling data to be delivered off-chip at burst rates of up to 100MHz. Once the burst has started all remaining bits of the burst length are delivered at a 10ns rate. At a bus speed of 66MHz SDRAMs can reduce burst rates to 5/1/1/1. The first figure is higher than the timings for FPM and EDO RAM because more setting up is required for the initial data transfer. Even so, there's a theoretical improvement of 18% over EDO for the right type of data transfers.

However, since no reduction in the initial access is gained, it was not until the release of Intel's 440BX chipset, in early 1998, that the benefit of 100MHz page cycle time was fully exploited. However, even SDRAM cannot be considered as anything more than a stop-gap product as the matrix interconnection topology of the legacy architecture of SDRAM makes it difficult to move to frequencies much beyond 100MHz. The legacy pin function definition - separate address, control and data/DQM lines - controlled by the same clock source leads to a complex board layout with difficult timing margin issues. The 100MHz layout and timing issues might be addressed by skilful design, but only through the addition of buffering registers, which increases lead-off latency and adds to power dissipation and system cost.

Beyond 100MHz SDRAM, the next step in the memory roadmap was supposed to have been Direct Rambus DRAM (DRDRAM). According to Intel, the only concession to a transition period was to have been the S-RIMM specification, which allows PC100 SDRAM chips to use Direct RDRAM memory modules. However, driven by concerns that the costly Direct RDRAM would add too much to system prices, with the approach of 1999 there was a significant level of support for a couple of transitionary memory technologies.

PC133 SDRAM

Although most of the industry agrees that Rambus is an inevitable stage in PC development, PC133 SDRAM is seen as a sensible evolutionary technology and one that confers a number of advantages that make it attractive to chip makers unsure of how long interest in Direct RDRAM will take to materialise. Consequently, in early 1999, a number of non-Intel chipset makers decided to release chipsets that supported the faster PC133 SDRAM.

PC133 SDRAM is capable of transferring data at up to 1.6 GBps - compared with the hitherto conventional speeds of up to 800 MBps - requires no radical changes in motherboard engineering, has no price premium on the memory chips themselves and has no problems in volume supply. With the scheduled availability of Direct RDRAM reportedly slipping, it appeared that Intel had little option than to support PC133 SDRAM, especially given the widespread rumours that chipset and memory manufacturers were working with AMD to ensure that their PC133 SDRAM chips will work on the fast bus on the forthcoming K6-III processor.

At the beginning of 2000, NEC begun sampling 128MB and 256MB SDRAM memory modules utilising the company's unique performance-enhancing Virtual Channel Memory (VCM) technology, first announced in 1997. Fabricated with an advanced 0.18-micron process and optimised circuit layout and compliant with the PC133 SDRAM standard, VCM SDRAMs achieve high-speed operation with a read latency of 2 at 133MHz (7.5ns) and are package-and pin-compatible with standard SDRAMs.

The VCM architecture increases the memory bus efficiency and performance of any DRAM technology by providing a set of fast static registers between the memory core and I/O pins, resulting in reduced data access latency and reduced power consumption. Each data request from a memory master contains separate and unique characteristics. With conventional SDRAM multiple requests from multiple memory masters can cause page trashing and bank conflicts, which result in low memory bus efficiency. The VCM architecture assigns virtual channels to each memory master. Maintaining the individual characteristics of each memory master's request in this way enables the memory device to be able to read, write and refresh in parallel operations, thus speeding-up data transfer rates.

Continuing delays with Rambus memory as well as problems with its associated chipsets finally saw Intel bow to the inevitable in mid-2000 with the release of its 815/815E chipsets - its first to provide support for PC133 SDRAM.

Interfaces - part 5

PCI-X

PCI-X v1.0, a high performance addendum to the PCI Local Bus specification co-developed by IBM, Hewlett-Packard, and Compaq - normally competitors in the PC server market - was unanimously approved by the Peripheral Component Interconnect Special Interest Group (PCI SIG) in the autumn of 1999. Fully backward compatible with standard PCI, PCI-X was seen as an immediate solution to the increased I/O requirements for high-bandwidth enterprise applications such as Gigabit Ethernet, Fibre Channel, Ultra3 SCSI and high-performance graphics.

PCI-X not only increases the speed of the PCI bus but also the number of high-speed slots. With the current design, PCI slots run at 33MHz and one slot can run at 66 MHz. PCI-X doubles the current performance of standard PCI, supporting one 64-bit slot at 133MHz, for an aggregate throughput of 1 GBps. The new specification also features an enhanced protocol to increase the efficiency of data transfer and to simplify electrical timing requirements, an important factor at higher clock frequencies.

For all its performance gains, PCI-X was positioned as an interim technology while the same three vendors develop a more long-term I/O bus architecture, referred to as Future I/O. While of potential use throughout the entire computer industry, the initial application of PCI-X was expected to be in server and workstation products, embedded systems and data communication environments.

The symbolism of a cartel of manufacturers making architectural changes to the PC server without consulting Intel is seen as being a significant development. At the heart of the dispute is who gets control over future server I/O technology. The PCI-X faction - already wary of Intel's growing dominance in the hardware business - hoped to wrest some control by developing and defining the next generation of I/O standards, which they hope Intel will eventually support. Whether this would succeed - or merely generate a standards war - was a moot point since the immediate effect was merely to provoke Intel into leading another group of vendors in the development of rival I/O technology, which they referred to as "Next Generation I/O" (NGIO).

In 2002 PCI-X 2.0 emerged, initially doubling and ultimately promising to quadruple the speed of PCI-X. Its longevity contributed to the path to PCI's eventual successor being a bumpy one.

PCI Express

By the summer of 1999 the proponents of Future I/O and NGIO had called a truce and agreed to merge the two technologies into a new specification. Originally, this went by the working name of System I/O. However, by the end of the year it had been renamed InfiniBand. In the end the technology - which would have required the industry to adopt new hardware and software - proved just a little too revolutionary for most computing companies to feel comfortable about adopting and by the end of 2001 it had pretty much been relegated to a niche market.

In the summer of 2001 Intel had signalled that the writing was on the wall for Infiniband when it developed yet another technology, which it called Third-Generation Input/Output (3GIO). Also known as Arapahoe, this was adopted by the PCI SIG in the summer of 2001. Early the following year, ownership of 3GIO was transferred to the PCI-SIG where it was re-named the PCI Express Architecture. Finally the industry had reached a decision on PCI's successor. It is one which represents a more evolutionary approach than some of the schemes that had been proposed earlier, the move to PCI Express being expected to be similar to the ISA/EISA to PCI transition experienced in the early 1990s.

The PCI Express Architecture defines a flexible, scalable, high-speed, serial, point-to-point, hot pluggable/hot swappable interconnect that is software-compatible with PCI. Unlike its predecessor, PCI Express is a serial point-to-point interconnect system, similar to AMD's HyperTransport technology. Serial bus architectures deliver more bandwidth per pin than parallel bus architectures and scale more easily to higher bandwidths. They allow for a network of dedicated point-to-point links between devices rather than the multi-drop scheme used by parallel bus architectures. This eliminates the need for bus arbitration, provides deterministic low latency and greatly simplifies hot plug/hot swap system implementations. It is anticipated that one consequence of this will be a reduction in board area of up to 50%.

A PCI Express (PCX) bus topology contains a Host Bridge and several endpoints (the I/O devices). Multiple point-to-point connections introduce a new element, the switch, into the I/O system topology. This provides fanout capability and enables a series of connectors for add-in, high performance I/O. The switch is a logical element that may be implemented within a component that also contains a host bridge, or it may be implemented as a separate component.

A PCX interface comprises two pairs of wires, referred to as a lane, and a single PCX lane is known as a 1x interface. Lanes may be aggregated, and a maximum possible 32 data lanes provides total bandwidth of 16 GBps, sufficient to support the control plane and data plane demands of communications systems well into the foreseeable future. Moreover, it is an architecture that allows real-time data - such as streamed video or audio - to be "tagged" so that an I/O system can prioritise its flow throughout the platform.

Whilst PCI Express is positioned as a complementary technology to PCI and PCI-X, it's intended to replace AGP. Indeed, one of its initial targeted applications is for use as a graphics I/O attach point. The first generation of PCI Express Architecture provides up to 8 GBps of dedicated bi-directional bandwidth, enough to move High Definition (HD) video streams between the system memory and the hard drive out to the graphics card and back to the memory/hard drive. PCI Express X16 graphics supports the rendering of multiple HD (720p) video streams at up to twice the frame-rate of AGP 8X.

The first chipsets to provide support for PCI Express - codenamed Alderwood and Grantsdale - were announced in summer of 2004, with complete PCs emerging shortly after.

CPU Technology - part 6

SpeedStep

Just a few weeks after its launch of the Dixon, Intel demonstrated a revolutionary new mobile processor technology that was expected to close the performance "gap" between mobile PCs and their historically higher performance desktop counterparts. The demonstration was of a dual-mode mobile processor technology - codenamed "Geyserville" - that allowed a mobile PC user to operate at a higher frequency when plugged into a wall outlet and automatically switch to a lower power and frequency when running on battery, conserving battery life. The technology was subsequently introduced aboard mobile 600MHz and 650MHz Pentium III processors in early 2000 - under the name "SpeedStep".

SpeedStep technology offers mobile users two performance modes: Maximum Performance mode and Battery Optimised mode. The system by default automatically chooses which mode to run in, depending on whether the computer is running on batteries or mains power. When running in Battery Optimised Mode, the processors ran at 500MHz and 1.35V, significantly lowering CPU power consumption and consequently preserving battery life. When a user plugged into an AC outlet, the notebook automatically switched to Maximum Performance Mode, increasing the voltage to 1.6V and the speed to the maximum the processor was capable of. These transitions happen in only 1/2000th of a second - so fast they are completely transparent to users, even if they occur in the middle of performance intensive applications such as; running performance-intensive applications such as playing a DVD movie. Users also have the freedom to select the Maximum Performance Mode even while running on batteries. Making that switch is as easy as clicking an icon at the bottom of the screen, with no reboot required.

Intel has developed both the hardware and software components to make the SpeedStep technology work seamlessly, including the system BIOS, end user interface software, switch control ASIC and support in the chipset. No change to operating systems or software applications is needed in order to take advantage of the technology.

Mobile Duron

Until 2001 all of AMD's mobile CPUs had been based on the K6 design. The company's Athlon/Duron family of processors had already succeeded in gaining market share from Intel in the desktop arena, in the performance and value sectors respectively. Early in 2001 AMD signalled their intent to similarly challenge Intel's domination of the mobile CPU market segment.

Based on the Duron Spitfire processor core, the Mobile Duron had similar features to its non-mobile counterpart, utilising a 100MHz double-pumped system bus (200MHz effective throughput), 128KB of on-chip L1 cache and 64KB of on-chip L2 cache. The chip's core operates at 1.4V - compared with the 1.6V of the desktop version - which equates to a battery life of between two and three hours. The CPU was initially launched at speeds of 600MHz and 700MHz.

It was not long before the ante in the mobile processor sector was raised. When Intel announced its 0.13-micron Pentium III Tualatin core - intended primarily for the mobile sector - in mid-2001, AMD responded with its 0.13-micron Morgan and Palomino processor cores. These are differentiated by the size of their L2 cache, 64KB and 256KB respectively. The Morgan core is used in value notebooks, under the Duron brand name, while the Palomino core is featured in more expensive high-performance notebooks under the new Athlon 4 branding.

By the spring of 2002 the Mobile Duron CPU was available in various speed grades to 1.2GHz.

How to Install a Front Loading Drive - part 1

This tutorial will take you through the steps involved in installing both front-loading 5.25in and 3.5in drives - specifically a CD-ReWriter and floppy disk drive - covering each of the following:

configuring the drives
mounting the drives
making the connections
configuring BIOS
installing associated software.

The tutorial also covers the installation of associated software and performance optimisation of the CD-ReWriter and alternatives to the ageing floppy disk drive technology.

Drive bay terminology

A drive bay is an area within a PC's system case designed to accommodate drive devices, such as a hard disk drive, floppy drive, CD-ROM drive, tape drive etc. There are two types, external and internal, the former allowing a drive to be accessed from the exterior, the latter requiring that the system case be opened up.

The ATX form factor - the predominant form factor since the late 1990s - accommodates two external drive bay sizes, 5.25in and 3.5in.

These dimensions relate to the width of the magnetic disk media these bays were originally designed to accommodate, and not the width of the bays themselves. In fact, standard 3.5in and 5.25in drives are 4in and 5.75in (excluding faceplate) wide, respectively. 5.25in drives are often referred to as "half-height" drives, a term that harps back to the original IBM PC, which came equipped with up to two "full-height" floppy disk drives measuring 3.25in in height.

A modern-day ATX midi-tower system case will typically have 3/4 external 5.25in drive bays and a couple of external 3.25in bays, as well as an internal card cage that accommodate a number of additional 3.25in drives.

AJP - M722 Review

Sitting at the lower end of the sub-notebook price range, the AJP M722 may lack a little in build quality, but makes up for it with its performance and, in particular, its battery life. Fitted with a Mobile Pentium III 750MHz chip and 128MB of main memory, the M722 is no slouch in the performance stakes.

Despite the price, the M772 has an excellent, crystal clear 12.1-inch TFT screen, powered by a 4MB ATI Rage Mobility chip, which gives the display a native resolution of 1024 x 768 pixels. You also get a 12GB hard disk; a 56Kbps modem and Ethernet adapter built in, while proprietary and USB connectors are used for the 24-speed CD-ROM drive and the floppy drive respectively.

But what lets the M722 down is its keyboard. It doesn't seem to be particularly well built; the whole of the keyboard deck has a lot of flex and isn't particularly responsive. On the plus side, the backspace key is a decent size, and there are five programmable 'Easy Start' keys placed above the keyboard. Windows 2000 Professional is installed by default, and you also get a copy of Microsoft Works 2000 pre-installed.

The AJP M722 comes with a high-capacity battery, which gives it a very respectable working time of nearly three and a half hours. This larger battery does, however, increase the weight of the system, taking it up to the 2kg mark. This is a small sacrifice compared to the gain in battery life, though.

Despite its poor keyboard, the M722's processing power and battery life make it worthy of serious consideration at this price.

AJP - M722 price

1,585 + VAT

AJP: 020 82089744

How to Install a Front Loading Drive - part 8

Mounting the drive

As will have been seen earlier, the system case we're using has a 3.5in bay assembly capable of holding two 3.5in devices. This may be removed by unscrewing the two silver thumbscrews located at the bottom and sliding the drive bay assembly out.
We're going to install the floppy drive in the bottom drive bay and then slide the whole assembly back into the case and fasten the thumbscrews.
If you don't have a removable assembly, simply slide the drive into an available 3.5in bay and secure with screws on either side in the normal way. If you have to, a 3.5in drive can be fit into a 5.25in drive bay using a 3.5in to 5.25in mounting kit. Generally these will include a mounting bracket, face plate, power adapter and all necessary screws.
Replace the top half of the front bezel and make sure both the CD-ReWriter and floppy disk drive are positioned flush with its front edge.

In recognition of the trend towards systems being increasingly available in colours other than traditional beige, a number of system case manufacturers are selling front-loading drive bezels in colours such as black or grey, or in steel or aluminium metallic finishes that match their range of cases. Moreover, a number of optical equipment manufacturers are also producing drives in more than a single colour. Kustom PCs is both a retailer - based in Ayr, Scotland - and online store who bill themselves as seeking to "strive to build the best looking and best performing tailored systems for the user who demands a little more". It is they who supplied me with many of the components featured in this tutorial. The PCTechGuide is not in the habit of promoting particular products or dealers. However, so outstanding have I found the level of service provided by Kustom PCs, that I'm making a rare exception in their case: their web site is straight forward, well organised, illustrative and fast their delivery charge policy is the fairest I've encountered their range of products is extensive both their pre and post sales service has been exemplary.

Memory - part 9

SIMMs

Memory chips are generally packaged into small plastic or ceramic dual inline packages (DIPs) which are themselves assembled into a memory module. The single inline memory module or SIMM is a small circuit board designed to accommodate surface-mount memory chips. SIMMs use less board space and are more compact than previous memory-mounting hardware.

Memory modules evolved from the need of saving motherboard space and effortless memory expansion. Instead of plugging in 8 or 9 single DRAM DIP chips, only one additional memory module was needed to increase the memory of the computer. The SIMM was the successor of SIPP memory (Single In-line Pin Package), which was used in 80286 systems. SIPP's 30 pins often bent or broke during installation, leading to a SIMM's contact plate design.

By the early 1990s the original 30-pin SIMM had been superseded by the 72-pin variety. These supported 32-bit data paths, and were originally used with 32-bit CPUs.

A typical motherboard of the time offered four SIMM sockets capable of taking either single-sided or double-sided SIMMs with module sizes of 4, 8, 16, 32 or even 64MB. With the introduction of the Pentium processor in 1993, the width of the data bus was increased to 64-bits. When 32-bit SIMMs were used with these processors, they had to be installed in pairs, with each pair of modules making up a memory bank. The CPU communicated with the bank of memory as one logical unit.

DIMMs

By the end of the millennium, as memory subsystems standardised around an 8-byte data interface, the Dual In-line Memory Module (DIMM) had replaced the SIMM as the module standard for the PC industry. DIMMs have 168 pins in two (or dual) rows of contacts; one on each side of the card. With the additional pins a computer can retrieve information from DIMMs, 64 bits at a time instead of the 32- or 16-bit transfers that are usual with SIMMs.

Some of the physical differences between 168-pin DIMMs and 72-pin SIMMs include: the length of module, the number of notches on the module, and the way the module installs in the socket. Another difference is that many 72-pin SIMMs install at a slight angle, whereas 168-pin DIMMs install straight into the memory socket and remain completely vertical in relation to the system motherboard. Importantly, and unlike SIMMs, DIMMs can be used singly and it is typical for a modern PC to provide just one or two DIMM slots.

The 3.3 volt unbuffered DIMM emerged as the favoured standard. This allows for SDRAM, BEDO, EDO and FPM DRAM compatibility as well as x64 and x72 modules with parity and x72 and x80 modules with ECC and takes advantage of the left key position to establish a positive interlock so that the correct DIMMs are inserted in the correct position.

The advent of DDR and DDR2 SDRAM led to different variants of DIMM packaging, as did the Small Outline (SO) form factor used in notebook PCs. By 2005 the most common types of DIMMs were:

72-pin-DIMMs, used for SO-DIMM
144-pin-DIMMs, used for SO-DIMM
168-pin-DIMMs, used for SDRAM
184-pin-DIMMs, used for DDR SDRAM
240-pin-DIMMs, used for DDR2 SDRAM

DDR SDRAM DIMMs can be differentiated from SDRAM DIMMs by the number of notches, the former having one, the latter two.

RIMMs

With the introduction of Direct RDRAM (DRDRAM) in 1999 came the RIMM module (the name is not an acronym, but a trademark of Rambus Inc.). RIMM connectors have a form factor similar to DIMMs and fit within the same board area as the footprint for a DIMM connector. They have 184 pins compared to a DIMM's 168, but use the same socket specification as a standard 100MHz DIMM. A PC's BIOS will be able to determine what type of RAM is fitted, so 100MHz SDRAM modules should work in a RIMM-compatible system. However, systems can't use RIMMs unless both BIOS and the chipset support it. In the case of the latter, after many delays this finally arrived in the shape of Intel's 820 chipset in November 1999. SO-RIMM modules - which use the same form factor as small-outline SO-DIMMs - are available as one-to-eight RDRAM devices.

The major elements to a Rambus memory subsystem include a master device that contains the Rambus ASIC Cell (RAC) and Rambus Memory Controller (RMC), Direct Rambus Clock Generator (DRCG), RIMM connectors, RIMM memory modules, and RIMM continuity modules. The RIMM connector is an integral component in the Rambus Channel by providing the mechanical and electrical interface and signal integrity for the high speed Rambus signals as they move from the master ASIC to the appropriate RDRAM memory device component and vice versa. Since the Rambus Channel is a terminated transmission line, the channel must be electrically connected from ASIC to termination resistors. The net effect is that all RIMM connectors need to be populated with either a RIMM memory module or a RIMM continuity module to insure the electrical integrity of the Rambus Channel.

Motherboards - part 7

CPU interfaces

The PC's ability to evolve many different interfaces allowing the connection of many different classes of add-on component and peripheral device has been one of the principal reasons for its success. The key to this has been standardisation, which has promoted competition and, in turn, technical innovation.

The heart of a PC system - the processor - is no different in this respect than any other component or device. Intel's policy in the early 1990s of producing OverDrive CPUs that were actually designed for upgrade purposes required that the interface by which they were connected to the motherboard be standardised. A consequence of this is that it enabled rival manufacturers to design and develop processors that would work in the same system. The rest is history.

In essence, a CPU is a flat square sliver of silicon with circuits etched on its surface. This chip is linked to connector pins and the whole contraption encased some form of packaging - either ceramic or plastic - with pins running along the flat underside or along one edge. The CPU package is connected to a motherboard via some form of CPU interface, either a slot or a socket. For many years the socket style of CPU was dominant. Then both major PC chip manufacturers switched to a slot style of interface. After a relatively short period of time they both changed their minds and the socket was back in favour!

The older 386, 486, classic Pentium and Pentium MMX processors came in a flat square package with an array of pins on the underside - called Pin Grid Array (PGA) - which plugged into a socket-style CPU interface on the motherboard. The earliest such interface for which many motherboards and working systems remain to this day - not least because it supported CPUs from so many different chip manufacturers - is Socket 7. Originally developed by Intel as the successor to Socket 5, it was the same size but had different electrical characteristics including a system bus that ran at 66MHz. Socket 7 was the interface used by most Pentium systems from the 75MHz version and beyond.

Socket 8 was developed for Intel's Pentium Pro CPU - introduced in late 1995 - and specifically to handle its unusual dual-cavity, rectangular package. To accommodate L2 cache - in the package but not on the core - this contained up to three separate dice mounted on a small circuit board. The complicated arrangement proved extremely expensive to manufacture and was quickly abandoned.

With the introduction of their Pentium II CPU, Intel switched to a much cheaper solution for packaging chips that consisted of more than a single die. Internally, the SECC package was really a circuit board containing the core processor chip and cache memory chips. The cartridge had pins running along one side which enabled it to be mounted perpendicularly to the motherboard - in much the same way as the graphics or sound card is mounted into an expansion slot - into an interface that was referred to as Slot 1. The up to two 256KB L2 cache chips ran at half the CPU speed. When Intel reverted - from the Pentium III Coppermine core - to locating L2 cache on the processor die, they continued to use cacheless Slot 1 packaging for a while for reasons of compatibility.

Pentium II Xeon's - unlike their desktop counterparts - ran their L2 cache at full clock speed. This necessitated a bigger heatsink which in turn required a taller cartridge. The solution was Slot 2, which also sported more connectors than Slot 1, to support a more aggressive multi-processor protocol amongst other features.

When Intel stopped making its MMX processor in mid-1998 it effectively left the Socket 7 field entirely to its competitors, principally AMD and Cyrix. With the co-operation of both motherboard and chipset manufacturers their ambitious plans for extending the life of the "legacy" form factor was largely successful.

AMD's determination to match Intel's proprietary Slot 1 architecture on Socket 7 boards was amply illustrated by their 0.25-micron K6-2 processor, launched at the end of May 1998, which marked a significant development of the architecture. AMD referred to this as the "Super7" platform initiative, and its aim was to keep the platform viable throughout 1999 and into the year 2000. Developed by AMD and key industry partners, the Super7 platform supercharged Socket 7 by adding support for 100MHz and 95MHz bus interfaces and the Accelerated Graphics Port (AGP) specification and by delivering other leading-edge features, including 100MHz SDRAM, USB, Ultra DMA and ACPI.

When AMD introduced their Athlon processor in mid-1999 they emulated Intel's move away from a socket-based CPU interface in favour of a slot-based CPU interface, in their case "Slot A". This was physically identical to Slot 1, but it communicated across the connector using a completely different protocol - originally created by Digital and called EV6 - which allowed RAM to CPU transfers via a 200MHz FSB. Featuring an SECC slot with 242 leads, Slot A used a Voltage Regulator Module (VRM), putting the onus on the CPU to set the correct operating voltage - which in the case of Slot A CPUs was a range between 1.3V and 2.05V.

Slot-based processors are overkill for single-chip dies. Consequently, in early 1999 Intel moved back to a square PGA packaging for its single die, integrated L2 cache, Celeron range of CPUs. Specifically these used a PPGA 370 packaging, which connected to the motherboard via a Socket 370 CPU interface. This move marked the beginning of Intel's strategy for moving its complete range of processors back to a socket-based interface. Socket 370 has proved to be one of the more enduring socket types, not least because of the popularity of the cheap and overclockable Celeron range. Indeed, Intel is not the only processor manufacturer which produces CPUs that require Socket 370 - the Cyrix MIII (VIA C3) range also utilising it.

The sudden abandonment of Slot 1 in favour of Socket 370 created a need for adapters to allow PPGA-packaged CPUs to be used in Slot 1 motherboards. Fortunately, the industry responded, with Abit being the first off the mark with its original "SlotKET" adapter. Many were soon to follow, ensuring that Slot 1 motherboard owners were not left high and dry. A Slot 1 to Socket 370 converter that enables Socket 370-based CPUs to be plugged into a Slot 1 motherboard was also produced. Where required, these converters don't just provide the appropriate connector, they also make provision for voltage conversion.

Unfortunately users were more inconvenienced by Intel's introduction of the FC-PGA (Flip Chip-Pin Grid Array) and FC-PGA2 variants of the Socket 370 interface - for use with Pentium III Coppermine and Tualatin CPUs respectively - some time later. The advantage with this packaging design is that the hottest part of the chip is located on the side that is away from the motherboard, thereby improving heat dissipation. The FC-PGA2 package adds an Integral Heat Spreader, improving heat conduction still further. Whilst FC-PGA and FC-PGA2 are both mechanically compatible with Socket 370, electrically they're incompatible and therefore require different motherboards. Specifically, FC-PGA processors require motherboards that support VRM 8.4 specifications while FC-PGA2 processors require support for the later VRM 8.8 specifications.

Like Intel's Slot 1, AMD's proprietary Slot A interface was also to prove to be relatively short-lived. With the advent of the Athlon Thunderbird and Spitfire cores, the chipmaker followed the lead of the industry leader by also reverting to a PPGA-style packaging for its new family of Athlon and Duron processors. This connects to a motherboard via what AMD calls a "Socket A" interface. This has 462 pin holes - of which 453 are used by the CPU - and supports both the 200MHz EV6 bus and newer 266MHz EV6 bus. AMD's subsequent Palomino and Morgan cores are also Socket A compliant.

With the release of the Pentium 4 in late 2000, Intel introduced yet another socket to its line-up, namely Socket 423. Indicative of the trend for processors to consume ever decreasing amounts of power, the PGA-style Socket 423 has a VRM operational range of between 1.0V and 1.85V.

Socket 423 had been in use for only a matter of months when Intel muddied the waters still further with the announcement of the new Socket 478 form factor. The principal difference between this and its predecessor is that the newer format socket features a much more densely packed arrangement of pins known as a micro Pin Grid Array ( PGA) interface, which allows both the size of the CPU itself and the space occupied by the interface socket on the motherboard to be significantly reduced. Socket 478 was introduced to accommodate the 0.13-micron Pentium 4 Northwood core, launched at the beginning of 2002.

In the autumn of 2003 AMD brought two versions of their K8 architecture to the desktop market, branded the Athlon 64 and the Athlon 64 FX. The new chips signalled the end of the line for the venerable Socket A CPU interface. The Athlon 64 saw the introduction of Socket 754 and has a single-channel integrated memory controller. The Athlon 64 FX used the Opteron's dual-channel memory controller design and the same Socket 940 interface.

The summer of 2004 saw the Athlon 64 line converged to a new platform, Socket 939. Importantly, this allowed both the consumer and high-end models to use unbuffered memory in a dual channel configurations.

At about the same time, Intel unveiled major changes in its platform technology, including new PCI Express compatible chipsets and the innovative LGA775 CPU interface (also referred to as Socket T). The first Pentium 4 processors to use the company's recently announced "processor numbers" model naming scheme - the Prescott-based 520 to 560 CPUs - all used the new platform technology.

Tips to Fix Cable Internet Issues

Cable modems can lose their connection for two different reasons: power loss or signal loss. Each one can be prevented in different ways but the fixes are similar. Additionally, personally-owned equipment can block a connection inadvertently. By evaluating the situation, there are easy ways to get back up and running.

Power Issues

If a modem loses power often, the fixes are simple. The first thing is ensure the modem is connected to an outlet that is not overloaded by many devices. Additionally if the outlet is on an overloaded circuit, that can also cause power loss. Changing outlets is the fastest fix but the modem can be connected to a backup battery. This would ensure power is regulated from spikes and will stay up with battery power.

Signal Issues

The signal that comes into cable modems must be within a certain range in order to function. The signal constantly fluctuates but as long as it does not go too high or too low, the modem will operate with no issues. The signal to a modem can go out due to a loss of signal to the house, a signal that is too weak or too strong, or finally due to faulty equipment blocking the signal.

The best way to determine if a splitter is causing a signal loss is to replace it with a new digital splitter. These have circuitry in them, allowing them to split a modem signal. Regular splitters from the store will not work and correct ones should be obtained from the cable company. If replacing the splitter fixes it, the problem should be gone.

If the signal is coming in too high or low, a splitter may aggravate the issue. In this case, bypassing the splitter with the modem is the best step to take. If it works without the splitter (after replacing it) then the signal strength is an issue. More than likely a technician appointment would be needed by the cable company.

Equipment Issues

Sometimes an internet connection can be lost due to equipment attached to the modem. If the modem is functioning properly but the computer cannot get online, more than likely there is a piece of hardware blocking the connection. In most cases the issue is a router that's lost its sync with the modem. To restore the connection simply power off both devices and then power them back on with the modem first and then the router 30 seconds later.

If there is no router in the house or the reset above hasn't fixed it, the issue would then rest on the computer itself. Most security software auto-updates and can cause a loss of connection. Additionally, a virus or infection of the computer can cause it to lose internet. A reboot of the machine should be tried first, followed by a full system scan if needed. All cable modems have light patterns on them to indicate what they are doing.

By learning these patterns and trying some of these simple troubleshooting steps, there is a large chance a loss of internet can be restored in a matter of minutes. This is a much better option than waiting on hold for a long time and possibly scheduling unnecessary appointments with the cable company. Finally, these steps can help ensure the connection has as high of an uptime as possible

CPU Technology - part 11

Sonoma

Together with the explosive worldwide growth in WLAN hotspots, the unveiling of Intel's second-generation mobile technology platform in January 2005 is expected to lead to the completion of the notebook PC's transition from a portable to a wireless device, fuelled by the introduction of the Centrino brand two years earlier. Predictions are that the number of frequent WLAN hotspot users will have increased from less than 1 million in 2002 to over 30 million by 2006.

Sonoma improves on each of Centrino's key mobile technologies, comprising:

the i915 Graphics and Memory Controller Hub (GMCH)
the IO Controller Hub (ICH) 6-M, and
the Intel PRO/Wireless 2915 a/b/g Network Interface Controller (NIC)
a number of new Pentium M processors.

The centrepiece of the Sonoma package is the 915 Express chipset, formerly codenamed Alviso, which provides the support for several new technologies expected to provide a foundation for notebook PCs for the next decade:

mobile PCI Express (PCIe) and ExpressCard technology
Serial Advanced Technology Attachment (SATA) interface
PCIe External Graphics (PEG) interface
Double Data Rate (DDR) memory, and
Intel High Definition (HD) Audio.

The new platform delivers both on CPU and graphics performance through scaling in core and bus frequencies as well as with microarchitecture enhancements including doubling processor cache size. The graphics performance improves by 2x over the previous generation platform. GMCH enables an enriched media experience through incorporation of Intel HD Audio and higher-speed interfaces.

The PCIe Mini Card replaces the Mini PCI card, typically used on the mobile motherboard for build-to-order optional functions. The ExpressCard module is a new add-in card that replaces the CardBus PC Card. Both of these new cards provide not only PCIe bus connectivity but also USB 2.0 connectivity through the same connector.

SATA is the evolution of the Parallel ATA bus for connecting mass storage (hard and optical drives) on mobile platforms initially upgrading the transfer rate from 133 MBps to 150 MBps with ability to scale to 300 MBps and 600 MBps in future. SATA is also friendly to mobile form factors since it needs a much smaller connector than parallel ATA.

To support PCIe, SATA, and Intel HD Audio, a newer cross-chip interconnect, Direct Media Interface (DMI), between the GMCH and the ICH, was developed. This upgraded the cross-chip transfer rate from 266 MBps to 2 GBps The DMI enables concurrent traffic and isochronous data transfer capabilities.

The new chipset supports next-generation memory technology by implementing the DDR2 specification, an evolutionary technology that extends first-generation DDR. The DDR2 specification allows increased clock rates over DDR while operating at 1.8V vs. 2.5V on earlier-generation technology.

Finally, the new platform's support for Intel HD Audio means significant improvements over AC'97 previous-generation integrated audio and sound cards. While the latter supports only six channels at 48 kHz/20-bit, Intel HD Audio hardware is capable of delivering the support and sound quality for up to eight channels at 192 kHz/32-bit quality and enables Dolby 5.1/7.1 surround sound audio out capability, which can be used with an SPDIF optical interface for component audio amplifiers.

In addition to the improvements afforded by the new chipset, there have also been changes to the wireless technology. As well as providing support for the 802.11a, 802.11b and 802.11g wireless networking standards, Sonoma's Intel PRO/Wireless 2915ABG NIC includes a coexistence solution that mitigates interference with wireless Bluetooth human interface devices (HIDs). Wireless connectivity is also enhanced with industry-standard WLAN security support and a simplified user interface.

Seven new Pentium M processors are available as part of the package. Formerly codenamed "Dothan", these 700 series chips retain the same basic design as the original Pentium M, but are manufactured on a 90nm process. At 84mm2 the die size remains in the same neighbourhood as the original Pentium M, even though the 700 series contains around 140 million transistors, most of which make up the 2MB L2 cache. The five CPUs that use the faster 533MHz FSB are identified by processor numbers that are divisible by ten. The top-of-range Pentium M 770 runs at 2.13 GHz. At the other end of the range, the Pentium 753 ULV (Ultra Low Voltage) version uses the 400MHz FSB and runs at 1.2 GHz.

Common Computer Monitor Display Problems

Unfortunately, computer monitor display problems can strike suddenly and without warning. One minute you re enjoying an intense session of World of Warcraft or a nice mild game of Solitaire, and the next minute your monitor is displaying weird colors or nothing at all. Here are some of the most common display problems, and potential causes:

Cascading Causes
While some computer monitor display problems are simple in nature and tend to have a single cause, many problems could be the result of several different malfunctions. When you re having a computer monitor problem, you ll need to take a series of steps to troubleshoot and diagnose the malfunction. If you re unable to determine why your monitor is having problems, you may need to consult a professional.

No Display
If your computer monitor doesn t display anything, you should try a couple of easy fixes. First, make sure the cords are fully connected and the power is on. If the power on indicator is lit and green, your computer monitor is receiving power and signal from your PC but having another type of problem. If the LED is lit but orange, the monitor isn t receiving signal from the PC, and you should check the cable connecting it to the PC. If the power LED isn t lit at all, the power cord may not be connected or the monitor may not be turned on.

Bizarre Patterns or Lines
If your computer monitor has bizarre patterns or lines, try jiggling the cord that connects the monitor to the PC. If the picture improves, check the connections at both ends. If they're both good, you simply need to replace the cable.

If jiggling the cable doesn't work, check your menu options. Try adjusting menus to see if any options affect the lines. Change one option at a time and test it to see if the display improves before moving on to the next option. If you attempt to adjust all the menu options and have no luck eliminating the lines, your monitor may be completely broken and you should consult a professional.

Stuck Pixels
An LCD computer monitor screen occasionally suffers from stuck pixels. If you see a black dot in the screen that doesn t change when the picture changes, you re looking at a stuck pixel. To attempt to unstick a pixel, cover the monitor with a soft cloth and use a pointy, but not sharp, object to rub the spot where the stuck pixel is located. Do this very, very gently. If you press too hard, you'll do permanent damage to your monitor.

Blurry Image
A blurry computer monitor has many potential causes and fixes, but some of the most common involve adjusting your settings. First, try adjusting your hard settings on the monitor menu itself. Next, try re-seating your cables or using different monitor cables to connect the PC and monitor. If that doesn t work, go into your computer s display settings and adjust the resolution, the refresh rate and the graphic acceleration functions. Finally, try re-installing your monitor drivers with the most updated drivers available on the manufacturer s Web site. If none of these fixes works, you need to consult a professional.

Image Is Dim
Dim computer monitor display problems usually have two causes: either the settings need to be adjusted, or the monitor is dying. Try adjusting the brightness settings in your monitor s menu. If that doesn t affect the monitor s brightness, you may need to consult a professional because your monitor s backlight may be going out and your monitor could be dying

The life expectancy of a PC

Many articles have been written regarding PC life expectancy but none of them really apply to the taxi booking and dispatch industry or any other industry where PCs are left switched on 24 Hours a day so let us just look at the raw data and extrapolate what we can from it.

Both Intel and AMD specify the expected life of a home/office PC CPU at 30,000 -50,000 hours at ambient temperatures. The life expectancy can be considerably shorter if the electronics are stressed in any way. That equates to 3-5 years. Most failures will be as a result of thermal stress and therefore to ensure the full 30-50,000 hours the PCs should be well ventilated and have the fans and filters checked and serviced every 3000 hours (approx 4 months). Everytime your PC CPU is operating above its ideal operating temperature it is ageing much faster.

Based on the assumption that most home office PCs are only switched on for 3-10 hours a day this makes the life expectancy 8-15 years. It also makes the fan/filter service interval at about 3 years which is when most people are thinking about upgrading to the lateset whizzo chipset or soundcard anyway.

So nearly everyone who consumes PCs are happy as technological development leaps forward faster than the failure rate of the PC components and therefore PCs tend to be scrapped or upgraded long before the hardware needs servicing or breaks down.

If we now look at an industry where the PC is required to work 24/7 most suppliers would recommend purpose designed fileservers for such a job. Fileservers are usually rack mounted in temperature controlled dust free cabinets (ours is). It is therefore not unfair to assume that such environments and the purpose built ruggedised machines may double the life expectancy of a CPU.

So lets go back to the booking and dispatch environment where the PC are left on permanently. The environment is very poor indeed. Most offices have incredible temperature variations between winter and summer, day and night.

Coupled with this the air is full of dust, exhaust soot and human detritus. On many sites I have found CPU fans and filters totally blocked after only 9 months of use. This will cause the CPU to operate at a higher temperature and therefore decrease the life expectancy to 150000 hours.

So assuming that you actually clean the fans and filters every 4 months.

You must still accept that the temperature controlled environment of most taxi offices is less than ideal. The longest you could expect trouble free operation of your PC would be a little over 3 years. Also assuming that you would want to change your PC long before it starts to play up and potentially corrupt your data or cause financial loss to your business you should be planning it at least 6 months before.

Now lets take the worst case scenario.

You place your PC on the floor in a dusty office, you leave it on 24/7 and nobody ever cleans out the fans or filters. After approx 9 months the PC is overheating in another 6 months the CPU will be malfunctioning, so after only 12-18 months you once lovely new PCs appear to be nearly scrap!! (sound familiar).

Even cleaning out the fans at this point will not reverse the thermal ageing process. In this scenario you should be ordering replacement PCs in a little over a year.

What is the answer

Well there is no real answer but knowledge and education are probably the best weapons against premature thermal aging and extending your PC life expectancy.

Protect your PC from elevated operating temperatures.

Firstly try to make sure the room temperature (the ambient temperature) does not exceed the recommended (IRO 18-22 degrees c). Coupled with this is to choose a PC manufacturer who does not skimp on the cooling arrangements and has designed a PC with extended operating hours in mind.

Some CPU cooling fans

can cost as much at 7.00 is they have ball bearings and thermal sensors. Other cheap ones have nylon bearings and only cost 90p.

You will often hear these cheaper fans making squeaks or rattles as the bearings fail. Once this happens your PC is aging much faster than normal. Avoid cheap knocked down PCs. If you have someone building PCs for you pay the extra money and have a larger than needed power supply fitted (it will run cooler). Also insist that the fans are expensive bearing fans with a 50000 hour or lifetime guarantee. Try and use machines with industrial 4inch fans and not the 1inch hobby fans fitted to most cheap PCs.

Temperature alarms

If your PC has CPU temperature warning alarms make sure these are set to the lowest recommended threshold to warn you if the cooling is failing. All Server PCs built by Diplomat have raid hard drives with built in thermal sensors, these trigger an email alert in the event of a hard drive failure or the PC has a temperature problem. This enables servicing to be proactive and not reactive.

Diplomat recommends

Diplomat recommends Dell optiplex computers. They have been designed for high usage business environments. They have 2 (yes two) large industrial 4 inch fans.

Due to the size and quality of these fans they rarely wear out or become blocked.

For more information go to www.diplomat.co.uk

Accept the life expectancy and plan ahead.

Even with perfect care and consideration you PC is not designed to last much longer than 3 years in a 24/7 environment.. You should plan your replacement schedule carefully and demote or retire mission critical PCs (such asSTN1) to less critical positions after about 2 years.

Moores law dictates that the replacement will be twice as fast or half the price so don t see this as a burden just accept it as a running cost.

Be philosophical

If you compare the life expectancy of family car and then compare it with a family car that is being used as a taxi 24/7 it will be less than half. This also applies to PCs in the same environment.

Ok its expensive or is it?

At around 600 for 1000 days work this means your computer costs you 60p a day. It works 24/7 never takes a lunch break or pulls a sickie. Its replacement in 3 years will cost less work faster and remember more. So all in all they are not such bad little critters after all, they just don t last forever..

Device Management

The path between the operating system and virtually all hardware not on the computer's motherboard goes through a special program called a driver. Much of a driver's function is to be the translator between the electrical signals of the hardware subsystems and the high-level programming languages of the operating system and application programs. Drivers take data that the operating system has defined as a file and translate them into streams of bits placed in specific locations on storage devices, or a series of laser pulses in a printer.

A driver helps the operating system communicate with the electrical signals from computer hardware.

Because there are such wide differences in the hardware, there are differences in the way that the driver programs function. Most run when the device is required, and function much the same as any other process. The operating system will frequently assign high-priority blocks to drivers so that the hardware resource can be released and readied for further use as quickly as possible.

One reason that drivers are separate from the operating system is so that new functions can be added to the driver -- and thus to the hardware subsystems -- without requiring the operating system itself to be modified, recompiled and redistributed. Through the development of new hardware device drivers, development often performed or paid for by the manufacturer of the subsystems rather than the publisher of the operating system, input/output capabilities of the overall system can be greatly enhanced.

Managing input and output is largely a matter of managing queues and buffers, special storage facilities that take a stream of bits from a device, perhaps a keyboard or a serial port, hold those bits, and release them to the CPU at a rate with which the CPU can cope. This function is especially important when a number of processes are running and taking up processor time. The operating system will instruct a buffer to continue taking input from the device, but to stop sending data to the CPU while the process using the input is suspended. Then, when the process requiring input is made active once again, the operating system will command the buffer to send data. This process allows a keyboard or a modem to deal with external users or computers at a high speed even though there are times when the CPU can't use input from those sources.

Managing all the resources of the computer system is a large part of the operating system's function and, in the case of real-time operating systems, may be virtually all the functionality required. For other operating systems, though, providing a relatively simple, consistent way for applications and humans to use the power of the hardware is a crucial part of their reason for existing.

Why Clean Your Computer?

Germs, Dead Skin Cells, Dust, and Maybe Even Buggers? What types of contaminates are in your computer? According to some experts, a toilet may be cleaner than your computer. That's right a toilet! In this article I will attempt to explain why you should clean or have your computer cleaned on a regular basis. Not only from a sanitary standpoint but also from a performance standpoint. US health expert Chuck Gerba a microbiologist from the University of Arizona performed a study on computer cleanliness and found that the average workstation has 400 times more bacteria than the average toilet. I don't know about you but: . . . . . . Yuck! According to computer giant IBM, if all the dust, dirt and contaminates were removed from with inside the computers, less than 1% would fail over the next few months. How often should you clean your computer? How often should a PC be cleaned? It really depends on the environment it is subjected to. If you are non-smoker we recommend cleaning or having your PC cleaned at least every six months. On the other hand if you are a smoker you should clean or have your computer cleaned every three months or so. Why clean your computer? Cleaning your computers and accessories on a regular basis can help stop the spread of germs and viruses as well as keep your PC and it's components in great working condition. Stop and think for a minute about all the things your computer may be subjected to everyday. Sanitary Reasons To Clean Dust, germs and viruses, dead skin cells, animal hair, human hair, food particles, cigarette smoke, salvia, and yes maybe even buggers. Can you think of more? These alone should make you want to scrub your keyboard, mouse, scanner, and computer right now and give it a thorough cleaning. Do the phones too, they are the worst! Performance Reasons To Clean When your computer and components are in operation static electricity is produced thus attracting dust particles to your PC. The two biggest enemies of computers and PC components are heat and corrosion. When dust builds up in your computer it forms a blanket on your inner components thus creating extra heat, not to mention components can now possibly short themselves across the many different circuits on the inside of your PC. Dust bunnies can form around your cooling fan and power supply restricting overall ventilation resulting in heat failure. We perform preventative maintenance on just about everything else we own, why do we overlook proper PC maintenance? You wouldn't let your car go for months and months without an oil change would you? I would recommend hiring a professional computer cleaning service for all of your computer cleaning needs. They are professionals and have all of the necessary tools and proper equipment to perform the needed operations. Most are very affordable - It's just worth letting a pro do the job.

Processor Management

The heart of managing the processor comes down to two related issues:

Ensuring that each process and application receives enough of the processor's time to function properly

Using as many processor cycles as possible for real work

The basic unit of software that the operating system deals with in scheduling the work done by the processor is either a process or a thread, depending on the operating system.

It's tempting to think of a process as an application, but that gives an incomplete picture of how processes relate to the operating system and hardware. The application you see (word processor, spreadsheet or game) is, indeed, a process, but that application may cause several other processes to begin, for tasks like communications with other devices or other computers. There are also numerous processes that run without giving you direct evidence that they ever exist. For example, Windows XP and UNIX can have dozens of background processes running to handle the network, memory management, disk management, virus checks and so on.

A process, then, is software that performs some action and can be controlled -- by a user, by other applications or by the operating system.

It is processes, rather than applications, that the operating system controls and schedules for execution by the CPU. In a single-tasking system, the schedule is straightforward. The operating system allows the application to begin running, suspending the execution only long enough to deal with interrupts and user input.

Interrupts are special signals sent by hardware or software to the CPU. It's as if some part of the computer suddenly raised its hand to ask for the CPU's attention in a lively meeting. Sometimes the operating system will schedule the priority of processes so that interrupts are masked -- that is, the operating system will ignore the interrupts from some sources so that a particular job can be finished as quickly as possible. There are some interrupts (such as those from error conditions or problems with memory) that are so important that they can't be ignored. These non-maskable interrupts (NMIs) must be dealt with immediately, regardless of the other tasks at hand.

While interrupts add some complication to the execution of processes in a single-tasking system, the job of the operating system becomes much more complicated in a multi-tasking system. Now, the operating system must arrange the execution of applications so that you believe that there are several things happening at once. This is complicated because the CPU can only do one thing at a time. Today's multi-core processors and multi-processor machines can handle more work, but each processor core is still capable of managing one task at a time.

In order to give the appearance of lots of things happening at the same time, the operating system has to switch between different processes thousands of times a second. Here's how it happens:

A process occupies a certain amount of RAM. It also makes use of registers, stacks and queues within the CPU and operating-system memory space.

When two processes are multi-tasking, the operating system allots a certain number of CPU execution cycles to one program.

After that number of cycles, the operating system makes copies of all the registers, stacks and queues used by the processes, and notes the point at which the process paused in its execution.

It then loads all the registers, stacks and queues used by the second process and allows it a certain number of CPU cycles.

When those are complete, it makes copies of all the registers, stacks and queues used by the second program, and loads the first program.

Low Disk Space Warning

Low Disk Space Warning: Ignore, Disable, or Obey?

One of the most annoying aspects of Windows is those warning messages that seem to pop up at the most inconvenient times. Although they are designed to warn you when potentially dangerous circumstances arise, some of these warnings are benign and can be closed without taking any actions. And there's the problem... as a result of so many warning messages, and due to a general fear of ANYTHING that pops up on the screen, some users tend to ignore ALL of them. And that can be bad. Sometimes.

One specific warning that computer users will see on a fairly regular basis as their hard drive fills up is the Low Disk Space warning: "You are running out of disk space on Local Disk [drive]. To free space on this drive by deleting old or unnecessary files, click here." So is this one important? Can you ignore it, disable it, or will doing so put your computer at risk?

What is the "Low Disk Space Warning"?

Windows created the low disk space warning to alert computer users when their hard drive is running low on available disk space. The first warning appears when a drive has less than 200 MB of available disk space, the second warning appears when the drive has less than 80 MB of available disk space and the most urgent warning appears when the drive has less than 50 MB of available disk space. As your disk space decreases, the frequency that the low disk space warnings pop-up on your screen increases, and it is because of this that many people decide to disable this warning in their Windows system settings.

Should you ignore these warnings and plow ahead? Here's the test: If you are running out of space on the system drive (almost always the C: drive), then you need to take action right away, or your system performance will begin to suffer, and your ability to recover from problems related to spyware and viruses will be negatively affected. You might even experience a computer lockup or crash (and potential loss of data) if you take no action.

If the warning refers to some other disk drive, such as the D: or E: drive, then probably you can safely ignore this warning. You still might want to explore those drives to clean up unwanted files or programs, but it won't cause any serious problems, expect perhaps that you'll run out of space to store new files on that drive. If you have a secondary hard drive with less than 200MB of storage, and you understand that's not a problem, then you CAN ignore or even disable this Low Disk Space warning. See below for some tips on how to do that.

As I mentioned earlier, if you have multiple drives, and the problem is not the system (C:) drive, the low space warning is not so important. You can disable the Low Disk Space warning by changing a setting in your system registry. The easiest and safest way to do so is with the tool. After downloading and starting TweakUI, click on Taskbar

and Start Menu, then UNCHECK the box next to "Warn when low on disk space". Click OK to exit from TweakUI, then restart your system to activate the new setting.

If you are comfortable mucking around in the Windows Registry

, then you can make this change without TweakUI. Start the REGEDIT program, then follow these steps:

Navigate down to HKEY_CURRENT_USER / Software / Microsoft / Windows / CurrentVersion / Policies / Explorer
If the NoLowDiskSpaceChecks key is not there, right-click to create a new DWORD value with that name.
Double-click on NoLowDiskSpaceChecks, enter 1 for the value
Press OK and exit from REGEDIT

Just remember, it's NOT a good idea to turn off the Low Disk Space warning when the problem is on the system drive. Bad Things will happen. Do you have comments or questions about the Low Disk Space warning message? Post your thoughts below...

Memory Storage and Management

When an operating system manages the computer's memory, there are two broad tasks to be accomplished:

1. Each process must have enough memory in which to execute, and it can neither run into the memory space of another process nor be run into by another process.

2. The different types of memory in the system must be used properly so that each process can run most effectively.

The first task requires the operating system to set up memory boundaries for types of software and for individual applications.

As an example, let's look at an imaginary small system with 1 megabyte (1,000 kilobytes) of RAM. During the boot process, the operating system of our imaginary computer is designed to go to the top of available memory and then "back up" far enough to meet the needs of the operating system itself. Let's say that the operating system needs 300 kilobytes to run. Now, the operating system goes to the bottom of the pool of RAM and starts building up with the various driver software required to control the hardware subsystems of the computer. In our imaginary computer, the drivers take up 200 kilobytes. So after getting the operating system completely loaded, there are 500 kilobytes remaining for application processes.

When applications begin to be loaded into memory, they are loaded in block sizes determined by the operating system. If the block size is 2 kilobytes, then every process that's loaded will be given a chunk of memory that's a multiple of 2 kilobytes in size. Applications will be loaded in these fixed block sizes, with the blocks starting and ending on boundaries established by words of 4 or 8 bytes. These blocks and boundaries help to ensure that applications won't be loaded on top of one another's space by a poorly calculated bit or two. With that ensured, the larger question is what to do when the 500-kilobyte application space is filled.

In most computers, it's possible to add memory beyond the original capacity. For example, you might expand RAM from 1 to 2 gigabytes. This works fine, but can be relatively expensive. It also ignores a fundamental fact of computing -- most of the information that an application stores in memory is not being used at any given moment. A processor can only access memory one location at a time, so the vast majority of RAM is unused at any moment. Since disk space is cheap compared to RAM, then moving information in RAM to hard disk can greatly expand RAM space at no cost. This technique is called virtual memory management.

Disk storage is only one of the memory types that must be managed by the operating system, and it's also the slowest. Ranked in order of speed, the types of memory in a computer system are:

High-speed cache -- This is fast, relatively small amounts of memory that are available to the CPU through the fastest connections. Cache controllers predict which pieces of data the CPU will need next and pull it from main memory into high-speed cache to speed up system performance.

Main memory -- This is the RAM that you see measured in megabytes when you buy a computer.

Secondary memory -- This is most often some sort of rotating magnetic storage that keeps applications and data available to be used, and serves as virtual RAM under the control of the operating system.

The operating system must balance the needs of the various processes with the availability of the different types of memory, moving data in blocks (called pages) between available memory as the schedule of processes dictates.

What is Virtual Memory

Virtual memory is non-physical memory.

Windows uses virtual memory when it doesn't have enough "regular"
physical memory to preform a task. When it does this, Windows uses your hard drive to store information that normally would be put into your RAM memory. Here's an overly simplified example:

Let's say you have 32 meg of RAM available. Now, you load a program that takes up 20 meg, and another that takes up 22 meg. You need a total of
42 meg, but you only have 32 meg of actual RAM memory. However, both programs still run. What's happening?

Windows is using 10 meg of hard drive space to supplement your physical
32 meg of RAM (don't worry, this 10 meg will be erased once Windows is done with it).

I know what you're thinking. Why bother to add extra RAM to my computer if it can use hard drive space instead? Main reason - RAM is much faster.

Whenever you're using a lot of virtual memory, you're slowing your computer down (way the heck down). The best work around is to get more physical memory. I recommend 64 - 128 meg, depending on how many programs you run simultaneously.

Oh, one more thing. If you don't have a lot of hard drive space left (I recommend a minimum of 100 meg) and you're experiencing lots of problems, lack of virtual memory may be why. When Windows runs out of memory (virtual and non-virtual), it just doesn't run all that well.

AJP - 2200C Review

This notebook, which uses a 1GHz Intel Pentium III processor and 128MB of RAM, features rather too much plastic for its own good, but it is well made and thoughtfully specified, with a price that should appeal to corporate IT buyers.

In fact, several of this notebook's components are more suited to the larger office environment, such as the standard spec of 128MB of RAM, the 10GB hard drive and the CD-RW drive. This latter is built in rather than modular, as is the floppy drive, and even the Lithium Ion battery pack can only be removed by the use of a screwdriver.

Continuing the corporate theme, the 2200C has a built-in 10/100Mbps NIC, with just a single Type II PC Card slot for plug-in modules. You do get a range of ports - including USB but not serial - but these are tucked out of the way on the back panel, to minimise desktop clutter.

Ergonomically this is quite a comfortable machine, with a good keyboard layout and accessible mouse trackpad, although there are no feet so the actual angle of the keyboard can't be changed. The 14.1-inch SVGA TFT screen is reasonable and gives plenty of workspace, but with rather more brightness variation across the screen than we'd have liked.

Plastic, rather than alloy, has been used for most of the case construction of this notebook, and that means the screen backing is prone to flexing under pressure. Despite this, the construction quality seems good enough to survive a few knocks and bumps, as long as it isn't treated too roughly.

There's a Kensington lock slot and software/BIOS security to help deter intruders, and a one year RTB warranty is provided as standard, which may not be enough for companies looking to keep potential downtime to a minimum. On-site repairs would generally be preferable, but that's probably our biggest complaint about this machine, which otherwise appears to be a dependable workhorse.

AJP - 2200C features - Verdict

A sensible if unexciting notebook, the AJP 2200C could be a good bulk-buy for corporates looking for ultra-fast, semi-portable machines for their workforce. It's uninspiring, but it does the job.

AJP - 2200C price

1,300 + VAT

AJP Computers: 020 8208 9733

Bitdefender Anti Virus Antivirus 2008 Review

BitDefender Antivirus 2008 is perhaps the most improved of the antivirus applications we've seen so far this year. It is fast and light, and like Kaspersky Anti-Virus 7, our current Editor's Choice winner, BitDefender Antivirus 2008 offers hourly updates. However, we'd like more access to configuration options beyond simple enabling and disabling features. Still, for the price, and for the excellent quality of its antivirus protection, BitDefender Antivirus 2008 ranks among our few top contenders for 2008. For a look inside see our BitDefender Antivirus 2008 slideshow.

Setup
We experienced no problems during several installations during the end of August 2007. Installation requires a reboot.

Should you want to uninstall BitDefender Antivirus 2008, the All Programs menu includes an uninstall option. After reboot we could find no traces of BitDefender Antivirus 2008 left on our test system.

Interface
BitDefender Antivirus 2008 opts for a no-nonsense interface. Should there be any security issues, one of the large icons will display red. For remediation there's a large Fix This button, or you can click the specific graphic to see what's wrong. We experienced only minor issues with this approach.

BitDefender Antivirus 2008 offers a no-nonsense interface.

Upon installation, our Identity Privacy icon displayed red. Clicking either the Fix This Issue button or the Identity Privacy icon took us to a rule creation page. Now what? To get the Identity Privacy icon to go green, we either had to create a rule or turn off the feature, yet we were not given enough information to make that choice. Keeping Identity Privacy enabled assumes that you are comfortable providing personal details such as passwords and credit card information. Rather than fill out real information, we created a faux Social Security number of 123-45-6789 to satisfy BitDefender's request without disabling the feature. For the moment, the icon is green, but we're on the fence whether to keep the Identity Privacy feature enabled or disable it completely.

Features
BitDefender Antivirus 2008 covers a lot of ground, protecting your system from viruses, spyware, privacy breaches, phishing attacks, and rootkits. And BitDefender is the only antivirus product we've seen that advertises a Gamer mode, minimizing protection alerts and resources while you're off playing games.

For out-of-the-box protection, for the most part, we agree with BitDefender's default settings. For instance, with antivirus scans, the default setting scans files during boot, recently accessed files, packed files (although not archived files), incoming and outgoing e-mails--so far so good. The only difference with the more aggressive setting available is the addition of scanning activity on port 80 and port 443. BitDefender's HTTP scan blocks malicious ActiveX and JavaScript, and is part of the antivirus and antispyware protection. Do you need that? Again, there is not enough guidance within the program to help users make that decision; most browsers offer add-ons that will also screen for these scripts.

As for the default privacy protection, BitDefender will look for instances of private information leaving the computer and guard against spyware attempting to install on the machine. The more aggressive setting adds cookie control and script protection, which most browsers will also allow you to control. Do you need this protection if your browser already provides similar protection? Again, BitDefender doesn't offer enough guidance within the program to help users make that decision. Most browsers offer free add-ons that will screen for these scripts as well.

Performance
BitDefender Antivirus 2008 scored well in both our CNET Labs' performance tests and in one third-party, independent antivirus test using live viruses. On our iTunes test, BitDefender Antivirus 2008 was tied for first, completing in a fast 270 seconds, just 2 seconds above our test system. On our Microsoft Office test, BitDefender Antivirus 2008 came in near the middle at 1,426 seconds. For scanning a single folder with files, BitDefender Antivirus 2008 came in second requiring 163 seconds. And in boot speed, BitDefender Antivirus 2008 came in first, with a respectable 28 seconds. To find out how we test, see CNET Labs' How we test: software: antivirus page.

In terms of protecting your PC, we cite results from two leading independent antivirus testing organizations. In the latest test results from AV-Comparatives.org, for on-demand scans, the previous version, BitDefender Professional 10+, earned an Advanced (second-highest) rating, catching 96 percent of all malware tested; and for the Retrospective/Proactive test, BitDefender Professional 10+ also earned a Standard (middle) rating, detecting almost half the backdoors, Trojans, and other malware sampled. BitDefender was not tested by CheckVir.com, our second choice for test results.

Support
BitDefender provides a fairly complete package of technical support for its antivirus product. Greatly improved from last year is the built-in help file, although it would be nice if it were also context sensitive so that when we have a question about the Identity Pirvacy feature, the help file opens on that section immediately. BitDefender also offers an online Getting Started document, but we found its intended audience to be the Internet security suite users, not those starting out with just the antivirus product. BitDefender also delivers an adequate online FAQ, and there are several active user forums. Finally, you can e-mail or call a toll-free number, 888-868-1873, for live technical support.

Conclusion
While we like many features of BitDefender Antivirus 2008 and recognize that it has greatly improved since last year, we were disappointed by the overall feeling we get when using the application. In particular, the configuration settings could be more nuanced beyond just enable and disable. And the settings that are available could be better explained. Often we were left changing settings without being given enough context to make the right decisions.

The good: BitDefender Antivirus 2008 protects against viruses, spyware, phishing attacks, and rootkits, and performs well on third-party, independent antivirus tests.

The bad: The application configuration options are often either "enable" or "disable"--we'd like more options.

The bottom line: BitDefender Antivirus 2008 has greatly improved since last year; we'd like more access to configuration options beyond simple enabling and disabling features.

Click Here to View Great Prices on Antivirus Software

Elonex - Piranha Review

Sub-notebooks are where computing is most sexy, and the Piranha is one of the more desirable examples we've seen. Its design is effectively that of a miniature notebook, with a smaller screen and external CDROM and floppy, as opposed to the esoteric designs favoured by Sony or Toshiba whose compacted keyboards and half-sized screens can make for usability problems.

The case pretends to be metallic, with a silver and black colour scheme, but is actually plastic. However, this proves not to be an issue because the rigid lid protects the screen well. While there's minor play in some of the hinges of the hatches that allow access to the hard disk, for example, the Piranha largely feels rugged and tough enough for life on the road. At a little under 3kg when weighed on our scales (complete with drives and power supply), it's also light enough to make transportation easy.

The keyboard retains full-sized dimensions (just about) making for fast touch-typing once you've got used to the reduced travel of the keys. And although the 12-inch TFT screen limits you to a mere 800x600 resolution (compared to the 1024x768 that most people prefer on their desktop monitors), at least a nice bright TFT panel is used, which allows full adjustment of brightness and contrast to suit varying environmental conditions. Only 2Mb of display memory is used, though, which limits the resolutions and colour depths you can get if you plug the machine into an external monitor.

Inside the case it's a rosy picture. There was a time when the components of sub-notebooks would lag behind full-sized notebooks, but this simply isn't the case any longer. With a mobile Pentium II 400 and 64MB of RAM, the Piranha has a great turn of speed. It's certainly enough to keep those office applications turning over quite nicely, thank you very much, although don't expect miracles; it still won't manage many of the latest 3D shoot-em-ups.

Even the hard drive manages to defy the logic that if you have a smaller notebook then you have to make do with lesser components. At 6.4Gb, it's large enough to avoid upgrade worries for at least a couple of years.

The touchpad at the front of the machine is large enough and responsive enough to be very useful, although perhaps a little over sensitive - we noticed that it often registered a tap when we were taking our fingers away, causing text to be accidentally highlighted in Word, for example.

The floppy and CDROM drives are supplied as external devices which attach to the side of the machine via a proprietary port. While the floppy can be 'hot swapped' (ie. plugged in and unplugged while the machine is up and running), the CDROM drive is only recognised if the Piranha is booted-up with it attached. This is a minor but irritating point. Expansion elsewhere is standard - a single Type II PC Card slot, a single USB port and the usual collection of parallel, serial, VGA and keyboard sockets.

Battery life was also promising and we consistently managed around two and a half hours or so between recharges. Once again, this compares favourably to many full-sized notebooks and certainly defies the idea that sub-notebooks drain the juice quickly.

Elonex - Piranha features - Verdict

At 1,399 before you add VAT, the Piranha is not cheap. Without a doubt you are paying a premium for the smaller dimensions it brings with it. But it is good at what it's designed for and fairly hard to criticise. The cutting-edge specification also means that it will retain its usefulness for a good few years.

Elonex - Piranha price

1,399 + VAT

Elonex: 020 8452 2444

www.elonex.co.uk

How Hard Disks Work

Nearly every desktop computer and server in use today contains one or more hard-disk drives. Every mainframe and supercomputer is normally connected to hundreds of them. You can even find VCR-type devices and camcorders that use hard disks instead of tape. These billions of hard disks do one thing well -- they store changing digital information in a relatively permanent form. They give computers the ability to remember things when the power goes out.

In this article, we'll take apart a hard disk so that you can see what's inside, and also discuss how they organize the gigabytes of information.

Hard Disk Basics

Hard disks were invented in the 1950s. They started as large disks up to 20 inches in diameter holding just a few megabytes. They were originally called "fixed disks" or "Winchesters" (a code name used for a popular IBM product). They later became known as "hard disks" to distinguish them from "floppy disks." Hard disks have a hard platter that holds the magnetic medium, as opposed to the flexible plastic film found in tapes and floppies.

At the simplest level, a hard disk is not that different from a cassette tape. Both hard disks and cassette tapes use the same magnetic recording techniques described in How Tape Recorders Work. Hard disks and cassette tapes also share the major benefits of magnetic storage -- the magnetic medium can be easily erased and rewritten, and it will "remember" the magnetic flux patterns stored onto the medium for many years.

Cassette Tape vs. Hard Disk

Let's look at the big differences between cassette tapes and hard disks:

The magnetic recording material on a cassette tape is coated onto a thin plastic strip. In a hard disk, the magnetic recording material is layered onto a high-precision aluminum or glass disk. The hard-disk platter is then polished to mirror-type smoothness.

With a tape, you have to fast-forward or reverse to get to any particular point on the tape. This can take several minutes with a long tape. On a hard disk, you can move to any point on the surface of the disk almost instantly.

In a cassette-tape deck, the read/write head touches the tape directly. In a hard disk, the read/write head "flies" over the disk, never actually touching it.

The tape in a cassette-tape deck moves over the head at about 2 inches (about 5.08 cm) per second. A hard-disk platter can spin underneath its head at speeds up to 3,000 inches per second (about 170 mph or 272 kph)!

The information on a hard disk is stored in extremely small magnetic domains compared to a cassette tape's. The size of these domains is made possible by the precision of the platter and the speed of the medium.

Because of these differences, a modern hard disk is able to store an amazing amount of information in a small space. A hard disk can also access any of its information in a fraction of a second.

How To Share A Printer

Sharing a printer between multiple computers on a home network is quite easy to do. Sharing a printer saves the cost of having to purchase an additional printer or a separate printer server box, and at the same time it makes it much more convenient for more than one person to get work done without the mess of transferring documents from computer to computer. The downside to printer sharing via Windows is that the master computer must be turned on any time the other computers want to print thereby wasting energy.

Preparing the Printer To Be Shared

In order to share a printer on a local area network (LAN) the computer controlling the printer as well as any other computers that wish to use the shared printer must first be networked together. Most home based LANs use a small router that connects to the homes Internet connection (cable internet, DSL, or dial up).

Each individual computer then plugs into this router either wirelessly using Wi-Fi technology or through standard Ethernet cables. Each of the additional computers must also have a copy of the printer's device driver software installed on them (even though they are not directly connected to the printer). Once each machine has the device drivers installed and all are connected to the network a user can proceed to the next step of activating printer sharing in Windows.

Activating Windows Printer Sharing

On a Windows machine, go to Start>Control Panel> Printers and Faxes. The list that pops up contains all of the printers and fax machines that are currently connected to the computer. Select the printer that is to be shared and then click "Share This Printer" from the Printer Tasks column. Using the window that opens up, click "Share This Printer," and give it a name.

Connecting To The Shared Printer

On each of the other networked computers proceed in much the same way. Go to Start>Printers and Faxes but click on Add A Printer. Select Connect to a Networked Printer. Click on Browse for a Printer and select the name of the computer (and printer) that was shared in the previous step. If for some reason the computer and printer cannot be found go back to the master computer and make sure that the Windows firewall is set to allow printer sharing.

Rock - Sigma Review

Sony proved last year with its Vaio range of laptops that notebook PCs don't have to look like dark grey paving slabs, and many other vendors have since followed suit with sexy laptops of their own. Rock has recently entered the fray with this new Sigma, which combines a good selection of features with a stylish and eminently usable design.

The Sigma is powered by a 400MHz Celeron processor, and uses the Intel 430BX chipset. This entry-level model is equipped with 32MB of memory and a 4.3GB EIDE hard drive, while other options include 96MB of memory and a 6GB drive. Opening the case reveals a 14.1-inch XGA screen (with a native resolution of 1024 x 768) which is driven by an ATI Rage LT Pro graphics chip. This graphics controller is equipped with 8MB of video memory, which is more than sufficient to drive the bright, clear screen at its top resolution in 16.7 million colours (24-bit). Some 3D acceleration features are present too, although this is not really a games machine.

Located underneath the screen is a comfortable keyboard, most of whose keys are full-sized. There's a trackpad pointing device with mouse buttons set into the generous wrist-rest, while a pair of speakers at the front of the case is powered by a Crystal FM sound chip. In addition to the two Type II PC Card (PCMCIA) slots, there's the usual array of ports built into the Sigma's case, with the addition of an integrated WinModem.

Rock - Sigma features - Verdict

Although quite big and heavy, the Sigma justifies its size by having both floppy and CD drives built in. Its stylish casing conceals these components - along with other useful gadgets such as the modem - very tidily, and the Sigma looks and feels considerably more durable than many notebook PCs on the market. If you're looking for something different to the usual clone laptops, but still want to pay for the equipment rather than the name, then the Sigma is worth consideration.

Rock - Sigma price

1,099 + VAT

Rock: 01926 816609

Graph Data Structures - Disjoint-Sets

Disjoint-set data structure

Given a set of elements, it is often useful to break them up or partition them into a number of separate, nonoverlapping sets. A disjoint-set data structure is a data structure that keeps track of such a partitioning. A union-find algorithm is an algorithm that performs two useful operations on such a data structure:

Find: Determine which set a particular element is in. Also useful for determining if two elements are in the same set.
Union: Combine or merge two sets into a single set.

Because it supports these two operations, a disjoint-set data structure is sometimes called a merge-find set. The other important operation, MakeSet, which makes a set containing only a given element (a singleton), is generally trivial. With these three operations, many practical partitioning problems can be solved (see the Applications section).

In order to define these operations more precisely, we need some way of representing the sets. One common approach is to select a fixed element of each set, called its representative, to represent the set as a whole. Then, Find(x) returns the representative of the set that x belongs to, and Union takes two set representatives as its arguments.

Disjoint-set linked lists

Perhaps the simplest approach to creating a disjoint-set data structure is to create a linked list for each set. We choose the element at the head of the list as the representative.

MakeSet is obvious, creating a list of one element. Union simply appends the two lists, a constant-time operation. Unfortunately, with this implementation Find requires Ω(n) or linear time with this approach.

We can avoid this by including in each linked list node a pointer to the head of the list; then Find takes constant time. However, we've now ruined the time of Union, which has to go through the elements of the list being appended to make them point to the head of the new combined list, requiring Ω(n) time.

We can ameliorate this by always appending the smaller list to the longer, called the weighted union heuristic. This also requires keeping track of the length of each list as we perform operations to be efficient. Using this, a sequence of m MakeSet, Union, and Find operations on n elements requires O(m + nlog n) time. To make any further progress, we need to start over with a different data structure.

Disjoint-set forests

We now turn to disjoint-set forests, a data structure where each set is represented by a tree data structure where each node holds a reference to its parent node. Disjoint-set forests were first described by Bernard A. Galler and Michael J. Fisher in 1964, although their precise analysis took years.

In a disjoint-set forest, the representative of each set is the root of that set's tree. Find simply follows parent nodes until it reaches the root. Union combines two trees into one by attaching the root of one to the root of the other. One way of implementing these might be:

 function MakeSet(x)

     x.parent := null

 function Find(x)

     if x.parent == null

        return x

     return Find(x.parent)

 function Union(x, y)

     xRoot := Find(x)

     yRoot := Find(y)

     xRoot.parent := yRoot

In this naive form, this approach is no better than the linked-list approach, because the tree it creates can be highly unbalanced, but it can be enhanced in two ways.

The first way, called union by rank, is to always attach the smaller tree to the root of the larger tree, rather than vice versa. To evaluate which tree is larger, we use a simple heuristic called rank: one-element trees have a rank of zero, and whenever two trees of the same rank are unioned together, the result has one greater rank. Just applying this technique alone yields an amortized running-time of $O (log n)$ per MakeSet, Union, or Find operation. Here are the improved MakeSet and Union:

 function MakeSet(x)

     x.parent := null

     x.rank   := 0

 function Union(x, y)

     xRoot = Find(x)

     yRoot = Find(y)

     if xRoot.rank > yRoot.rank

         yRoot.parent := xRoot

     else if xRoot.rank < yRoot.rank

         xRoot.parent := yRoot

     else if xRoot != yRoot

         yRoot.parent := xRoot

         xRoot.rank := xRoot.rank + 1

The second improvement, called path compression, is a way of flattening the structure of the tree whenever we use Find on it. The idea is that each node we visit on our way to a root node may as well be attached directly to the root node; they all share the same representative. To effect this, we make one traversal up to the root node, to find out what it is, and then make another traversal, making this root node the immediate parent of all nodes along the path. The resulting tree is much flatter, speeding up future operations not only on these elements but on those referencing them, directly or indirectly. Here is the improved Find:

 function Find(x)

     if x.parent == null

        return x

     x.parent = Find(x.parent)

     return x.parent

These two techniques complement each other; applied together, the amortized time per operation is only $O (α(n))$ , where $α(n)$ is the inverse of the function $f (n) = A (n, n)$ , and $A$ is the extremely quickly-growing Ackermann function. Since $α(n)$ is its inverse, it's less than 5 for all remotely practical values of $n$ . Thus, the amortized running time per operation is effectively a small constant.

In fact, we can't get better than this: Fredman and Saks showed in 1989 that $Ω(α(n))$ words must be accessed by any disjoint-set data structure per operation on average.

Applications

Disjoint-set data structures arise naturally in many applications, particularly where some kind of partitioning or equivalence relation is involved, and this section discusses some of them.

Tracking the connected components of an undirected graph

Suppose we have an undirected graph and we want to efficiently make queries regarding the connected components of that graph, such as:

Are two vertices of the graph in the same connected component?
List all vertices of the graph in a particular component.
How many connected components are there?

If the graph is static (not changing), we can simply use breadth-first search to associate a component with each vertex. However, if we want to keep track of these components while adding additional vertices and edges to the graph, a disjoint-set data structure is much more efficient.

We assume the graph is empty initially. Each time we add a vertex, we use MakeSet to make a set containing only that vertex. Each time we add an edge, we use Union to union the sets of the two vertices incident to that edge. Now, each set will contain the vertices of a single connected component, and we can use Find to determine which connected component a particular vertex is in, or whether two vertices are in the same connected component.

This technique is used by the Boost Graph Library to implement its Incremental Connected Components functionality.

Note that this scheme doesn't allow deletion of edges even without path compression or the rank heuristic, this is not as easy, although more complex schemes have been designed that can deal with this type of incremental update.

Computing shorelines of a terrain

When computing the contours of a 3D surface, one of the first steps is to compute the "shorelines," which surround local minima or "lake bottoms." We imagine we are sweeping a plane, which we refer to as the "water level," from below the surface upwards. We will form a series of contour lines as we move upwards, categorized by which local minima they contain. In the end, we will have a single contour containing all local minima.

Whenever the water level rises just above a new local minimum, it creates a small "lake," a new contour line that surrounds the local minimum; this is done with the MakeSet operation.

As the water level continues to rise, it may touch a saddle point, or "pass." When we reach such a pass, we follow the steepest downhill route from it on each side until we arrive a local minimum. We use Find to determine which contours surround these two local minima, then use Union to combine them. Eventually, all contours will be combined into one, and we are done.

Classifying a set of atoms into molecules or fragments

In computational chemistry, collisions involving the fragmentation of large molecules can be simulated using molecular dynamics. The result is a list of atoms and their positions. In the analysis, the union-find algorithm can be used to classify these atoms into fragments. Each atom is initially considered to be part of its own fragment. The Find step usually consists of testing the distance between pairs of atoms, though other criterion like the electronic charge between the atoms could be used. The Union merges two fragments together. In the end, the sizes and characteristics of each fragment can be analyzed.

History

While the ideas used in disjoint-set forests have long been familiar, Robert Tarjan was the first to prove the upper bound (and a restricted version of the lower bound) in terms of the inverse Ackermann function. Until this time the best bound on the time per operation, proven by Hopcroft and Ullman, was O(log* n), the iterated logarithm of n, another slowly-growing function (but not quite as slow as the inverse Ackermann function). Tarjan and van Leeuwen also developed one-pass Find algorithms that are more efficient in practice. The algorithm was made well-known by the popular textbook

How to Install a Front Loading Drive - part 6

Optimising performance

To achieve top speeds for reading and writing with your CD-ReWriter drive, direct memory access (DMA) must be enabled for the drive. To enable DMA under Windows 95, 98, or Me:
1.	Click the Start button, then Settings, then Control Panel, then double-click on System icon, then click on Device Manager tab. You will see a list of devices in your system.
2.	Double-click the CD-ROM icon, select the CD-ReWriter drive by clicking on it once. Click on the Properties button and select the Settings tab. You'll see the drive properties for the CD-ReWriter drive:
3.	Ensure the DMA box is checked.
4.	Click on OK button and then click the Close button to exit the System Properties window.
5.	When prompted if you want to restart your computer now, select Yes for this change to be enabled and saved.

To enable DMA under Windows 2000 or XP:
1.	Right-click My Computer and select Properties.
2.	Select the Hardware tab and then Device Manager.
3.	Double-click IDE ATA/ATAPI Controllers to expand the options.
4.	Under IDE ATA/ATAPI Controllers, double-click on the listing to bring up the property dialog box for the Primary IDE channel.
5.	Click on the Advanced Settings tab.
6.	If available, set Transfer Mode for Device 0 and 1 to DMA if available. Then select OK.
7.	You're asked if you would like to reboot at this point. Select NO.
8.	Repeat steps 4 6 for the Secondary IDE channel.
9.	This time, when you are prompted, select Reboot.
Buffer underrun is one of the biggest problems encountered in CD recording. This can happen when attempting to burn a CD whilst performing other tasks, or when recording from a "slow" source to a "fast" target. Once the burning process starts, it is essential that the data to be recorded is available for writing to the CD all the way to the end. Buffer underrun occurs when the computer system fails to sustain the datastream to the CD-writer for the duration of the recording process. The result is that the recording fails and the media becomes unusable and unrecoverable. To reduce the possibility of buffer underrun, all modern CD-writers have a built-in data buffer which stores the incoming data so that the CD-writer is one step removed from a potentially too slow data source. In the second half of 2000 CD-RW drives appeared using a drive level combination of hardware/firmware that made buffer underrun a thing of the past. Originated and patented by Sanyo, BURN-Proof technology (Buffer UndeRuN-Proof technology) works by constantly checking the status of the CD-writer's data buffer so that recording can be stopped at a specific location when an impending buffer-underrun condition is detected - typically when the buffer falls below a certain threshold of its maximum capacity - and resumed when the buffer has been sufficiently replenished after first repositioning the CD-writer's optical pickup to the appropriate sector. Plextor uses Sanyo's technology in combination with its own "PoweRec" (Plextor Optimised Writing Error Reduction Control) methodology. With this, the recording process is periodically paused using BURN-Proof technology, to allow the write quality to be checked so as to determine whether or not it is good enough to allow the recording speed to be incrementally increased. Other drive manufactures either licence similar technology or have developed their own variants. Mitsumi and LG Electronics both use OAK Technology's "ExacLink" system, Yamaha do likewise but under the brand name "SafeBurn". Acer Communications refer to their technology as "Seamless Link" and Ricoh to theirs as "JustLink".

Fujitsu - Lifebook L460 Review

Fujitsu's Lifebook range of products, first introduced a few years ago, has built up a good reputation for style and reliability. This is the latest model in the range, and although the reliability part of the equation has yet to be proved, the Lifebook L460 certainly has style in abundance. It's an ultra-slim machine with a 13.3-inch TFT screen, a full-sized keyboard and plenty of expansion options.

First, the style. Fujitsu has not been slow to respond to Sony's forays into the 'cute computing' arena. The Lifebook L460 is two-tone silver and black, about an inch wider than its screen and just over an inch deep with the lid closed. It weighs just under two kilos and is eminently portable. There's a large wrist-rest area beneath the keyboard - whose keys are light and comfortable - in which is housed a trackpad pointing device and two buttons.

As far as specification is concerned, the Lifebook L460 is powered by an Intel Pentium II processor running at 333MHz, and supported by Intel's 440BX chipset. There's a standard memory count of 32MB, which can be upgraded to a maximum of 160MB via a single upgrade slot, and a lithium-ion battery pack. The screen is quite clear and sharp, with a slider to control brightness, and is driven by a NeoMagic 128xd controller with 2MB of memory. Top resolution is 1024 x 768 with 256,000 colours (18-bit colour depth). Just below the screen are two speakers, powered by an Ensoniq sound chip, and there are audio ports and a volume control at the side.

Considering how thin this notebook is, Fujitsu has crammed in plenty of expansion options. There's a single Type II PC Card (PCMCIA) slot, while at the rear are serial, parallel, VGA, USB, Infra-red and keyboard/mouse ports. There's also a small connector for attaching the supplied floppy drive (which can be hot-plugged at any time), since the Lifebook L460 has no internal drives apart from its 4GB EIDE hard drive.

Optional gadgetry for the Lifebook L460 includes the Mobile Bay unit supplied with our review system. This can be plugged into the bottom of the notebook and can hold either a CDROM drive, or the floppy drive, or a second battery pack. Alternatively, those with more demanding requirements may prefer the Mobile Dock, which has CDROM and floppy drives plus port replication, a Fast Ethernet adapter, second battery holder and a Type III PC Card slot. Other options include DVD-ROM and SuperDisk (LS-120) drives, while the software supplied with the notebook includes anti-virus and cryptography tools.

Fujitsu - Lifebook L460 features - Verdict

Fujitsu's cunning knack of combining function with style continues with this Lifebook. The L460 is powerful enough for most users, has a pretty good screen and keyboard, is light and compact and yet can be easily converted into a desktop replacement system with DVD and Ethernet capabilities. You have to pay for good design, of course, but this is a stylish notebook with lasting value.

Fujitsu - Lifebook L460 price

2,095 + VAT (RRP) with Mobile Bay

Fujitsu: 01344 475000

Diamond - Rio PMP300 Review

The Rio was the first MP3 player on the market and in terms of styling shows its age. But in terms of features the Rio hasn't dated at all. There are four equalisation modes that beef up the sound - normal, classic, jazz and rock - although usually it's a matter of cycling through them to find which sounds best. There's also an intro play button, and an A-B function which repeats an excerpt of music. There are also random play and track repeat buttons.

Noticeably missing is a track name listing on the LCD panel. However, you do get a minute and second count and an indication of the remaining battery power.

The in-ear headphones proved both clear and punchy in our tests, avoiding the overly wet bass response of most personal stereo headphones. We'd argue they were possibly the best on test here although, as always, sound quality is subjective.

Inside the Rio is 32MB of memory and this can be expanded by a flash card slot on the underside of the machine. The card can be locked in place, and a separate control also allows you to lock the controls to avoid accidentally pressing them.

Power is from a single AA battery and connection to the PC is by the parallel port. The Rio Manager software looks fantastic and also lets you play music CDs, but perhaps isn't the easiest to use. We had to experiment a little to find out how to download songs into the player. With an ECP parallel port, songs took around 10 seconds to transfer, which we felt was plenty fast enough. Also supplied is Music Match Jukebox which lets you 'rip' songs from CD.

Diamond - Rio PMP300 price

84 + VAT

Diamond Multimedia: 01189 444400

How to Install a Front Loading Drive - part 4

Making the connections

As well as configuration jumper blocks, the back of the CD-ReWriter has a number of connectors.
Each of these will need to be connected to the appropriate location on the motherboard, or to a motherboard expansion card.
Power connector: Connect a large 4-pin white connector from the power supply to the drive's male 4-pin power connector.
Note, the computer s power cable connector and the drive s power receptacle are keyed. Inserting the power cable connector improperly will damage the drive.
IDE connector: The IDE cable connector is connected to an IDE cable. An IDE ribbon cable has three plugs - one for the motherboard and the other two for the connected drives. These days they're colour-coded; the blue connector goes into the motherboard, the black connector - furthermost away from the blue end - is for master drive and the grey connector - in the middle - is for the slave drive. Most cables are keyed, to prevent them being fit the wrong way round. In the absence of a key, the rule is that the red (or blue) line always goes next to pin 1. Since the advent of ATA/100, two types of cable have existed, one having twice the number of wires as the standard type. This 80-conductor cable puts a ground pin between each control and data signal, thereby improving signal reliability.


Take care to avoid plugging your IDE ribbon cable upside down into either your drive or motherboard. For correct orientation, match the red stripe along one side of an IDE ribbon cable to Pin 1 on the motherboard and Pin 1 - the pin closest to the power connector - on the drive. Each connector on the ribbon cable has a key in the middle. This key should fit into a slot in the middle of each connector of the motherboard and internal IDE peripherals.
The blue connector is connected to one of the two motherboard IDE connectors and either of the grey or black connectors connects to the internal IDE drive.
Before the CD-ReWriter is connected careful consideration is required, both as to which of the IDE channels to connect it to and how it should be configured - as master or slave - on the chosen channel.
Although a single IDE channel can handle two connected devices, it's important to understand that these share the channel, which can only process a single request at a time. This means that when one device is active, the other is, by definition, inactive. In the event of two requests being made simultaneously, an IDE controller will give precedence to that made by the primary device. Furthermore, the chipset on some older systems will not support independent timing, with the result that both devices connected to an IDE channel will run at the speed of the slowest. These factors need to be taken into account in determining which configuration of multiple IDE/ATA devices will maximise your overall system performance. The most common 4-drive scenario is: hard drive 1 hard drive 2 CD-ROM drive CD-(Re)Writer drive The first hard disk drive should always be configured as the primary master. In the past, the conventional wisdom was that the way to minimise making "coasters" was to have the CD-ROM and CD-Writers on different channels, and to configure the CD-ROM drive as a master. For older systems this may still be an important consideration. However, it's less relevant for more modern systems, and especially those that include a CD-Writer that supports one of the several technologies now available for avoiding buffer underruns. On the assumption that the hard drives are likely to be the fastest devices, perhaps a more appropriate rule is to allocate these as the primary devices on each of the IDE channels unless you have a dual-boot system, in which case they should be configured as master and slave on the primary channel. The bottom line is that there's no one single configuration that is optimal for everyone. You simply need to figure out what arrangement will work best for you, and perhaps refine this by trial and error. In truth, the more modern your system, the less likely is that the way in which you configure your IDE channels will make an appreciable difference to performance.

In this case the current IDE configuration is two hard disks connected as Master and Slave devices on primary IDE port, and a CD-ROM drive connected as Master device on the secondary IDE port. The manufacturer's favoured configuration was to have the CD-ReWriter as Master on the secondary IDE channel, with no drive connected to the other connector. Since this wasn't possible, an alternative recommendation - to re-connect the CD-ROM drive to the secondary IDE port as the Slave device and connect the CD-ReWriter as to the same IDE channel as Master - was followed.
Since the IDE cabling is easier if the Master drive on a particular IDE channel occupies a drive bay above the Slave drive. In this case the existing CR-ROM drive was relocated so as to allow this.
In fact, we're using rounded IDE cables here. These have been around for a few years and have found favour with the PC modding community because they look a lot better than conventional ribbon cables.
They won't improve the performance of your system, but they may well allow it to run cooler as a result of improved airflow around your system. They're much easier to install than regular ribbon cables, bending and twisting more freely and being easier to fasten down with cable ties.
Sadly, for some reason that must forever remain a mystery, it proved impossible to get the CD-ReWriter/Master, CD-ROM drive/Slave configuration to work!
Nothing - including updating the motherboard's chipset drivers - would get the CD-Writer to be recognised as secondary IDE channel Master.
Only by switching the drives' Master/Slave designations - and so physically switching the drives' bay positions too! - was it possible to get Windows 98 to recognise both drives properly.
Audio connector: If appropriate, you may connect the CD-ReWriter's analogue audio output connector to an audio amplifier or a sound card's internal audio input connector using a sound cable terminated with a standard MPC-3 type, 4-pin connector.
Often, retail optical drive products will include such a cable. The larger connector connects to the CD-ReWriter.
An alternative audio option - and one that will provide purer sound than the analogue audio connector - is to connect the CD-ReWriter's digital audio output connector to a sound card that supports Sony/Philips digital interface (SPDIF) or Digital-In, using an audio cable terminated at both ends with a 2-pin Molex connector.

In the absence of a sound card, a motherboard with integrated sound will provide at least an analogue audio connector, typically labelled as a CD-IN Connector.

CPU Technology - part 13

Intel Core 2

The announcement of the successor to the Intel Core Duo processor in the summer of 2006 also marked the reunification of Intel's desktop and mobile product lines. Low power consumption was a principal goal of the Intel Core microarchitecture, and the moblie CPU, previously codenamed "Merom", was listed as having a TDPs of 35 watts for the standard version and an impressive 5 watts TDP for Ultra Low Voltage (ULV) versions. Moreover, Intel claimed the chip was capable of 20% more performance at the same power level compared with the Core Duo.

The table below, which compares the mobile Core 2 Duo processor and its closest relation, the Core Duo predecessor, identifies several of the relatively minor improvements in the Core microarchitecture, which combine to achieve a significant hike in overall system performance:

	Core 2 Duo (Merom)	Core Duo (Yonah)
Manufacturing Process	65nm	65nm
Die Size	143mm²	90mm²
Transistors	291 million	151 million
Clock Speeds	1.06GHz - 2.4GHz+	1.20GHz - 2.33GHz
FSB Frequency	533MHz - 800MHz	533MHz - 667MHz
L1 Cache Size	32KB + 32KB	32KB + 32KB
L2 Cache Size	2MB - 4MB Shared	2MB Shared
Pipeline Stages	14	12
Decoders	1 complex + 3 simple	1 complex + 2 simple
Maximum Decode Rate	4+1	3
Reorder Buffer	96	80
SSE Units	3	1
Socket Interface	Socket-M (PGA/BGA) Socket-P (PGA/BGA)	Socket-M (PGA/BGA)

The mobile Core 2 Duo processors, in aprticular, include a number of advanced innovations, including:

Intel Dynamic Power Coordination: Coordinates Enhanced Intel SpeedStep Technology and idle power-management state (C-states) transitions independently per core to help save power.
Intel Dynamic Bus Parking: Enables platform power savings and improved battery life by allowing the chipset to power down with the processor in low-frequency mode.
Enhanced Intel Deeper Sleep with Dynamic Cache Sizing: Saves power by flushing cache data to system memory during periods of inactivity to lower CPU voltage.

Process Control Block

All of the information needed to keep track of a process when switching is kept in a data package called a process control block. The process control block typically contains:

An ID number that identifies the process

Pointers to the locations in the program and its data where processing last occurred

States of various flags and switches

Pointers to the upper and lower bounds of the memory required for the process

A list of files opened by the process

The priority of the process

The status of all I/O devices needed by the process

Each process has a status associated with it. Many processes consume no CPU time until they get some sort of input. For example, a process might be waiting for a keystroke from the user. While it is waiting for the keystroke, it uses no CPU time. While it's waiting, it is "suspended". When the keystroke arrives, the OS changes its status. When the status of the process changes, from pending to active, for example, or from suspended to running, the information in the process control block must be used like the data in any other program to direct execution of the task-switching portion of the operating system.

This process swapping happens without direct user interference, and each process gets enough CPU cycles to accomplish its task in a reasonable amount of time. Trouble can begin if the user tries to have too many processes functioning at the same time. The operating system itself requires some CPU cycles to perform the saving and swapping of all the registers, queues and stacks of the application processes. If enough processes are started, and if the operating system hasn't been carefully designed, the system can begin to use the vast majority of its available CPU cycles to swap between processes rather than run processes. When this happens, it's called thrashing, and it usually requires some sort of direct user intervention to stop processes and bring order back to the system.

One way that operating-system designers reduce the chance of thrashing is by reducing the need for new processes to perform various tasks. Some operating systems allow for a "process-lite," called a thread, that can deal with all the CPU-intensive work of a normal process, but generally does not deal with the various types of I/O and does not establish structures requiring the extensive process control block of a regular process. A process may start many threads or other processes, but a thread cannot start a process.

So far, all the scheduling we've discussed has concerned a single CPU. In a system with two or more CPUs, the operating system must divide the workload among the CPUs, trying to balance the demands of the required processes with the available cycles on the different CPUs. Asymmetric operating systems use one CPU for their own needs and divide application processes among the remaining CPUs. Symmetric operating systems divide themselves among the various CPUs, balancing demand versus CPU availability even when the operating system itself is all that's running.

If the operating system is the only software with execution needs, the CPU is not the only resource to be scheduled. Memory management is the next crucial step in making sure that all processes run smoothly.

Sorting Algorithms - Insertion sort

Insertion sort

Insertion sort is a as a stable sort. simple sorting algorithm, a comparison sort in which the sorted array (or list) is built one entry at a time. It is much less efficient on large lists than more advanced algorithms such as quicksort, heapsort, or merge sort, but it has various advantages:

Simple to implement
Efficient on (quite) small data sets
Efficient on data sets which are already substantially sorted: it runs in O(n + d) time, where d is the number of inversions
More efficient in practice than most other simple O(n2) algorithms such as selection sort or bubble sort: the average time is n2/4 and it is linear in the best case
Stable (does not change the relative order of elements with equal keys)
In-place (only requires a constant amount O(1) of extra memory space)
It is an online algorithm, in that it can sort a list as it receives it.

In abstract terms, every iteration of an insertion sort removes an element from the input data, inserting it at the correct position in the already sorted list, until no elements are left in the input. The choice of which element to remove from the input is arbitrary and can be made using almost any choice algorithm.

Sorting is typically done in-place. The resulting array after k iterations contains the first k entries of the input array and is sorted. In each step, the first remaining entry of the input is removed, inserted into the result at the right position, thus extending the result:

becomes:

with each element > x copied to the right as it is compared against x.

The most common variant, which operates on arrays, can be described as:

Suppose we have a method called insert designed to insert a value into a sorted sequence at the beginning of an array. It operates by starting at the end of the sequence and shifting each element one place to the right until a suitable position is found for the new element. It has the side effect of overwriting the value stored immediately after the sorted sequence in the array.
To perform insertion sort, start at the left end of the array and invoke insert to insert each element encountered into its correct position. The ordered sequence into which we insert it is stored at the beginning of the array in the set of indexes already examined. Each insertion overwrites a single value, but this is okay because it's the value we're inserting.

A simple pseudocode version of the complete algorithm follows, where the arrays are zero-based:

 insert(array a, int length, value) {

     int i = length - 1;

     while (i >= 0 && a[i] > value) {

         a[i + 1] = a[i];

         i--;

     a[i + 1] := value;

 insertionSort(array a, int length) {

     for (int i = 0; i < length; i = i + 1) insert(a, i, a[i]);

Good and bad input cases

In the best case of an already sorted array, this implementation of insertion sort takes O (n) time: in each iteration, the first remaining element of the input is only compared with the last element of the sorted subsection of the array. This same case provides worst-case behavior for non- randomized quicksort, which will take O(n2) time to sort an already-sorted list. Thus, if an array is sorted or nearly sorted, insertion sort will significantly outperform quicksort.

The worst case is an array sorted in reverse order, as every execution of the inner loop will have to scan and shift the entire sorted section of the array before inserting the next element. Insertion sort takes O(n²) time in this worst case as well as in the average case, which makes it impractical for sorting large numbers of elements. However, insertion sort's inner loop is very fast, which often makes it one of the fastest algorithms for sorting small numbers of elements, typically less than 10 or so.

Comparisons to other sorts

Insertion sort is very similar to selection sort. Just like in selection sort, after k passes through the array, the first k elements are in sorted order. For selection sort, these are the k smallest elements, while in insertion sort they are whatever the first k elements were in the unsorted array. Insertion sort's advantage is that it only scans as many elements as it needs to in order to place the k + 1st element, while selection sort must scan all remaining elements to find the absolute smallest element.

Simple calculation shows that insertion sort will therefore usually perform about half as many comparisons as selection sort. Assuming the k + 1st element's rank is random, it will on the average require shifting half of the previous k elements over, while selection sort always requires scanning all unplaced elements. If the array is not in a random order, however, insertion sort can perform just as many comparisons as selection sort (for a reverse-sorted list). It will also perform far fewer comparisons, as few as n - 1, if the data is pre-sorted, thus insertion sort is much more efficient if the array is already sorted or "close to sorted." It can be seen as an advantage for some real-time applications that selection sort will perform identically regardless of the order of the array, while insertion sort's running time can vary considerably.

While insertion sort typically makes fewer comparisons than selection sort, it requires more writes because the inner loop can require shifting large sections of the sorted portion of the array. In general, insertion sort will write to the array O(n²) times while selection sort will write only O(n) times. For this reason, selection sort may be better in cases where writes to memory are significantly more expensive than reads, such as EEPROM or Flash memory.

Some divide-and-conquer algorithms such as quicksort and mergesort sort by recursively dividing the list into smaller sublists which are then sorted. A useful optimization in practice for these algorithms is to switch to insertion sort for "sorted enough" sublists on which insertion sort outperforms the more complex algorithms. The size of list for which insertion sort has the advantage varies by environment and implementation, but is typically around 8 to 20 elements.

Variants

D.L. Shell made substantial improvements to the algorithm, and the modified version is called Shell sort. It compares elements separated by a distance that decreases on each pass. Shell sort has distinctly improved running times in practical work, with two simple variants requiring O(n^3/2) and O(n^4/3) time.

If comparisons are very costly compared to swaps, as is the case for example with string keys stored by reference or with human interaction (such as choosing one of a pair displayed side-by-side), then using binary insertion sort can be a good strategy. Binary insertion sort employs binary search to find the right place to insert new elements, and therefore performs comparisons in the worst case, which is Θ(n log n). The algorithm as a whole still takes Θ(n²) time on average due to the series of swaps required for each insertion, and since it always uses binary search, the best case is no longer Ω(n) but Ω(n log n).

To avoid having to make a series of swaps for each insertion, we could instead store the input in a linked list, which allows us to insert and delete elements in constant time. Unfortunately, binary search on a linked list is impossible, so we still spend O(n²) time searching. If we instead replace it by a more sophisticated data structure such as a heap or binary tree, we can significantly decrease both search and insert time. This is the essence of heap sort and binary tree sort.

In 2004, Bender, Farach-Colton, and Mosteiro published a new variant of insertion sort called library sort or gapped insertion sort that leaves a small number of unused spaces ("gaps") spread throughout the array. The benefit is that insertions need only shift elements over until a gap is reached. Surprising in its simplicity, they show that this sorting algorithm runs with high probability in O(n log n) time.

Go Apple, Young Man

Macs are making their way into the enterprise, and eWEEK Labs' Cameron Sturdevant wants to stay one step ahead of them by "going Apple." A lifelong Microsoft/PC user, Sturdevant is making the switch to be able to articulate the real benefits, drawbacks and costs of integrating the Apple/Mac platform into your organization. His journey begins here.

Once a fixture only in graphics departments and on rogue users desks (or laps), Macs are making their way into the enterprise. As a lifelong Microsoft/PC user, I ve decided to live the Mac life so that I can put both platforms in perspective in my Labs analysis and reviews.

As someone who came up through the PC platform, making the cut over to a one-button mouse and the sleek lines of the Mac interface has been a challenge, but one that I m slowly overcoming.

Most recently, I ve been testing an Apple MacBook Pro 17-inch luxury laptop, and the best way to sum up the experience thus far is that it is the ultimate in fat clients. The fact that by a few grams and even fewer millimeters it is the thinnest and lightest 17-inch system currently available in no way reduces the fatness of this lovely laptop. (For an eWEEK Labs analysis on dealing with "Mac creep" in the enterprise, click here.)

But this is far from my first experience with Apple.

It all started about two years ago when I won an Apple iPod Nano in a giveaway sponsored by Alameda County public transit. Until that time, I had staunchly resisted the iPod phenomenon and its accompanying iTunes buying mania. I just knew I d be hooked at the first obscure song download. I was unable to resist that Nano, however, and the rest is history. I ve been an iTunes user ever since, happily buying music I wouldn t have purchased in a million years in a record store.

Then my Palm Treo needed to be replaced at about the same time the first-generation Apple iPhone came out. I work next to mobile device guru Andrew Garcia, who convinced me that the iPhone was the way to go.

Those are just two examples of how Apple has been sneaking into my life, and I ve started noticing Apple devices in more places.

Up until now I ve been by default more than fervent choice a PC foot soldier in the religious wars between Mac and PCs.

Most of eWEEK s readers though the ages have been PC readers, but, then again, when I first started working here (when the publication was called PC Week, incidentally), our readers were overwhelmingly using Novell NetWare.

The times they have a-changed.

I still think the I m a Mac commercials are insufferable and the I m a PC stickers I ve seen at every Microsoft briefing I ve attended since that campaign started are needlessly defensive.

Indeed, without trying, I think I m becoming a bilingual computer user who is happy in either world.

We got a Mac mini for the lab, and that system has been transformed into my current desktop. I m using Office 2008 for the Mac to write these words, and I use Entourage to check my e-mail and track my calendar (even though I really dislike the product).

I ve become fairly adept at using a one-button mouse and at using Finder, Spotlight and Dock to quickly access the applications I need to do the research and conduct the tests that are at the center of my daily work life.

I ve also enjoyed not having to worry about virus scans or Conficker problems. That said, I m far from smug in my feeling of security on the Mac platform, mostly because I don t want to jinx my good luck.

As I continue my exploration of Apple technology in the enterprise, I m going to start probing some of the very practical questions that come with putting this fat client on corporate desktops.

First among these is the question of AppleCare in a large organization. It s clear that PC maintenance is a significant cost to organizations, and I m curious to see how the maintenance costs compare on the Mac side. I ll also be looking into how services, including warranty services for hardware, are handled for midsize to large enterprises.

Image maintenance, the real costs of maintaining two sets of desktop infrastructure support systems, and the differences in hardware and software costs are other areas I ll be exploring.

No, I m not forgetting the elephant in the room: Apple s higher equipment costs. I ll be evaluating whether this premium up-front is balanced by lifetime savings.

I invite you to come along as I take a sabbatical from the PC world (at least as far as my desktop is concerned) to see what strategic lessons can be learned for alternative desktop strategies in the not-too-distant future.

Memory - part 2

L2 cache

Most PCs are offered with a Level 2 cache to bridge the processor/memory performance gap. Level 2 cache - also referred to as secondary cache) uses the same control logic as Level 1 cache and is also implemented in SRAM.

Level 2 cache typically comes in two sizes, 256KB or 512KB, and can be found, or soldered onto the motherboard, in a Card Edge Low Profile (CELP) socket or, more recently, on a COAST ("cache on a stick") module. The latter resembles a SIMM but is a little shorter and plugs into a COAST socket, which is normally located close to the processor and resembles a PCI expansion slot. The Pentium Pro deviated from this arrangement, siting the Level 2 cache on the processor chip itself.

The aim of the Level 2 cache is to supply stored information to the processor without any delay (wait-state). For this purpose, the bus interface of the processor has a special transfer protocol called burst mode. A burst cycle consists of four data transfers where only the address of the first 64 are output on the address bus. The most common Level 2 cache is synchronous pipeline burst.

To have a synchronous cache a chipset, such as Triton, is required to support it. It can provide a 3-5% increase in PC performance because it is timed to a clock cycle. This is achieved by use of specialised SRAM technology which has been developed to allow zero wait-state access for consecutive burst read cycles. Pipelined Burst Static RAM (PB SRAM) has an access time in the range 4.5 to 8 nanoseconds (ns) and allows a transfer timing of 3-1-1-1 for bus speeds up to 133MHz. These numbers refer to the number of clock cycles for each access of a burst mode memory read. For example, 3-1-1-1 refers to three clock cycles for the first word and one cycle for each subsequent word.

For bus speeds up to 66MHz Synchronous Burst Static RAM (Sync SRAM) offers even faster performance, being capable of 2-1-1-1 burst cycles. However, with bus speeds above 66MHz its performance drops to 3-2-2-2, significantly slower than PB SRAM.

There is also asynchronous cache, which is cheaper and slower because it isn't timed to a clock cycle. With asynchronous SRAM, available in speeds between 12 and 20ns, all burst read cycles have a timing of 3-2-2-2 on a 50 to 66MHz CPU bus, which means that there are two wait-states for the lead-off cycle and one wait-state for the following three transfers of the burst cycle.

Main memory

A PC's third and principal level of system memory is referred to as main memory, or Random Access Memory (RAM). It is an impermanent source of data, but is the main memory area accessed by the hard disk. It acts, so to speak, as a staging post between the hard disk and the processor. The more data it is possible to have available in the RAM the faster the PC will run.

Main memory is attached to the processor via its address and data buses. Each bus consists of a number of electrical circuits or bits. The width of the address bus dictates how many different memory locations can be accessed, and the width of the data bus how much information is stored at each location. Every time a bit is added to the width of the address bus, the address range doubles. In 1985, Intel's 386 processor had a 32-bit address bus, enabling it to access up to 4GB of memory. The Pentium processor - introduced in 1993 - increased the data bus width to 64-bits, enabling it to access 8 bytes of data at a time.

Each transaction between the CPU and memory is called a bus cycle. The number of data bits a CPU is able to transfer during a single bus cycle affects a computer's performance and dictates what type of memory the computer requires. By the late 1990s, most desktop computers were using 168-pin DIMMs, which supported 64-bit data paths.

Main memory is built up using DRAM chips, short for Dynamic RAM.

How to Install a Front Loading Drive - part 3

Mounting the drive

Make sure the power to your computer and any external peripherals are off and your computer is unplugged from its power source. If you haven't already removed the cover from your system case, do so now.
This particular system case allows the top half of the front bezel to be detached to reveal three 5.25in external drive bays and a 3.5in bay assembly capable of holding two 3.5in devices. Remove this and remove the middle drive bay's plastic cover panel by popping it out from the bezel. If the bay is also covered by a metal plate, remove this by carefully twisting it back and forth until it breaks off. Be careful of the newly exposed metal were the grills were attached as these areas are likely to be sharp.
Determine if you must install mounting rails on the sides of your drive. To do so, insert the drive into the open bay. If the drive fits tightly with little or no clearance on either side of the drive, the drive can be mounted directly into your computer, without the use of drive rails.
If you must use mounting rails, screw the rails into the lower pair of holes on either side of the drive. Make sure the metal portion is angled away from the device and facing forward. Check their positioning by sliding the drive into the bay. If necessary remove the mounting rails and fix them to the the other pair of holes.
When it's apparent that the mounting rails are correctly positioned, push the drive into the bay until you hear a click, indicating that the dive has properly located.

How to Install a Front Loading Drive - part 9

Making the connections

A floppy disk drive's connectors are at the back of the unit.

Controller connector:

The floppy drive connector looks similar to a 40-pin IDE connector, but is a little smaller with a pin count of 34.

However, as with an IDE cable, the convention is for Pin 1 on the connector to correspond with the red wire of the floppy drive ribbon.

This applies with rounded floppy cables - as we're using here - as well as the more conventional floppy ribbon cable.

Connect the floppy drive ribbon between the drive and the the floppy drive connector on the motherboard - next to the pair of IDE controllers - making sure to similarly align the red line up with Pin 1 on the motherboard connector. These days both connectors and cables are keyed to prevent them being inserted the wrong way round.

A standard 5-connector floppy ribbon cable is a far more complex looking beast.

At one end is a 34-pin header connector for connection to the motherboard floppy disk controller. In the middle and at the opposite end of the cable are two pairs of connector, each comprising a 34-pin header type connector for use with a modern day 3.5in floppy drive and a larger card edge connector - used in bygone days by older 5.25in floppy disk drives.

However, it is the twist in the cable that effectively reverses the signals sent by a group of seven of the cable's wires, immediately before the end pair of connectors, that characterises a conventional floppy drive ribbon cable.

Historically, floppy drives used a drive select (DS) jumper to configure the drive as either the A: or B: drive in the system. These days floppy drives come preconfigured as :B drives and its the floppy cable itself that determines how the system sees the drive.

A drive connected to the middle connector will be seen as it's been configured, namely as a :B drive. However, a drive connected to the end connector will effectively have it's drive letter designation reversed by the twist in the cable, so that it's recognised as an :A drive.

Power connector:

The small white connector to the left of the controller connector is the drive's power connector.

Connect this to a spare small female 4-pin white connector from the power supply.

Again, the connector and receptacle are keyed to prevent insertion the wrong way round.

Configuring your BIOS

If a Master or Slave device is set to Disable or None or a similar designation, change it as appropriate to Enable or Auto (or something similar, depending on your setup program).

Some BIOSes have a feature that renders a drive's location in relation to the ribbon twist irrelevant. Make sure this is not enabled, else a drive connected to the floppy cable after the twist may not be recognised as your A: drive.

Save the settings and exit the setup routine, allowing the system to continue to boot.

The BIOS should now automatically detect the new drive.When Windows has loaded you can confirm that it has by going to My Computer where you should see the new drive identified. The particular drive letter assigned will depend on your machine's configuration.

Compaq - Armada M300 Review

Compaq's Armada M300 sub-notebook has been updated, and now uses a 600MHz Intel Mobile Pentium III processor. Ultra thin, and ultra light, the M300 itself is only 2.7cm high and weighs just 1.4kg.

Users needing a floppy disk or DVD/CD-ROM drive (the standard unit has neither) can buy either dedicated external units or Compaq's Mobile Expansion Unit (MEU), which when docked forms a two-slice, three-spindle system. Even this combined unit is only 5cm high, with a total weight of around 2.5kg.

The standard four-cell battery gives a pitiful life of just over one and a half hours, although a useful charge meter is incorporated into the battery. A longer life battery is available as an option - and it's one we'd recommend. The cylindrical battery pack attaches below and to the rear of the top slice, and can also be used to provide a different keyboard angle if rotated downwards to rest on a flat surface.

The M300 we reviewed had a 12GB hard disk and an 11.3-inch TFT screen driven by a 4MB ATI Rage LT Pro. A V.90 modem/NIC combination Mini-PCI card is installed, freeing up the single Type II PC Card slot for other uses, and there are the usual ports, including line-in/line-out jacks, parallel, serial, video-out and USB ports.

These ports are duplicated on the MEU, with the exception of the modem/LAN ports, plus there are dedicated PS/2 mouse and keyboard ports on this expansion pack. The MEU that came with the M300 reviewed was supplied with a standard floppy drive and a Compaq 24-speed CD-ROM drive.

Although a little slow compared to the other systems here - only the standard 64MB of memory was fitted - this is a well-designed and useable platform. Definitely go for the bigger battery, though.

Compaq - Armada M300 price

1,855 + VAT (includes the MEU)

Compaq: 0845 2704002

www.compaq.co.uk

Guide to Buying a Webcam

How web broadcasting works

Webcams are those handy little cameras that attach to your PC and send images to a web page that can be viewed by others. This enables you to share daily life events with friends and family in other parts of the country or the world, or to arrange a video-conference with colleagues and maintain long distance relationships of all kinds. Of course the number of ways to use this technology is limited only by your imagination.

Web Cameras

But before you buy a webcam, it pays to understand a little about how the technology of broadcasting images over the Internet works. Of course, if you're a full bottle on this already, you can skip this section and go straight to browsing the options on Myshopping.com.au where you can compare products and suppliers, their specifications and prices.

Webcams provide 'real time' images of people; places and events that can be viewed 'live' on a web page. The broadcasting end has a camera that captures the images, feeds them into a computer to an ISP and out to viewing pages across the Internet. There are two different types of broadcast: streaming images, where the images are a constant stream downloaded in video format; or Java, where the images are captured at fixed time intervals and refreshed on the web pages at a rate fixed by the broadcaster.

The Applications - What are you intending to broadcast, and to whom?

There is a wide range of uses of webcam technology. Some examples include personal 'Big Brother' style diaries, sharing of family events, workplace security, video conferencing, virtual tourism, road traffic management, weather watching, event broadcast and a host of others.

Before you make a choice about any webcam equipment, it helps to decide exactly how you want to use the technology, in other words, what you are intending to broadcast. This decision will impact upon the type of camera you use, and how you use it.

A second consideration is, who will be viewing your content? What level of quality is expected? This will help determine the type of camera you use, the software involved and your Internet connection. Of course, your Internet connection may be a limitation on how much you can do.

The requirements for video conferencing are different from the requirements of workplace security, which are different again from the requirements of sharing a family event.

The physical components

There are a number of physical components required to make web cam technology work. At the top of the list is the camera itself. Then, depending on the type of camera you use and the way in which you want to deliver the content to the Internet, you may need to incorporate video capture hardware in your computer. Some software is required to help you process the data, and Internet connection is required and a web page into which the data is fed.

CAMERA CHOICES

Your choice of camera depends somewhat on what you are intending to show. If you need to reach a large public audience yo may want good quality camcorder or megapixel camera that captures high quality images. If it's just for seeing who's at your front door or keeping an eye on the kids in their playroom, then it may not need to present high quality images. If you are intending to use it outdoors, it will need to be weather proof and you may need to consider sun and UV protection. Available power supply and any robotic requirements for camera movement and focus are extra considerations.

Dedicated webcams

The most basic webcams connect to a PC using a simple USB connection. A wide range of cameras with accompanying software at a range of prices is available for this type of application. Simply search though Myshopping.com.au to compare prices and specifications. Dedicated webcams are simple to install and easy to use, but come with limitations that affect the quality of the images, such as low number of frames per second (refresh rates) and resolution (pixels per inch).

Camcorders and security cameras

Higher quality images and more camera control come from using camcorder and security cameras. To use these devices you will need to add a video capture card to your PC. Once you have that installed however, you can use a wide range of cameras from broadcast cameras to miniature spy cameras. You can include variable lens options, filters for daylight and low light situations, as well as robotic controls for panning and focus adjustments. You can search through Myshopping.com.au for camcorder selections.

Integrated cameras

An integrated camera combines the camera and the optical hardware with a video server, and as such requires no additional software. They can be used in network situations or as stand-alone devices for monitoring progress on a construction project for example.

Megapixel cameras

Network megapixel cameras combine network capability with high quality digital camera technology. These cameras offer excellent quality but this creates large files sizes, therefore they have limited application in constant streaming video. However for interval refreshed archive image collection, they are ideal, providing a constant record and high quality. You can search through Myshopping.com.au for digital camera selections.

SOFTWARE

If you are not using an integrated camera solution, you will need to install an encoding program like Webcaster or MediaCaster to transfer your images to a web page.

At the receiver end, when web surfers browse the internet and wish to view live video on the web for the first time, they will need to download dedicated applications that show the content such as an ActiveX control, Windows Media player, Flash player or the like.

INTERNET CONNECTION

Finally, you need an Internet connection. The hardware you will need may include a modem for dial-up connection, or modem/router for a broadband solution. Naturally the higher the quality you want, or the faster refresh rate you want, the more bandwidth you will need. ADSL (Broadband) is going to offer you the best solution, but keep in mind what your Internet connection when you are making choices of cameras and feeder software.

Webcam applications work well with wireless solutions. Make sure when you are purchasing a camera or network video solution that it is compatible with any wireless system you may be using in a LAN.

Key considerations

The specifications that are variable with webcam applications, and are affected by camera type, web interface and Internet connection, include the number of frames per second and the image resolution.

Frames-per-second is the number of times a still image flashes by in a second to give the appearance of moving pictures. In Australia, the standard television PAL format is at 25 frames per second. A webcam with up to 30 frames per second will show normal video images. But the more frames per second you demand, the more bandwidth, memory and processing power is required.

Resolution is measured the number of pixels per inch. High quality photographs require a high resolution. But the standard for web images is a low 72 dpi. Higher resolution images will not be of any better visual quality, just slower to upload and download.

CPU Technology - part 5

AMD Mobile K6 CPUs

Just as the desktop version of its K6-2 processor with 3DNow! technology stole a march on Intel by reaching the market well before its Pentium III was able to offer similar 3D capability via its "Katmai New Instructions", AMD's Mobile K6-2 enjoyed a similar advantage in the notebook arena, having succeeded in getting a number of major notebook OEMs - including Compaq and Toshiba - to produce systems based on its mobile K6 family by early 1999.

AMD's K6 mobile processors were available in Socket 7 and Super7 platform-compatible, 321-pin ceramic PGA packages or BGA packages for smaller form factors and at speeds of 266MHz, 300MHz and 333MHz. The Mobile K6-2 operated at a core voltage of 1.8V and dissipated less than 8 Watts of power running typical applications.

The Mobile K6-2 family of processors was later complemented by the higher performance AMD K6-2 P range - both processor families sharing a number of performance-boosting features, including AMD's 3DNow! technology and support for Super7 notebook platforms that implemented leading-edge features, such as a 100MHz FSB, 2X AGP graphics, and up to 1MB of Level 2 cache. By the autumn of 1999 the Mobile AMD-K6-2-P range had been extended to include a 475MHz version - at the time the highest clock speed CPU available for x86 notebook computing.

Mid-1999 saw the announcement of the Mobile K6-III-P processor based on AMD's advanced sixth generation microarchitecture and sporting AMD's unique TriLevel Cache design. This comprised a full-speed 64KB Level 1 cache, an internal full processor-speed backside 256KB Level 2 cache, and a 100MHz frontside bus to an optional external Level 3 cache of up to 1MB. The 21.3-million transistor Mobile AMD-K6-III-P operated at a core voltage of 2.2V and was manufactured on AMD's 0.25-micron, five-layer-metal process technology. Originally available at a clock speeds of up to 380MHz, the range had been extended to a maximum speed of 450MHz by the autumn of 1999.

In the spring of 2000, the announcement of its Mobile AMD-K6-III+ and Mobile AMD-K6-2+ processor families at speeds up to 500MHz saw AMD's mobile processors make the transition to 0.18-micron process technology. Early the following year, the company achieved another significant first, with the announcement of the first seventh-generation processors - the 600MHz and 700MHz Mobile Duron CPUs - to enter the notebook market.

Mobile Pentium III

The October 1999 announcement of a range of 0.18-micron Pentium III processors included the launch of the first mobile Pentium IIIs. The new processors - available at speeds of 400MHz, 450MHz and 500MHz and featuring a 100MHz system bus - represented a significant performance boost of up to 100% over Intel's previous fastest mobile CPU.

All mobile processors consume less power than their desktop counterparts, are significantly smaller in size and incorporate sophisticated power management features. The smallest processor package of the day - the BGA - is about the size of a postage stamp and the 400MHz processor - operating at an extremely low 1.35V - was targeted specifically at mini notebook designs.

Mid-2001 saw an important step in the evolution of Intel's family of mobile CPUs, with the introduction of the Pentium III-M processor, based on Intel's new 0.13-micron Pentium III core known internally as the Tualatin. By this time the introduction of new CPU technologies and manufacturing processes in low volume markets first, and only later - after sufficient time to perfect the associated technologies - adapting them to mass production segments, had become a well-established practice. The Tualatin was a further case in point even though - by the time of its much delayed appearance - deployment in the mobile arena was its primary purpose.

By the spring of 2002 a wide range of Tualatin-based Pentium III-M CPUs were available. The spectrum of core voltages accommodated was between 1.1V and 1.4V at clock frequencies of up to 1.2GHz for standard voltage versions and 866MHz and 766MHz for low voltage and ultra low voltage versions respectively.

Step by Step instructions On How to Remove Spyware, Malware, and

Step by Step instructions On How to Remove Spyware, Malware, and Viruses From Your Computer

In case you suspect you have a virus (or any other malware), you ought to take steps immediately, often times such issues occur and system slow downs due to registry errors receive a nice registry cleaner and computer optimizer from Intel Directory . The following procedures
work for most malware (except perhaps for new, unknown or unusually malignant strains). It is better to complete all steps, so you can be (reasonably) sure that all traces have been removed.

Signs to look out for (infections may cause one or several of the following):
Slow computer, and/or slow web connection.unusual pop-ups or web browser redirections (beyond those expected from dodgy websites).
Program failure, or inexplicable errors (even after a fresh install).
System functions unavailable (eg: Control Panel, Task Manager, web Explorer).
System giving a "RPC error", giving a window with a 30 second countdown to a restart.
Excessive web cap usage, i.e high web traffic on your computer.

1. Run your virus-scanner, but beware, lots of modern viruses can circumvent (or hide from) anti-virus programs. Quarantine anything suspicious.

In case you do not have or your antivirus has expired uninstall first and download avg free

Tips

2. Install MalwareBytes Anti-Malware and update it. Don't scan for malware yet.
3. Install Spy Bot[1] and update it. Don't scan for malware yet.
4. Reboot in to Safe Mode - Restart your computer and press F8 before
Windows lots. Press F8 several times in case you need to. Select Safe
Mode from the resulting menu. Safe Mode disables much of the startup
routine (including some common Malware hiding places).
5. Run your Malware Scanners - Run both the scanners sequentially,
deleting any references found.
6. Enjoy your sanitised computer.

Warnings

If these steps are difficult to follow or impossible to achieve, call a computer service professional. Booting in Safe Mode is important if the malware is difficult to
remove normally. If this technique fails to clean your computer, download HijackThis, run and save a log, and then post the log to a reputable security forum such as BleepingComputer or GeekstoGo.

It is always safer to call on a computer expert such as MDofPC Custom Computers LLC to perform procedures that you are not sure about. There is always a chance that you could disable your system and lose valuable information. Removing malware often takes hours, days, or even weeks. Be sure you have lots of time available. Securely wipe your free space with file shredding application after the removal is complete to avoid unauthorized or bad people restoring
the deleted virus file with any information recovery application.

How to Install a SCSI Device - part 6

Making the connections

Squeeze either side of the connector to connect the supplied SCSI cable to the SCSI host adapter card's external SCSI connector.

Connect the other end to the scanner's 50-pin DB50 connector ...........

............ and plug in the power adapter power cord

The proliferation of SCSI standard versions over the years has led to a situation in which there exist many different types of SCSI cables and connectors. Whilst each new version of SCSI is backwards compatible, it can require a bewildering array of cables, connectors and adapters to connect together a bunch of SCSI peripherals that spans multiple variants of the standard:

Host or Host Adapter	Connector
50-pin Centronics: Most SCSI SLOW (5 MBps) computers and host adapters use the Centronics-type 50-pin connector. Also some 8-bit Fast computers and host adapters.
DB25: Apple/Mac and some older Sun 8-bit workstations.
DB50: Old Sun and DG Computers, Zip drives and many scanners.
HD50: Many 8-bit SCSI FAST (up to 10 MBps) computers and host adapters use this 50-pin High-Density connector.
HD68: All FAST/WIDE (16-bit) SCSI-3 computers and host adapters plus old DEC single-ended SCSI use this 68-pin High Density connector.
SCA80: New Single Connector Attachment 80-pin connector used for Ultra2Wide/LVD, Ultra160 and Ultra32O applications

It's possible to connect a number of SCSI devices by creating a "daisy-chain", that is, plugging one device into the next.

The last device in the chain needs to terminated.

In this case, since it's going to be the only external SCSI device, the SCSI terminator the scanner was supplied should be left in place.

To ensure reliable communication on the SCSI bus, the end of the chain of devices on the SCSI bus must be properly terminated with resistors to prevent signal reflections and guarantee data integrity over long cable lengths.

In fact, there may be one or two chains. One is the external chain from the external port on the SCSI adapter card, the other is the internal chain, connected from the card's internal SCSI connector. Termination is accomplished by the peripheral at the end of each cable - or the end of the cable itself - having a terminator installed (or enabled). It is important for devices between the ends of each cable to have their terminators removed (or disabled).

Here are some general guidelines for termination:

Termination on internal SCSI peripherals usually is controlled by manually setting a jumper or a switch on the peripheral, or by physically removing or installing one or more resistor modules on the peripheral.
Termination on external SCSI peripherals usually is controlled by installing or removing a SCSI terminator. On some external peripherals, termination is controlled by setting a switch on the back of the drive.
By default, termination on SCSI host adapter card themselves is automatic.
Internal Ultra2 peripherals are set at the factory with termination disabled and cannot be changed. Proper termination for internal Ultra2 peripherals is provided by the built-in terminator at the end of the Ultra2 internal SCSI cable.
Most non Ultra2 SCSI peripherals come from the factory with termination enabled.

AJP - 3300C Review

In the past, when Taiwanese manufacturers have tried to squeeze a desktop processor into a bulky laptop system the end result has invariably been horrific in pretty much all respects. Not so with this model from AJP. Although it sports a 750MHz desktop Pentium III, heat levels are kept low thanks to a large fan fitted in the system's base. While it might be reasonable to guess that this would put a terrific strain on the battery, you'll be surprised to find that the machine can run for around two and a quarter hours before it needs to be recharged. This is hardly the best battery life we've seen but for such a high spec system it's not half bad.

Our review system was fitted with 128MB of PC100 memory which can be expanded to a maximum of 256MB. The hard drive is certainly the main limiting factor as far as performance is concerned; it's a 12GB Fujitsu device with a 4200rpm spin speed and 1MB buffer. Most desktops with similar specifications will be running 5400/7200rpm drives and if the AJP were fitted with a faster drive (IBM produce 5400rpm notebook drives) it would certainly gain the extra edge it needs to bring its performance into line with desktops. The security conscious among you will be pleased to hear that the hard drive can be flipped out without a screwdriver, making it easy to secure your data when the laptop is not in use.

To a lesser extent the graphics subsystem also holds back system performance, but not by much. The system uses an ATI Rage LT Pro AGP2x chip with 8MB of video memory and while this offers enough 2D performance to match desktops, the 3D acceleration is virtually non-existent. But we're particularly impressed by the 14.1inch TFT screen which offers an extremely bright image.

Although there's no built-in modem, our system was bundled with a 56Kbps PC Card device which is included in the price. And while the AJP is far from feather-light, at 3.3kg it doesn't really qualify as overweight when compared to more conventional high end notebooks.

AJP - 3300C features - Verdict

As mentioned above, this notebook's performance is only slightly lower than that of similarly specified desktop machines, and this can be attributed almost entirely to the hard drive. However, it is worth noting that the gap between desktop and mobile processors is closing all the time. Systems based on new mobile Pentium processors don't lag that far behind this machine and offer superior battery life, lower weight and often lower prices. Just as notebook manufacturers have successfully put a desktop processor into a laptop machine, mobile processor manufacturers may have made it pointless to do so.

AJP - 3300C price

1,674 + VAT

AJP: 020 8208 9700

VDI - Reducing Desktop Costs

The traditional PC as the corporate thick client has long been at the forefront of desktop computing. It has represented a favourable compromise between functionality, performance and cost. However, a number of challenges remain:

Desktop Management: Centralising desktop management is an extremely difficult task in the face of a broadly distributed computing environment and the corporate workforce, who increasingly require secure on-demand access to their desktop environment from anywhere. Furthermore, desktops are notoriously difficult to standardise because of the variety of PC hardware and users needs to modify desktop environments.

Total Cost of Ownership: The relatively low cost of PC hardware is often more than offset by the high cost of PC management and support. Ongoing PC management including deployment of software, updates and patches can be labour-intensive and time consuming because of the need to test and validate deployments for a wide variety of PC configurations. Likewise, the lack of standardisation and the need for support personnel to troubleshoot issues in person and on-site raise support costs dramatically.

Data Security: Ensuring that data on PCs is successfully backed up and can be restored when PCs fail or files are lost is a significant challenge. Even when data is successfully backed up, the risk of PC theft threatens the security of important data.

Low Resource Utilisation: The distributed nature of PCs makes it difficult to pool resources to improve utilisation and reduce costs. As a result, PCs are often less than five percent utilised, remote offices require duplicate desktop infrastructures, and remote desktop solutions may be required for mobile workers.

According to Wikipedia, Virtual Desktop Infrastructure (VDI) is a server-centric computing model that borrows from the traditional thin-client model but is designed to give system administrators and end users the best of both worlds: the ability to host and centrally manage desktop virtual machines in the data centre while giving end users a full PC desktop experience.

This form of desktop virtualisation provides many advantages, including:

Instant provisioning of new desktops

Near-zero downtime in the event of hardware failures

Significant reduction in the cost of new application deployment

Robust desktop image management capabilities

Normal 2-3 year PC refresh cycle extended to 5-6 years or more

Existing desktop-like performance including multiple monitors, bi-directional audio/video, streaming video, USB support etc.

Ability to access the users enterprise desktop environment from any PC, (including the employee s home PC)

Desktop computing power on demand

Multiple desktops on demand

Self provisioning of desktops (controlled by policies)

Why would your computer not boot up?

When Windows fails to boot it is normally caused by a user installing a program or device and it has caused a conflict with one or more other programs. This will no doubt give you plenty of heartache if you're not certain which program caused Windows to not boot up.

If you recently installed a program or application and know where it was installed,you may be in much better shape as for as correcting the error. Here are common ways to correct the problem of your computer not completely booting up or not booting up at all.

If your computer will not boot-up at all,hopefully you have made a good emergency boot disk. You can always make a windows startup disk by creating one from another computer running Windows 98 or Me.Perform the following if your computer won't Boot-Up At All.

FIRST......Put your boot floppy disk in the floppy drive and turn on the PC.On some computers, you may have to access the bios and select the Boot priority to your A: drive.Save any changes and select "Start Computer without CDROM support" and press Enter.Once you are at the A prompt,type dir c: and press enter.

If your programs and other files are present,try restoring your system Registry by following the steps below.This may repair Windows,the Config. Sys and autoexec.bat files to where the PC may boot up normally.When the files are present,its a good indication of a good hard drive.

SECOND......To correct the problem of your computer not booting up,type in "fdisk /mbr" and press Enter to restore your master boot record.Type "Scandisk C:" to check the hard drive for errors that have occurred. You can also type "Sys C:" to hopefully restore files needed to boot up your computer.

THIRD......If the above procedures fail to repair your computer,you can repeat the first part of step one above and select "Start Computer With CDROM Support" re-install Windows.

Making A Windows XP Bootable Floppy Windows XP users should create a boot disk now by placing a formatted blank diskette in the A: drive, open Windows Explorer to the C:,select Tools,Folder Options ,show Hidden files and and folders,then View Tab. Now you uncheck "Hide Protected Operating System Files (recommended).You will see a warning and click Yes and click OK.Copy the files ntldr,ntdetect.com and boot.ini onto the disk.Remove the disk and label it the Windows XP Boot Disk.

After making your boot disk,recheck "Hide protected operating system files and folders (recommended)" in the Folder Options dialog box. To use the disk when Windows XP won't boot,place the disk in the drive,and unto re-booting,the computer, Windows simply bypass the basic boot files on the hard drive and continue to boot up.

If The PC Won't Boot Pass Windows

FIRST......If your Operating System is Windows Millennium,turn on the computer and immediately press and hold down the CTRL key.Once the startup options appear,release the CTRL key. Select Safe Mode and press Enter.You are now in Windows limited version.If you know what caused your computer not to boot,you can now either change or delete that program.

SECOND....Repair your Registry by selecting Start,Run and typing "scanregw /fix" and press enter.This will fix any damage done to the Registry. You can also restore your registry which replaces your current registry with an earlier copy that was backed up by your computer.Click on Start,Run and type "scanregw /restore and press Enter.

To repair your Windows 98 Registry,hold down the CTRL key as you start the PC and select "Command Prompt Only".Type "scanreg /fix" and press Enter and "scanreg/restore" to restore a previousely saved copy of the Registry.

If you have Windows XP,press F8 after rebooting the PC should Windows freeze while booting up. You can select "Last Known Good Configuration" after rebooting to allow the computer to boot the last backed up files.And you can choose "Safe Mode" to remove any files you know caused the operating system to hang up.

Be prepared when your operating fails to boot. It would be a great idea to go over this article a few times and print it.Make yourself s notebook and place this and all related articles there.

If your computer fails to boot or begins to become unstable,you can refer to these articles to make corrections that are needed.Learn these steps from your television set with the PC Super Pack.

Be sure to note any changes you make to your Registry and if you're not sure,its best to find a friend that's pc savvy first.Above all,be certain you back up your registry before making any changes and know how to restore as well

Acer - TravelMate 610 Review

Acer's new TravelMate notebook is a slimline 2-spindle machine measuring 33mm thick when closed and weighing only 2.3kg, which makes it a suitable choice if you are planning to travel with it. The core specification is pitched about right for a fully portable notebook, with an 800MHz Pentium III SpeedStep processor doing the work, backed by the now more-or-less standard helping of 128MB of PC133 SDRAM.

A removable 20GB IBM Travelstar hard disk provides a sensible amount of storage and the system is shipped with the choice of either an 8-speed Toshiba DVD-ROM drive or a CD-RW drive in its multipurpose bay. You don't get a floppy drive as standard though - an external-only USB module is available for 79 plus VAT, adding some 350g to the overall carrying weight.

Like most of the brand-name notebook manufacturers, Acer has devoted some energy to the design aesthetics of its products, and the TravelMate is both distinctive and attractive to look at. Its signature feature is the curved layout of the keyboard; this, if anything, slightly improves the ergonomics, which are fairly good anyway thanks to a sensible layout that makes use of large keys where they are needed.

This notebook is also solidly put together, and incorporates sensible features for a travelling machine like shock shielding over the hard disk compartment and a metal alloy lid to protect the screen.

The TravelMate lacks parallel and serial ports, but both are supplied on a short adapter cable that plugs in to an expansion bus. This can also be used with the optional port replicator. You don't get Firewire, but the machine does have two USB ports, plus a standard PS/2 input for an external mouse or keyboard, and a single Type II PC Card slot for expansion. It's unlikely that you'll notice the lack of a second PC Card slot as both a V.90 Lucent modem and an Intel Pro/100 VE 10/100 network adapter are built in.

The motherboard is based around Intel's 815EM chipset, which incorporates a graphics processing element and, in this case, 4MB of dedicated display cache memory. It also borrows from main system memory like other members of the i815 family, but the presence of dedicated memory boosts graphics performance measurably. Although it's a fairly compact machine the designers have managed to squeeze in a 14.1-inch TFT display, which proved to be bright and comfortably readable running in its native 1024 x 768 resolution.

But the most unusual feature of this notebook has to be its smart card security system, which can be configured to provide several layers of protection against unauthorised use. You can implement a BIOS lock which will not allow the machine to boot at all unless the correct card is inserted in the slot in the left side of the case, and you can follow up with a Windows login password, again requiring the presence of the correct card for it to work.

It's also possible to encrypt files and folders, with the smart card and password required to unlock them, so all in all there's enough to keep data safe from all but the most determined corporate or political espionage agents.

Battery life seems to average about two hours, which is a little less than ideal, but overall performance is quite good for a PIII/800 notebook. Since the price isn't by any means wildly inflated by the standards of corporate notebooks, the pieces all fall into place rather nicely. The TravelMate 610 is well worth a closer look if you are trying to find a lighter notebook for travelling use. And if security features are a concern, it really should be on your shortlist.

Acer - TravelMate 610 features - Verdict

The inclusion of smart card security makes an already good notebook even better, particularly for business use. High overall quality, manageable weight and dimensions, and an international one year warranty are among the TravelMate 610's other notable features.

Acer - TravelMate 610 price

1,349 + VAT

Acer UK: 0870 900 2237

www.acer.co.uk

Synchronize your PDA With Your Desktop Computer

Being able to synchronize your PDA with your computer allows you to back up information should you need to. Synchronization is also effective if you need to get information off of your PDA in order to free up some of the memory space on your PDA.

Every PDA available today can be synchronized with your desktop computer. This is an important program or function that allows you to add data to your PDA. Your PDA could come with the docking station that plugs into your desktop computer, while some docking stations for specific PDA's are sold separately. Either way you want to be sure you have the right one.

With synchronization you can also load emails and other items onto your PDA to read them at a later time. It also keeps you up to date , with any appointments or details concerning your calendar of events on your PDA. The file manager on your PDA, knows whenthe PDA itself has actually been docked to a desktop computer and will begin to synchronize information. There is a program that comes with your docking station or PDA for the desktop computer to acknowledge the PDA and its source.

If synchronization starts automatically you have to be careful, in some ways because the PDA will attempt to load files on its own that you may not want on the PDA in the first place. You should create a special folder on your desktop computer for your PDA to keep track of your information.

One point that is definite, if you do not create a file and you synchronize your PDA with your desktop computer specifying what folder to sync with your PDA will attempt to synchronize and every folder on your desktop computer it can. You have to be specific in this area, or your memory on your PDA will fill up a lot faster than you had wanted it too. And, with information you didn't want on your PDA to begin with. Some people change the settings on their PDA so is doesn't automatically start to synchronize with your computer as soon as it is docked with your desktop, doing this basically makes the PDA from a command from you before it starts to synchronize the folders.

Also, in the event your PDA gets lost or stolen, you have the information on your desktop computer and that data as well as maybe pictures or mp3's aren't lost. You synchronized the information with your PDA. Most PDA's already have the synchronization program on them, therefore all you have to do is install the program on your desktop computer for the synchronization process to work using your PDA.

Byte Prefixes and Binary Math

When you start talking about lots of bytes, you get into prefixes like kilo, mega and giga, as in kilobyte, megabyte and gigabyte (also shortened to K, M and G, as in Kbytes, Mbytes and Gbytes or KB, MB and GB). The following table shows the binary multipliers:

Name	Abbr.	Size
Kilo	K	2^10 = 1,024
Mega	M	2^20 = 1,048,576
Giga	G	2^30 = 1,073,741,824
Tera	T	2^40 = 1,099,511,627,776
Peta	P	2^50 = 1,125,899,906,842,624
Exa	E	2^60 = 1,152,921,504,606,846,976
Zetta	Z	2^70 = 1,180,591,620,717,411,303,424
Yotta	Y	2^80 = 1,208,925,819,614,629,174,706,176

You can see in this chart that kilo is about a thousand, mega is about a million, giga is about a billion, and so on. So when someone says, "This computer has a 2 gig hard drive," what he or she means is that the hard drive stores 2 gigabytes, or approximately 2 billion bytes, or exactly 2,147,483,648 bytes. How could you possibly need 2 gigabytes of space? When you consider that one CD holds 650 megabytes, you can see that just three CDs worth of data will fill the whole thing! Terabyte databases are fairly common these days, and there are probably a few petabyte databases floating around the Pentagon by now.

Binary math works just like decimal math, except that the value of each bit can be only 0 or 1. To get a feel for binary math, let's start with decimal addition and see how it works. Assume that we want to add 452 and 751:

  452
 + 751

  ---
  1203

To add these two numbers together, you start at the right: 2 + 1 = 3. No problem. Next, 5 + 5 = 10, so you save the zero and carry the 1 over to the next place. Next, 4 + 7 + 1 (because of the carry) = 12, so you save the 2 and carry the 1. Finally, 0 + 0 + 1 = 1. So the answer is 1203.

Binary addition works exactly the same way:

  010
 + 111

  ---
  1001

Starting at the right, 0 + 1 = 1 for the first digit. No carrying there. You've got 1 + 1 = 10 for the second digit, so save the 0 and carry the 1. For the third digit, 0 + 1 + 1 = 10, so save the zero and carry the 1. For the last digit, 0 + 0 + 1 = 1. So the answer is 1001. If you translate everything over to decimal you can see it is correct: 2 + 7 = 9.

To see how boolean addition is implemented using gates, see How Boolean Logic Works.

To sum up, here's what we've learned about bits and bytes:

Bits are binary digits. A bit can hold the value 0 or 1.

Bytes are made up of 8 bits each.

Binary math works just like decimal math, but each bit can have a value of only 0 or 1.

There really is nothing more to it -- bits and bytes are that simple.

Interfaces - part 2

ISA bus

When it appeared on the first PC the 8-bit ISA bus ran at a modest 4.77MHz - the same speed as the processor. It was improved over the years, eventually becoming the Industry Standard Architecture (ISA) bus in 1982 with the advent of the IBM PC/AT using the Intel 80286 processor and 16-bit data bus. At this stage it kept up with the speed of the system bus, first at 6MHz and later at 8MHz.

The ISA bus specifies a 16-bit connection driven by an 8MHz clock, which seems primitive compared with the speed of today's processors. It has a theoretical data transfer rate of up to 16 MBps. Functionally, this rate would reduce by a half to 8 MBps since one bus cycle is required for addressing and a further bus cycle for the 16-bits of data. In the real world it is capable of more like 5 MBps - still sufficient for many peripherals - and the huge number of ISA expansion cards ensured its continued presence into the late 1990s.

As processors became faster and gained wider data paths, the basic ISA design wasn't able to change to keep pace. As recently as the late 1990s most ISA cards remained as 8-bit technology. The few types with 16-bit data paths - hard disk controllers, graphics adapters and some network adapters - are constrained by the low throughput levels of the ISA bus, and these processes can be better handled by expansion cards in faster bus slots. ISA's death-knell was sounded in the PC99 System Design Guide, co-written by the omnipotent Intel and Microsoft. This categorically required the removal of ISA slots, making its survival into the next millennium highly unlikely.

Indeed, there are areas where a higher transfer rate than ISA could support was essential. High resolution graphic displays need massive amounts of data, particularly to display animation or full-motion video. Modern hard disks and network interfaces are certainly capable of higher rates.

The first attempt to establish a new standard was the Micro Channel Architecture (MCA), introduced by IBM. This was closely followed by Extended ISA (EISA), developed by a consortium made up of IBM's major competitors. Although these systems both operate at clock rates of 10MHz and 8MHz respectively, they are both 32-bit and capable of transfer rates well over 20 MBps. As its name suggests, an EISA slot can also take a conventional ISA card. However, MCA is not compatible with ISA at all.

Neither system flourished, largely because they were too expensive to merit support on all but the most powerful file servers.

Local bus

Intel 80286 motherboards were capable of running expansion slots and the processor at different speeds over the same bus. However, dating from the introduction of the 386 chip in 1987, motherboards provided two bus systems. In addition to the "official" bus - whether ISA, EISA or MCA - there was also a 32-bit "system bus" connecting the processor itself to the main memory. It was the rise in popularity of the Graphical User Interface (GUI) - such as Microsoft Windows - and the consequent need for faster graphics that originally drove the concept of local bus peripherals. The bus by which they were connected was commonly referred to as the "local bus" because its high speed and the delicate nature of the processor means that it can only function over short distances.

Initial efforts to boost speed were proprietary: manufacturers integrated the graphics and hard disk controller into the system bus. This achieved significant performance improvements but limited the upgrade potential of the system. As a result, in the early 1990s, a group of graphics chipset and adapter manufacturers, the Video Electronics Standards Association (VESA), established a non-proprietary high-performance bus standard. Essentially, this extended the electronics of the 486 system bus to include two or three expansion slots: the VESA Local Bus (VL-Bus). The VL-Bus worked well and many cards became available, predominately graphics and IDE controllers.

The main problem with VL-Bus was its close coupling with the main processor. Connecting too many devices risked interfering with the processor itself, particularly if the signals went through a slot. VESA recommended that only two slots be used at clock frequencies up to 33MHz, or three if they are electrically buffered from the bus. At higher frequencies no more than two devices should be connected, and at 50MHz or above they should both be built into the motherboard.

The fact that the VL-Bus ran at the same clock frequency as the host CPU became a problem as processor speeds increased. The faster the peripherals are required to run, the more expensive they are, due to the difficulties associated with manufacturing high-speed components. Consequently, the difficulties in implementing the VL-Bus on newer chips such as the 40MHz and 50MHz 486s and the new 60/66MHz Pentium created the perfect conditions for Intel's PCI (Peripheral Component Interconnect).

Leave It On Or Turn It Off?

One of the oldest unresolved controversies in the computer world is: Should you leave your computer on all the time, or turn it off when it is not in use?

Compelling arguments have been made on both sides. I ll try to sum up the important points on either side, and I ll even give you my recommendation, but ultimately, it s up to you.

LEAVE IT ON:

Constantly warming up and cooling down is bad for electronic equipment, and the computer experiences some mechanical wear and tear every time you turn it on and off.

There s also the issue of convenience. It s much easier to plop down and go to work when you want to, rather than having to wait several minutes for the computer to turn on and boot up.

TURN IT OFF:

The hard drive may last longer. Since it is composed of moving parts, it stands to reason, the less they move, the longer it will last. This may not be much of an issue with newer computers. The hard drive will probably last longer than the useful life of the computer, regardless.

If the computer is on all the time, it will suck more dust through the ventilation vents. More dust = more heat = shorter life span for the computer, so it may be worthwhile to turn it off when not in use.

All computers can benefit from the occasional reboot, and turning them off allows this to happen. Over time, minor things go wrong and the computer doesn t bother to inform you; it tries to patch itself up and moves on. The cumulative affect of all these little hiccups can be to reduce performance or even cause the computer to freeze or crash. Turning the computer off now and then gives it a chance to reset itself and start fresh.

Turning the computer off when idle uses less electricity. Depending on your computer, it may use as much electricity as one or more 100 watt light bulbs. That can add up to quite a few dollars over the lifetime of the computer. Also, less electricity expended means less carbon emissions, which is better for the environment, reduces global warming, etc. etc. etc.

ON THE SUBJECT OF ELECTRICITY: While we re talking about electricity, there are settings on all computers that we can adjust to save power right now.

If you have a PC running XP, right-click on the desktop, and choose properties" from the menu that pops up. This will open a little window titled Display Properties" with several tabs underneath. Click on the Screen Saver" tab. On the bottom of this tab is a section titled Monitor power" with a button labeled Power..." - click on this button to bring up a window titled Power Options Properties."

On a Mac running OSX, choose System Preferences..." from the Apple menu, then click on Energy Saver."

Computers running different systems will have slightly different menus and settings, but the main idea will be the same. Explaining all the different settings is beyond the scope of this article. Suffice to say, these settings let you control how long the computer can run unattended (with nothing going on) before different parts of the system are turned off, or put to sleep, to save electricity. There are separate settings for the monitor (screen), hard disk, and the system (the entire computer).

Depending on how you use your computer, you can experiment with the settings to complement the way you work. Don t be afraid to tinker. Nothing you change here will damage the computer. Of course, the more things you turn off, and the sooner you turn them off, the more energy you ll save.

MY RECOMMENDATIONS: These aren t Commandments; they re suggestions. Be flexible and tailor them to your needs. If you plan on using your computer in the next 8 hours, leave it on. If not, turn it off or put it to sleep. I leave mine on during the day, and turn it off overnight. My computer is set to go to sleep if I walk away for more than twenty minutes. This way, my computer benefits from the occasional reboot, and I can reduce my total energy use, even if it is only a little bit.

CPU Technology - part 10

Centrino

The first generation Centrino platform (codenamed "Montara") was announced in March 2003. The trio of systems that comprise Centrino focus on battery life and the integration of wireless LAN technology. Only systems that include all three components:

a Pentium-M processor
the Intel 855 chipset family
an Intel Pro/Wireless LAN adapter.

are allowed to use the Centrino brand.

The Intel Pentium-M processor - previously codenamed "Banias" - should not to be confused with the earlier Pentium 4-M. Manufactured on Intel's 0.13-micron process technology and with a die size of 100mm2, the new CPU combines some of the best features of earlier designs to produce a new microarchitecture capable of delivering high performance with reduced power consumption.

Like the Pentium III-M, the Pentium-M adopts the same design principal of performing more processor instructions per tick of the system clock. It does this without generating too much heat and can run at low voltages. In addition, it also supports the Pentium 4-M's quad-pumped 400MHz FSB and support for both SIMD and SIMD2 instructions to further boost performance. Since power consumption is directly proportional to clock speed, it is not surprising that a Pentium-M runs at lower clock than a Pentium 4-M, the new CPU being initially available is speeds from 1.3GHz to 1.6GHz. At the time of its launch, Intel claimed that a 1.6GHz Pentium-M offered comparable performance to a 2.4GHz Pentium 4-M at 50% less battery drain.

In addition to the new core, the processor's Level 1 cache has been increased to 32KB from the Pentium III-M's 16KB and the Level 2 cache is a full 1MB. However, to reduce power consumption when running on battery power, the chip only powers up the amount of L1 cache it actually needs - estimated by Intel to be 1/32 of the full cache size on average.

The new chip also introduces further refinements in Intel's established SpeedStep technology, which dynamically reduces processor speed and voltage as the situation allows. The Pentium-M's more compartmentalised processor allows finer control over shutting down the parts that aren't needed and reduces the voltage before the frequency slowly enough for the CPU to be able to continue what it's doing whilst this is happening.

Designed in tandem with the Pentium-M processor, the Intel 855 chipset has a lower core voltage in comparison to previous generations of memory controller hubs and utilises innovative design features to reduce memory interface power during system idle conditions. Design enhancements such as increased burst length size, timing improvements and shorter refresh cycles also contribute to improved performance.

The 855 chipset's features include:

a 400MHz (100MHz x four) system bus offers a peak bandwidth of 3.2GBps
DDR memory channels offering a peak bandwidth of 2.1GBps, and
an AGP 4x interface allowing graphics controllers access to main memory at over 1GBps.

and the new ICH4-M Southbridge offers standard support for:

Ultra ATA/100
10/100BaseTX Ethernet
AC97 audio
PC Card
Modem
USB 2.

The chipset comes in two forms, the 855PM and the 855GM, the latter including integrated graphics.

The third and final Centrino component is the Intel PRO/Wireless adapter. When details of Banias were first revealed in 2002, the expectation was for the wireless networking support to be hardwired into the motherboard as part of the chipset. In fact, Wi-Fi has been implemented as a mini-PCI card and slot. This is a more sensible arrangement, since it allows more scope for upgrades of a rapidly developing technology.

Indeed, it was not long before the benefit of the revised strategy were seen. With the work on wireless standards progressing more quickly than had been expected, Intel revised its plans for upgrading Centrino's original 802.11b part to accommodate other wireless standards. By mid-2003, the schedule was to have introduced a dual-band 802.11b/802.11a adapter by the third quarter and to have bundled support for 802.11g by the end of the year.

Also scheduled for the end of the year is for the Centrino processor manufacturing process to move from 0.13-micron to 0.09-micron. With the chip available in both FCPGA and FCBGA packages, these low voltage CPUs offer the prospect of high-powered, wireless-networked, ultra-portable notebooks in the not too distant future.

How to Remove Spyware Malware Adware & Boost PC Performance

Manual Spyware Removal
Sometimes you may know a definite program is spyware. In this case, you can try to remove it by hand. This is done by using the uninstall function of your computer. For Windows users, you can remove specific applications by going to your control panel (in "Settings") & selecting the "Add/Remove Programs" function. one time there, you will notice a list of programs. Click on the program you think to be spyware & pick "Remove". Make definite to restart your computer after
the removal to be definite all

Now that you know what spyware is, how it gets onto your computer, & the security issues it can generate, you very certainly need to remove this unsafe pest. you can do this in two ways: by hand, or by using an anti-spyware program

Unfortunately, most of the time removing spyware is not this simple. For example, how are you able to know for definite that a definite program is spyware? If you uninstall the program the spyware came with, it doesn't mean that the spyware will be uninstalled . Also, plenty of spyware programs are invisible, meaning that they won't show up in your program list. sometimes spyware programs can disguise themselves as programs important to your computer by using official sounding names like "winstartup". Spyware can also disguise itself by using dozens of different file names in different locations, or even by generating random names so it's not as basically detected. Even if a spyware program appears on your program list & you can uninstall it, not all traces of the program are always removed. In this case, you ought to make use of an anti-spyware program.

Changes necessary for the spyware to be removed are complete.

Spyware Removal Using an Anti-Spyware Program
The first rule of removing spyware by using a specialized program is to not rely on anti-virus programs. Because spyware is different from viruses, you need a different program to remove it. Check out our section on anti-spyware program reviews to pick one that's best for you.

Next, exit all browser windows & programs that you've walking. This includes electronic mail. you ought to also disconnect your computer from the web. These functions impede the functionality of the spyware remover because it can't scan files that are in use for spyware. The
more activity you've going on in your computer, the more likely it is that spyware is open & working .

Start by downloading the latest updates for the program you're using. This ensures the program is up to date on what spyware to look for & how to find it. Most spyware removers will have an "Update" button you can click on to download the latest information.

After the scan, turn on immunization options to help protect your computer against the spyware programs your scan has present in the future. Immunization options can be turned on by a button called "Immunize." Next permit your spyware cleaner to remove any spyware it finds.

One time everything is exited & you're disconnected from the web, run a scan using your spyware cleaner. Do this by pressing the "Scan" button. This means that your anti-spyware program will look for suspicious files on your computer & report back to you, & you will be
given a choice of what to do with any suspicious files it finds.

After you run a scan using your anti-spyware program for the first time, restart your computer & run a scan again. This ensures nothing was missed the first time. Let the program remove any additional spyware files. If suspicious files were present in the work of the second scan, restart your computer & run the spyware remover again. Keep repeating the scan-restart-scan process until your anti-spyware program cannot find any more spyware.

If you repeat this process one time & your spyware remover keeps finding spyware, or if your program can't find any more spyware but you think there's still some left, you may need to try walking a scan in your computer's "safe mode." When you start up your computer in "safe mode," only the most essential processes can activate. This will prevent spyware from activating in the background & trying to hide itself while your spyware remover scans for it.

When you've eventually removed all spyware your computer, you can start undoing any destroy or setting changes the spyware may have caused.

Remember, the prevention of spyware is the best method of keeping your computer safe. Learn about spyware prevention so you can protect your computer from spyware in the future & avoid going through the complicated removal process.

Other Options
sometimes spyware programs can become so embedded in your system that you can't deal with it yourself. For example, your computer may not be able to start up or open its web browser anymore. In these cases, you may need to contact a local computer technician who knows how to fix the issue.

Spyware Removal Complications
Because of the nature of the connection between spyware & freeware, namely that spyware producers pay freeware producers to include the spyware in their product, the removal of spyware may affect the freeware program it was installed with (if that's the way the spyware got onto your computer). Spyware is a kind of revenue to the company that produced the freeware, so if you remove the spyware sponsoring it, the freeware may no longer work. This is a tiny cost to pay to remove such a security threat from your computer, but removal is your choice, you must pick where your priorities lie.

You may not know for definite if a freeware program will stop working until you remove its spyware. But there is a way to check whether removing spyware will affect the performance of your freeware. Most spyware removers give you an option called "Quarantine." This means the spyware cleaner will disable spyware files & put them in a folder to be deleted later than deleting them permanently right away. this lets you run programs after the spyware quarantine & make definite everything still works with the suspicious files removed. you can then return in to your spyware cleaner & delete the suspicious files permanently. If something is not working properly with the spyware files quarantined, you can restore them. this lets you check the effects of spyware removal on your programs without actually removing it.

If you pick the quarantine option & everything on your computer appears to be working well after cleaning, keep in mind to return in to your anti-spyware program & delete the spyware files permanently.

It does need to be stressed that spyware can be a major threat to the security of your computer. If your pick the quarantine option & find that one of your freeware programs doesn't work properly with its spyware removed, think carefully before restoring the spyware. assess how important this program is to you & whether you can install another program without spyware that would work as well. Restoring the spyware ought to only be a last resort.

3D Monitors and Computer Displays

3D is no longer reserved to the movie theater, nor is it strictly the domain of broadcast television or kids movies on DVD or Blu-Ray. The newest frontier in 3D technology is destined to be the family computer as a new glut of 3D displays and 3D monitors are set to try to enhance the user experience in ways never before imagined but don't expect them to be as affordable as current cheap LCD monitors.

How Do 3D Monitors Work?
Most of the new 3D display technologies build on the current standard for 3D that people are used to seeing in the movie theater. In order to view the 3D images on the computer screen a user must wear a pair of polarized glasses. These are not the old style red and blue filtered glasses, but a newer version of 3D technology that uses a special kind of polarization to separate the images into two parts (one intended for each eye).

In the theater, most movie companies use circular polarization, a technique that allows the wearer of the glasses to tilt their heads at any angle (in case they want to rest their head on their significant other) but in the more fixed position world of computers the alternative of linear polarization is also being used.

Are Glasses Always Required To View 3D Computer Images?

For several years researchers have been tinkering with ways to produce 3D images without the need for glasses. Some manufacturers, such as Phillips Electronics, have already begun to demonstrate a new type of television monitor that produces 3D images without the need for glasses. It is surely only a matter of time before this technology trickles down into smaller computer monitors.

For those that cannot wait the Zalman TRIMON is a 22 inch LCD monitor that converts images and games into 3D using special software. The Zalman does require polarized glasses (provided) in order to view the monitor in 3D.

What Are The Current Drawbacks To 3D Displays and Monitors?
Aside from the relative scarcity of 3D monitors in the marketplace at this time the primary problem is the total lack of 3D enabled content. In order for a computer based video game to be played in true 3D requires not only a very specialized 3D monitor but also that the game itself be programmed to make use of that technology.

Many new 3D monitors such as the Viewsonic VX2265wm and the Samsung 2233RZ made a big splash at the 2009 Consumer Electronics Show and although they do a good job of converting existing games and applications into 3D, a true 3D experience will only happen once vendors write content specifically for viewing on 3D displays.

While many still consider 3D to be a fad that will never become a ubiquitous part of society, many in the electronics industry are betting on it, leaving a high likelyhood that 3D monitors and 3D displays will continue to grow in popularity.

ACi - Perfecta Review

Despite being relatively inexpensive, the ACi Perfecta is a nicely made machine. The major mouldings are decently thick and the body of the notebook has the dense, solid feel of quality. At 43mm, lid closed, it's also thinner than several of the others here and that helps it along aesthetically. It still has a plastic lid, but for 999 you can't have everything.

The core specification is fairly predictable; 1GHz Flip Chip Pentium III, 192MB of SDRAM and a 20GB hard disk, while the graphics memory is sequestered from the main system. The actual graphics chip is S3's Twister.

Both the 14.1-inch XGA TFT screen and the keyboard are of a good standard, the former pleasingly bright and the latter roomy and easy to get used to thanks to large keys and a fairly logical layout.

Probably on the basis of price, this model is equipped with a straight 8-speed DVD-ROM rather than a combo drive, and like the floppy drive it is fixed, not modular.

As with the Rock Sigma, also reviewed here, there's no serial port on this machine, although it does have a conventional parallel port as well as two USB ports. It also sports a FireWire interface and the obligatory modem, plus an integrated 10/100BaseTX LAN adapter.

Battery life was fairly good at about 2 hours 20 minutes under continuous use, which should mean that you can get a meaningful amount of work done before the shutters come down.

A one year collect and return warranty rounds the Perfecta off nicely, and left us with the feeling that it represented better than average value for money.

ACi - Perfecta price

999.00 + VAT

ACi: 020 8830 1958

www.aciplc.com

How to Fix Hard Drive Corruption using CheckDisk CHKDSK

Over time hard drive could create errors for lots of reasons. Causes like power outrage, power surges, improper shutdowns & age of drive are some of the most common reasons for errors in hard drives.

The specialists at computer services offer a technique that can repair a damaged hard drive. It is kind of a check & at the end of it you can be sure if the hard drive is nearing its end. It is not a difficult check. you can do it yourself. & if you have any kind of difficulty jogging it you can contact any time to our 24/7 computer support specialists. You require to narrate your computer system & they will advise you what you will require to do in the situation. If you're not a computer geek you can easily get the help of remote network support team on a nominal charge.

The tech support specialists desires the users to have a back up of the systems & all the important information before jogging the check because you can lose your invaluable information in the work of the jogging of the system depending on the extent of the damaged caused to the hard drive.

The specialists at computer services team require you the insert a Windows XP/2000 installation compact disc & restart the computer. you can get the prompt asking for the boot technique. you can get another prompt asking what you would like to do? Then you require to pick the letter "R" to enter the Windows Recovery Console.

You will get the prompt about what partition you would like to boot to & you will select the partition that has the Operating Systems installed in it. May be you will require to give an administrator password or may be you will require to enter basically by pressing enter button.

Another prompt will appear asking for command. You will require to type the command chkdsk /p & then you require the press enter on your keyboard.

But if one or more errors are found you can type the command chkdsk /r & press the enter button on your keyboard. Once you have pressed the enter button the CHKDSK will start checking for any errors in every sectors & will automatically repair them. The methods can take time depending on the size of the drive.

Now it is the time for checking the errors of your drive. The check will be run to check the errors. If you get any message like this "One or more errors detected on the volume", your hard drive errors then can be fixed by using CHKDSK. But if you don't get any of such messages then CHKDSK won't be able to fix the errors on your drive. Then may be you will require to consult the computer services professional team.

Once the scanning for the testing job is done, & it returns to the command prompt you can type the command chkdsk /p & can press the button enter on your keyboard.

If you see no error in your drive you have successfully done your testing technique & your hard drive is repaired. If you see the errors again this means that the CHKDSK was unable t repair the damage.

Now you can exit the Recovery Console & can remove the compact disc of Windows XP/2000 installation.

How to Update Your System BIOS - part 2

Identifying your BIOS chip

Your BIOS will most likely be stored in a 32-pin chip, which can typically be identified by a silver or gold sticker that shows the name of the BIOS company - such as AMIBIOS, AWARD or Phoenix - and a code that indicates the version of code it contains.

If it's rectangular in shape, it's what is known as a DIP (Dual In-line Package) chip. Older motherboards may have 28-pin DIP BIOS chips.

If your BIOS chip is square with connections on all four sides, it is in a PLCC (Plastic Leaded Chip Carrier) package. A locating notch indicates the orientation of pin 1.

Socketed PLCC chips are a little more tricky to remove than DIP chips and are best tackled using a specially designed removal tool.

If you have a DIP or PLCC chip that's actually soldered to your motherboard, you're out of luck - updating your BIOS is not an option!

Replacing your BIOS chip

Modern-day motherboards have EEPROM BIOS chips that can be reprogrammed by software. These are also referred to as flash PROM or flash ROM, the process by which they're updated being known as flashing.

If your BIOS isn't flashable it's still possible to update it - provided it's housed in a socketed DIP or PLCC chip. This involves physically removing the existing chip and either replacing it after its been reprogrammed with the later version of BIOS code or exchanging it for a completely new chip. Motherboard manufacturers generally provide a BIOS upgrade service for a limited period after a particular model of motherboard comes to market. During this period they should be able to provide you with a patched BIOS containing the latest enhancements and "bug fixes".

The replacement option may also appeal to some who actually have flashable BIOSes ......... but also have a nervous disposition! Notwithstanding the efforts motherboard manufacturers have made in recent years to simplify the process, the fact remains since flashing overwrites your existing BIOS, it has the potential of rendering your PC unusable should anything go wrong during the process or should you inadvertently use an incorrect BIOS file.

For older motherboards there are a number of companies that provide a specialist BIOS chip replacement service. Some require that you send them your BIOS chip for reprogramming, others will simply send you a new chip provided you can provide them with the necessary detailed information on your motherboard and existing BIOS chip.

Proper identification of the latter will generally require that you peel off all stickers on top of the chip to reveal the information printed directly on the chip itself.

A DIP chip can be removed using a small flat blade screwdriver or pocket knife. Insert the blade under one end of the chip and gently lever it until it begins to lift from the socket. Be careful to keep the angle to which it's raised shallow or you'll risk bending the legs of the chip. Move to the other end of the chip and lever it to the same level and then some. Repeat the process until the chip is completely released from the socket.
Removing a PLCC chip is a little more tricky, and it's possible to get a special extraction tool designed for the purpose. However, a with care a similar method to that described for a DIP chip will work, especially if you use a very small jeweller's flat blade screwdriver.
If you're reinstalling the same reprogrammed chip or a replacement chip, first make sure that all the chip's legs are straight and perfectly in line. Orient the notched end of the chip so that it aligns with the notch in the socket. Make sure all of the chip's legs are lined up with their corresponding socket positions and gently push down on the top of the chip until its legs begin to slide into in the socket. Be careful to confirm that all legs are properly located before applying stronger pressure to fully seat the chip in its socket.

People often confuse CMOS RAM with their BIOS, thinking of them as one and the same; in fact they're completely separate components.

The former is a block of memory made from very low power consumption CMOS (complementary metal oxide silicon) RAM chips, which is kept "alive" by a battery even when the PC's power is off. It's used to store basic information about the PC's configuration: number and type of hard and floppy drives, how much memory, what kind and so on. The other important data kept in CMOS memory is the time and date, which is updated by a Real Time Clock (RTC), the clock, CMOS RAM and battery all typically being integrated into a single chip.

All this used to be entered manually, but these days auto-configuring BIOSes copy the manufacturer default factory settings from the BIOS chip to the CMOS RAM, where they can be subsequently customised via the BIOS Setup interface. These factory default settings can be reinstated, either by discharging the CMOS RAM by jumpering a motherboard pin header or by invoking the Load BIOS Setup Defaults option from Setup.

IRAM A New Pattern in Memory

Posing from a new era of computing concepts, consumers are overwhelmed with choices on computer architectures

. The underlining idea of performance is rapidly changing, creating gaps in efficient design. Personal connectivity has become a constant factor of daily routines, and commerce has split into multiple playing fields forming a wireless race to an undefined venue. It is true that multi-tasking is no longer tied down to our personal or office pc s but to pocket size mobile devices that stream audio and video to our delight. Consumed by multiple choices we typically do not know the reality behind the constraints of devolving such computing devices and architectures. The goal of this paper is not only to open the eyes of the typical consumer, but to inform them of the complex constraints and issues faced by current computing demands. Concerned mostly with mobile computing architecture, we will examine the current concept of Intelligent RAM or IRAM for short, witch offers a new concept of chip-design for energy efficiency and performance.

In achieving a full understanding for the need of the new creative architectures of microprocessors, we must first fully understand different kinds of computers and there every day usage. In example, one would not own a bus pass and drive a car to work every day, similarly one would not buy a server to use as a personal computer. By understanding the different needs of the consumer and looking at the current types of computing, a prediction of the need for future computer designs can be determined. By observing the modern devises out today we can see that there are many types of computing needs.

Desktop

From the original personal computer to the high performance machines found in most homes today, personal computers are used for every day routines. Checking your email, online commerce, paying bills, to righting research papers like this one. It s clear that we as the customers expect our home machine to be able to do a number of different tasks. But do we need to have the fasted machine, and what makes a machine fast? For desktop applications the use of the billion-transistor chip is not always necessary. Multi-tasking and graphic performance is more the concern than floating point performance. Meaning that the average desktop user doesn t need to be able to do an extreme amount of floating point operations at one time, leaving the multi-threaded architectures in the lead for this type of computer. These chips deliver the best performance do to there advance out-of-order and advanced prediction techniques.

Server

Online commerce has become a complex multi-user processing, or parallels processing. A severer has to be able to hand a number of floating point operations at one time. For this task the use of processors with parallism and high memory bandwidth.

When we look at computer architecture we want performance based on user environment. But when you get down to it the chip must be able to use the software that is not extremely complex. In reality simplicity built on simplicity is the goal of good design.

Mobile devices

Mobile devises have evolved in the past 15 years, taking multiple devices that perform a single task to a devise that perform multiple tasks. Modern cell phones now have operating systems that have, video, imaging, sound, speech recognition, gaming, store large amount data, and perform arithmetic operations. As each year passes the advances of mobile devises improve. What do we really demand out of a mobile device? It is from this question that we can determine constants that haven t changed since the creation of mobile devices size, battery life, and performance. Size must be small, battery life must be the same or out perform the previous, and performance must improve as with the different applications in one device.

The demand to constantly network is becoming an increasing demand. Every day routines are becoming easier due to the constant demand to be able to perform computing tasks anywhere. These routines our not just for communication but for commerce as well. The idea that faster is better is changing to connectivity and multi-tasking on demand is optimal. Using this reasoning computer architects are rethinking the modern chip design. A chip design for a desktop and a server is mainly concerned on processing large amounts of data at the same time. But in reality this in not necessary for mobile devices since real time connectivity is not large but small and fast. The typical real-time video would only be 8 to 16 bits long per pixel and would only need to be processed and displayed to the screen. Compared to desktop and server environment, that has 32 to 64 bits of information that is processed and stored to memory. Leading to the question again of performance, this question is taking on two different answers. Each answer is pending on the type of computing. For mobile computing real-time process is more of an issue of reliability. The ability to have Coarse-grained parallelism and small data cashes is the goal, forcing chip architecture to be redesigned. The demand for increasing bandwidth is in direct conflict with the battery size and life.

Wireless devises must perform all operations with little than a 2 watt budget, compared to most high-performance processors with a budget of tens of watts. This creates a demand for two things, more powerful small batteries, as well as a processor that consumes very little power. Battery development has come a far way in the past but it is not cheap. Neither is the development of a chip that consumes hardly any power. In the near future it will be a combination of a cost efficient battery, with a powerful low powered processor. To fully under stand the effects of implementing a lower powered processor with out having to give up functionality. We must take into effect the size of the memory on the devise and the size of the executable able to run on the chip. Typically the higher number of tasks available on a devise the larger the software package is. Larger software means larger memory, bringing the issue of complexity into play. If the complexity on a chip is large, the executable file will be as well.

From the different types of computing devices the demand for a chip that compromises in multiple ways is growing. Performance should not be based on cashes bandwidth, size, or processor speed, but on bandwidth between the memory and the processor. Since your machine is only as fast as the bus between the processor and the memory. The right solution would be to decrease the distance between them as much as possible. The closer the distance, the more region of the chip will be accessible in a single clock cycle. Another concern is time needed to communicate an operation. Since most designs for billion-transistor chips spend a great deal of time on multiple cycles "communication among multiple cores or tiles." Taking all concerns in hand IEEE purposed a new type of chip design call the VECTOR IRAM.

VECTOR IRAM

Imagine a chip that combines memory and logic. This would not only provide a solution to communication speed but to power consumption.

"The vector IRAM processor consists of an in-order, dual-issue superscalar processor with first-level caches, tightly integrated with a vector execution unit that contains eight pipelines. Each pipeline can support parallel operations on multiple media types and DSP functions. The memory system consists of 96 Mbytes of DRAM used as main memory. It is organized in a hierarchical fashion with 16 banks and eight sub-banks per bank, connected to the scalar and vector unit through a crossbar. This memory system provides sufficient sequential and random bandwidth even for demanding applications."

The base of this processor is the vector design. Vector compilers are not as useful for performing large integer processes but are very competitive with floating point operations as well as graphic performance. For years there have been many compliers that are vector based in the commercial environment. Using the vector design will keep the complexity for increasing allowing module design. The main concern for the designers is the cost of implementing and testing the IRAM, since the combination of memory and logic. To fully understand the combination of memory and logic on one chip we must look into the type of memory used (DRAM) how it is produced and the most cost efficient way of implementing it on the chip.

DRAM

Producing chips and memory have been two separate things in till now. The productions of both items involve many factors and tests. Hence combining the two would not provide a short term cost effective chip since the testing of the memory and the logic would have to be done, e.g. redundant logic testing. But this is the price that must be paid to develop a chip of this type. A few more disadvantages are that the amount of memory on the chip might not be enough to store an application meaning that the chip must access conventional memory, defining the purpose of the chip. Drams refresh rate increases pending operating temperature. If we were to bypass the idea of these constraints and just focus on the future, we would have to wonder the effects of the IRAM on commerce.

Since the IRAM is considered a microprocessor it will be competing with companies that have been in the microprocessor market for years. Even more freighting is that the main producers of the IRAM will be memory companies that do not have any experience in that market. The memory market does not have the concern of software. On the production scale the microprocessors made a year are not even close to the billion of DRAMS, the key is finding a design that exploits the memory bandwidth potential of IRAM while leveraging software developed for traditional computing."

Implementing parallelism into the instruction set architecture decreases the size of the software that is implemented, as well as spending less wattage on high clock speed. Numerous testing was done on IRAM and many of its competitors for performance under different benchmarks. Among these benchmarks were SPMV (complex matrixes), Histogram (histogram performance for an pixels in a 500x500 image with a base 2 depth), Mesh Adaptation (a mesh with very large triangular, vertices, edges). The overall performance of the IRAM won over its competitors, not only in performance but in using less watts/mops.

As covered above in the mobile devise section, the demand for this type of computing is vastly increasing. Adaptation of low energy consumption memory is not only the goal but near reality. Today s microprocessors tend to be energy hogs in memory loads and stores. IRAM provides a simple solution to this with placing memory and a microprocessor on a single die, eliminating the need for large on-chip cache-based memory. The architecture implements DRAM memory instead of traditional SRAM memory, this is due to the high density of DRAM allowing more on-chip memory. The goal of IRAM architecture is to cut down external memory accesses to a bare minimum.

This goal gets its motivation from the fact that the performance rate of processors increases at a rate of over 6 times faster than memory per year due to slow off-chip buses, also due to the vast increase in energy efficiency of single chip processors with large on-chip memory.

Today there are many high performance machines that run below there peak arithmetic performance do to lack of memory bandwidth. The IRAM architecture provides a solution to this problem with the combination of DRAM and the microprocessor in a single chip. In fact the peak memory bandwidth for the IRAM is 6.4 GB per second, witch is 5-10 times higher than most machines. Due to its explicit parallelism in vector instructions higher arithmetic performance is achieved.

The IRAM chip uses the MIPS architecture having 32 64-bit vector registers, each register can be subdivided to operate on 8, 16, 32, and 64-bit data types. By allowing the subdivision of registers the number of elements stored can be greatly increased, thus increasing arithmetic performance.

Address generation is very important for any microprocessor. Memory addresses have to be checked for validation and collision before being processed. The IRAM architecture allows for 4 64-bits lanes per clock cycle, only having 4 lanes limits the performance. Performance is increased at 4 32-bits lanes out performing Pentium 4 chips, but peak performance reached at this level.

There are many ways of implementing memory and processors, first is the traditional way, placing large and expensive SRAM memory with a CPU in a logic process. Second is the IRAM architecture by placing CUP logic with memory. The second choice is the optimal choice in energy and cost. By eliminating DRAM on-chip we can eliminate the need for second-level on-chip caches. First level-caches are desirable for performance. By leaving a small on-chip cache and implementing a DRAM array we can assume that mostly all memory tasks can be performed on-chip with out external memory accesses.

The IRAM project promises many great achievements that will provide simple solutions to on going demand for performance networking. Implementing these ideas as you can see is the first stage, and producing the finished product in a cost effective way is the second. One thing is a fact the new and creative design idea of combining memory and a microprocessor on a singe chip is truly not go away. Personal connectivity has become a constant factor of daily routines, and commerce has split into multiple playing fields forming a wireless race to an undefined venue. This venue will shape the future of computer architectures.

Asus - L3C Review

The Mobile version of Intel's Pentium 4 chip hasn't been around for long, but Asus has already packaged it into this 1.7GHz notebook. That's not as high a clock speed as the desktop Pentium 4 found in some notebooks, but the theory is that the Mobile chip should better match the rest of the notebook's components, giving good performance and also good battery life. The other important factor, one that's readily seen from the Asus L3C's dimensions (326 x 267 x 40mm), is that the Pentium 4 Mobile chip consumes considerably less space than its desktop counterparts, although this machine does still weigh just over 3kg.

Styling-wise this machine isn't anything special, but it's not too over-the-top and quite discreet. Most of the casing is made from plastic, but it's thick enough to survive a few knocks and drops and there's sufficient screen support to prevent any serious flexing. The 1400 x 1050 pixel resolution LCD display, which is 15.1 inches in size, is sharp and bright and gives plenty of work space. This screen is powered by the ATI Mobility Radeon 7500 in 32MB guise and there's the option of sending the display output to either the VGA D-Sub port at the rear or the S-video port, i.e. to an external monitor or television set respectively.

Aside from the 30GB hard drive, there's also a floppy drive and an 8-speed DVD-ROM drive. The latter is modular and can be swapped with other factory options, such as a CD-RW drive or a combo CD-RW/DVD-ROM drive. The floppy drive is integrated into the left-hand side of the case and cannot be swapped. The notebook has 256MB of DDR memory, which can be upgraded to a maximum of 1GB via SODIMM sockets in the base of the unit.

The Asus L3C has both a 56Kbps modem and a 10/100Mbps network adapter built in and there's also a brace of IEEE 1394 (FireWire) ports provided for digital video editing or the connection of external hard drives and other high-bandwidth peripherals. There's also the usual audio and USB connectivity. An 802.11b wireless network adapter is available as an optional extra, as is a Bluetooth module and GPRS modem. The notebook has a full-featured keyboard and trackpad mouse with extra scroll buttons, and comes with Windows XP installed.

This machine is best used as a desktop replacement; quite apart from its power, the cooling fans push out warm air underneath the machine, so the space provided by the raised rear feet is essential to allow the internal components to be properly cooled.

Asus - L3C features - Verdict

The Asus L3C is a fast machine with pretty good battery life given its power - about two and a quarter hours - and a comprehensive range of features. The screen, storage, keyboard and general design are all good. One of the first Mobile Pentium 4 notebooks to be launched in the UK, the Asus L3C is a worthy desktop replacement notebook.

Asus - L3C price

1,850 + VAT

Asustek: +886 2 2894 3447

www.asus.com.tw

Diamond - Rio 500 Review

'MP3' is now claimed to be more often searched for than 'sex' on the Internet and the current fad for digital music shows no signs of reaching a peak. One of the main players (literally) in the MP3 boom is Diamond Multimedia's Rio device and the latest version, the Rio 500, is better than its predecessors in most respects. Slightly smaller than a typical packet of cigarettes, the Rio 500 is light and easily carried in the supplied pouch, clipped to your belt. It needs only one AA battery, which lasts for up to 13 hours of playback, so is very light and convenient. The device is available in silver or translucent teal or purple.

The Rio 500 has a back-lit LCD display which shows the track name, artist and other information. You can adjust the volume and use the built-in equaliser to set the device for different music types. Four buttons on the front face work like tape transport buttons for starting, stopping and track selection. A socket at the side takes the supplied lead to connect to any USB port on your PC or Mac - there's no traditional serial connection.

64MB of flash memory is built in, which is enough for around 16, four minute music tracks or up to three hours of pre-recorded speech. There are growing libraries of talking books available from Net sites like audible.com and Diamond's own rioport.com, much of which free. Add that to the ten of thousands of music tracks available from MP3 sites and there's no shortage of material to listen to.

The effectiveness of any MP3 player depends on the ease with which you can download sounds. In Diamond's case this is pretty straightforward, and the supplied Audio Manager is all-embracing. The same application handles recording of CD tracks, browsing the Internet for MP3 files, compiling a database on your hard drive and downloading to your Rio 500. It does all this in a fairly self-explanatory way... which is just as well.

Where the software is well designed, the accompanying documentation is poor. A couple of pages of text is all you get, mainly devoted to the PC and Mac software. There's little about the workings of the player itself and some aspects, like the need for folders in the Rio's file structure, are given no explanation at all. It would only take a little extra effort to provide all the necessary details, so why couldn't Diamond manage it?

This niggle aside, the Rio 500 works extremely well, but as with all MP3 players, you have to be quite dedicated to reload it each night with new sounds for the following day. What we need is a Rio with a gigabyte or more of internal storage. That may not be long in coming.

Diamond - Rio 500 features - Verdict

With double the internal memory of the Rio 300, and room for an extra 32MB in a SmartMedia card, the Rio 500 is easy to use and very convenient. Music playback is clear, if a little bass-light, and overall Diamond's device shows the way for music on the move.

Diamond - Rio 500 price

210 inc. VAT

Diamond: 01189 444400

www.diamondmm.com

Hard Drive Failure / Unreadable Disk

Symptoms of hardware failure or system file corruption may include:

Your computer won t boot

You receive error messages such as "Hard disk drive failure", "Hard drive disk not found", "Boot disk not found"

A secondary drive won t show up or allow you to see files

Here s what to do:

Backup data if possible.

If you ve recently installed software or made system changes, perform a system rollback (if Windows will boot).

Perform Check Disk (Chkdsk) from the recovery console.

Check the BIOS to be sure it detects the drive.

Check all connections and verify no pins are loose or bent. If possible, replace the power source and cable to verify that s not the problem.

Run diagnostics as included with your system. If none are provided, check your hard drive manufacturer s website.

A USB adapter kit will allow you to plug in the drive via USB, or you can install it on another system as a slave. Try to perform any of the above steps.

If it s your C drive, reinstall Windows.

If it still out of service, you have to make a decision:

If your data is not that important, you can reformat. At this point, you should be sure to keep a backup of all files as this drive may be dying.

If your data is valuable, you can pursue data recovery. There is software available on the internet, or if the problem is severe, you can consult an expert; they can provide an estimate in advance so you can decide whether to spend the money.

IBM - ThinkPad A20m Review

IBM has recently rebranded its ThinkPad range of notebooks into two broad categories, with an A or a T prefix distinguishing between them. A-series machines are considered desktop alternatives, while the T-series is aimed at users wanting more portable, lightweight computing on the move.

The A20m isn't at the top of the new range, but it's still fairly potent, with a 700MHz Pentium III SpeedStep processor cracking the whip over the show, although the standard 64MB helping of SDRAM is typically on the thin side, but this is true of virtually all corporate notebooks.

The removable hard disk is one of IBM's own Travelstar series, and gives you a healthy 12GB to play with, but it's possible that some buyers will want to opt for DVD or CD-RW rather than the 24-speed LG CD-ROM supplied as standard with this model. The CD-ROM drive is removable, so exchanging it for other drives will be simple and quick, and the list of available options goes on to include LS-120, a second battery pack or a second hard disk. System expansion is provided by the usual pair of PC Card slots, but the ThinkPad is fitted with a miniPCI combo card providing both V.90 modem and 10/100 Ethernet functions, so the slots might not see that much use.

Despite its 3-spindle design and reasonably solid construction, the ThinkPad isn't overly heavy, tipping the scales at a reasonable 3.05kg. This makes it a feasible candidate for the traveller who wants more power and better ergonomics than those offered by a typical sub-notebook for example.

The keyboard is up to IBM's normal high standard, with a spacious, logical layout quite similar to that of a conventional keyboard. The relative sizes of the keys are also preserved, which makes typing that bit easier and faster, and overall the ThinkPad is much easier and more pleasant to use than many notebooks.

The screen is a normal 14-inch XGA resolution TFT panel, but it's brightly lit by its sidelights and more legible in sunnier conditions as a result. If you are working in a dark environment, there's a tiny light just under the top edge of the screen which shines down onto the keyboard to help you see what you are doing, which is a nice touch.

Performance is fine, although as ever, we'd suggest adding at least another 64MB of memory to get the best out of the machine, and battery life proved to be a reasonable 2 hours 50 minutes under light but continuous use.

IBM - ThinkPad A20m features - Verdict

The new ThinkPad is fairly powerful, pleasant to use, modular and well made, and after dealer discounting it shouldn't be too expensive for a brand name corporate notebook either.

IBM - ThinkPad A20m price

1,895 + VAT

IBM: 0870 010 2512

www.pc.ibm.com/uk/

Step by Step instructions on how to remove viruses, spyware, and

Slow computer, and/or slow web connection.
unusual pop-ups or web browser redirections (beyond those expected
from dodgy websites).
Program failure, or inexplicable errors (even after a fresh install).
System functions unavailable (eg: Control Panel, Task Manager, web Explorer).
System giving a "RPC error", giving a window with a 30 second
countdown to a restart.
Excessive web cap usage, i.e high web traffic on your computer.

1. Run your virus-scanner, but beware, lots of modern viruses can circumvent (or hide from) anti-virus programs. Quarantine anything suspicious.

in case you do not have or your antivirus has expired uninstall first and download avg free

Tips

Warnings

If these steps are difficult to follow or impossible to achieve, call a computer service professional. Booting in Safe Mode is important if the malware is difficult to
remove normally. If this technique fails to clean your computer, download HijackThis,
run and save a log, and then post the log to a reputable security
forum such as BleepingComputer or GeekstoGo.

CPU Technology - part 12

Centrino Duo

In January 2006, Intel introduced the revolutionary Intel Centrino Duo Mobile Technology platform (formerly codenamed "Napa"), the third generation of the company's Centrino mobile processor technology bundle. Facilitating a whole new generation of thin and light notebook PCs, the following three next generation components will together enable future Centrino Duo laptops to surpass both the performance and battery life of previous generation Centrino platforms:

Intel Core Duo Processor
Mobile Intel 945 Express Chipset Family
Intel PRO/Wireless 3945ABG Network Connection.

The Intel Core Duo processor (previously codenamed "Yonah") is Intel's first mobile dual-core processor built on the company's next generation 65nm process technology. This has enabled a pair of Yonah cores to be fit onto a die only slightly larger than the previous Dothan-cored Pentium M (90mm2 compared to 84mm2 for the older part). The relatively small increase in die size and total transistor count (up around 11 million to approaching 152 million) is largely explained by the fact that most of the area of the die is taken up by the same 2MB of Level 2 cache.

In addition to the new mobile dual-core architecture, the Intel Core Processor includes several innovative features. These include a number of changes which together eliminate limitations that have restricted the Pentium M's multimedia performance relative to that of NetBurst architecture-based chips. Referred to a Digital Media Boost, these include instruction optimisations and performance enhancements for existing Streaming SIMD Extensions 2 (SSE2), 13 new Streaming SIMD Extensions 3 (SSE3) instructions and enhancements to floating point instruction decoding performance that will allow multiple SSE instructions to be handled in parallel.

Another new feature is a shared 2MB L2 cache which enables an active execution core to access the full 2MB cache when the other execution core is idle. Dubbed Smart Cache, this uses dynamic cache allocation across both cores to enhance performance and reduce cache under-utilisation and misses. Efficient data sharing between both cores minimises FSB traffic and reduces cache coherency complexity and the processor's enhanced Data Pre-fetch Logic speculatively fetches data to the L2 cache before cache requests occur, thereby reducing bus cycle penalties.

In the past the design of mobile processing platforms have required a trade off between performance and battery life. In the case of the Core Duo, the design goal was breakthrough performance while at the same time optimising energy efficiency and enabling longer battery life. The result is that each of the CPU's execution cores is able to independently and dynamically transition to Halt, Stop Clock, and Deep Sleep low-power states, so that if only one core is being utilised, the second core can still enter an idle state to help save power. Moreover, Dynamic Power Co-ordination also enables co-ordinated transitions to Deeper Sleep and an Enhanced Deeper Sleep mode, for example when the Smart Cache dynamically flushes the cache to system memory during periods of inactivity.

The Mobile Intel 945 Express Chipset Family is the next generation Intel Hub Architecture for notebook PCs using Intel Centrino Duo Mobile Technology. As with previous Centrino chipsets, there are three variants: the 945PM is the plain mobile chipset, the 945GM adds integrated graphics and the 945GMS is the ultra-low voltage chipset with integrated graphics.

The features of the 945PM chipset include:

Features	Benefits
667 MHz Front Side Bus	Supports Intel Core Duo and Intel Core Solo processors with up to 25% faster data transfer rate compared to the previous generation bus speed.
PCI Express* x16 Interface	Delivers greater than 3.5 times the bandwidth over the traditional AGP interface and supports the latest high-performance graphics cards.
PCI Express* x1 Interface	Offers up to 3.5 times the bandwidth over traditional PCI architecture, delivering faster access to peripheral devices and networking.
Intel High Definition (HD) Audio	Integrated audio support enables premium sound and delivers advanced features such as multiple audio streams and jack re-tasking.
Intel Matrix Storage Technology	Enables enhanced performance, power management and data protection for the storage subsystem.
Dual-channel DDR2 667MHz Memory Support	Up to 10.7 GBps of bandwidth and up to 4GB memory addressability, for faster system responsiveness.
Integrated high speed USB 2.0	Support for 8 USB 2.0 peripherals for maximum 40x faster data transfer and backward compatible to support USB 1.1 devices.

The 945GM and GMS variants' integrated graphics is provided by the new Graphics Media Accelerator 950 (GMA 950) graphics engine. Graphics require dedicated memory and processing, and applications have divergent memory needs. Some applications, such as e-mail and Internet browsing, require very little graphics memory. Others, such as games, require more. Intel GMA 950 graphics support both of these demand levels through a unique intelligent memory management scheme called Dynamic Video Memory Technology (DVMT). DVMT handles these diverse applications by providing the maximum availability of system memory for general computer usage, while supplying additional graphics memory when a 3D-intensive application requests it.

Intel GMA 950 also supports Dual Independent Display technology. When an optional adapter card is installed, this capability allows two separate displays to be connected to the system at the same time. One way to use this capability is to create a larger desktop work surface spanning multiple displays. Intel GMA 950 graphics also supports Media Expansion Cards, which enable dual TV tuning and digital display connectors such as DVI and TV-Out in a single card solution.

As with previous version of Centrino, the Centrino Duo platform specifies an Intel wireless card, in this case Intel PRO/Wireless 3945ABG Network Connection adapter. Compatible with all three commonly used wireless standards, 802.11a, 802.11b and 802.11g, this operates at 5 GHz or 2.4 GHz frequency at speeds of up to 54 Mbit/sec. Supporting enhanced features that make applications more aware, connected, and responsive, enabling mobile PCs to deliver a better on-the-go end-user experience, the 3945ABG is also available in a smaller PCIe mini-card form factor, facilitating lighter and thinner notebooks.

Access points usually serve bandwidth on a first-come, first-served basis. This presents problems for high bandwidth applications such as VoIP and media streaming. The 3945ABG provides a solution via version 10 of the Intel PROSet/Wireless software, which allows such applications to prioritise and reserve bandwidth using 802.11e QoS parameters. In addition, an intelligent access point selection feature allows load balancing of traffic across multiple access points, which helps increase overall bandwidth capacity, thereby potentially enhancing data, voice and video throughput.

Compaq - Armada E500 P3850 Review

The Armada E500 is Compaq's most powerful corporate notebook, following an update which now puts an 850MHz PIII SpeedStep in the driving seat. Being beefy, Compaq and corporate means a correspondingly inflated price, but let's face it, this is hardly unusual for brand-name corporate kit.

The look of the thing is stripped down, angular and faintly militaristic, which should appeal to the serious business user both for its conservatism and distant whiff of the battlefield. The build is good, with a solid, inflexible case body and a magnesium alloy lid to protect the screen, so it should stand up to a moderate amount of real world abuse without coming over all faint.

It weighs 3.45kg, which is noticeable if you have to cart it around for any distance, but if you are going any further than from the lift to the Merc, there's always luggage trolleys. The weight is partly accounted for by the fact that this is a three-spindle machine, so apart from the power supply, there's nothing else to add to the payload.

The 8-speed DVD-ROM drive and floppy drive supplied with the review sample are both removable, so you can tweak the specification without needing to open the case up. The options on offer include an LS-120 drive, plain CD-ROM, and a second battery pack if you need a longer running time.

You can also remove the 20GB IBM TravelStar hard disk quickly and easily, and there's a spare memory socket under the keyboard, so basic repairs and upgrades will be simple enough to carry out in-house if desired.

The same applies to the internal V.90 modem and 10/100Mbps Fast Ethernet adapter, which are combined on a MiniPCI card. This is vastly easier to remove and replace than many proprietary components, and of course there's a wider choice of available parts if you need to upgrade in the future.

The Armada has a nice, spacious keyboard which makes typing relatively straightforward, and Compaq has gone beyond the standard XGA screen and fitted this notebook with a 15-inch panel that runs in SXGA+, which is 1400 x 1050 in dots and lines. This means much more workspace to play with, and is another plus for the machine in general.

Used continuously, the Armada should keep going for up to 3.5 hours, which is reasonable for a powerful system like this, and performance was excellent thanks to a balanced configuration with no bottlenecks, which let the CPU do its stuff. Pricey, but impressive all the same, and with the Compaq name on the badge, this is likely to do well despite the cost.

Compaq - Armada E500 P3850 features - Verdict

This machine is probably not ideal for the typical private buyer or small business, but is likely to appeal to corporates looking for a seriously powerful notebook. Regrettably expensive, but very nicely done all the same.

Compaq - Armada E500 P3850 price

2,770 + VAT

Compaq: 0845 2704000

www.compaq.co.uk

Dual core computer processors: luxury or necessity?

Most of the talk going on in the computer processor industry is revolving around dual core processors. But what advantages do they actually give and is it worth it in terms of price?

All processors have a core. A processor also contains some memory, often referred to as cache, either L1, L2 or L3, depending on how close it is to the core, and the core itself, as well as a few other essentials. The core is the "brain" part, it performs all the big calculations that are needed for the various things a computer does.

Computer cores have been increasing in speed, and increasingly quickly. Manufacturers were in a race to have the chip with the fastest speed, measured in GHz. One surprise is that despite these increases in clock speed, the actual speed of programs didn't increase proportionately.

As modern programs make much heavier use of other computer parts like memory, and there are often many running at the same time, another approach was needed.

Dual core processors were the answer.

By putting two "brain" parts into the processor, you can run two programs on two cores, without having to share it between them. The effect of this is that when running two or more programs, the processor can now handle much more as a whole.

The part about them that might disappoint is gaming.

Unlike the multitasking environment that is usual for a computer either at home or at the office, games rely on the brute force of a powerful processor to help them along. So far there is no technology to take advantage of the two processors, like the ability to split its tasks over two cores. Most gaming has not improved with this new technology.

As with processors in the past the mainstream of dual core processors is dominated by the two big guys, Intel and AMD.

Intel offers two processors in its range, same processor, just different speeds. The lower priced of the Pentium D processors comes in at around $250. This price is reasonable considering how much you would pay for the top of the line single core processor.

The Pentium D is based on the same core as it's single core counterparts, just two of them inside. Its boost in performance is quite notable, and makes it presence felt in the multitasking environment.

The AMD Athlon X2 is AMD's offering in the dual core market. Unlike the Pentium D its lowest priced model comes in at a staggering $400. It's not expensive compared to processors like its FX series, which are over $1000, but in comparison to Intel it's expensive.

It too is based on the same core as its single core cousins and also offers the same performance increases.

The price of the AMD is surprising. From a company that became renowned for it's low cost, high performance processors this is quite a blow. Even the upper model of the Pentium Ds comes in at less that AMD's cheapest model.

The price might be justified if the AMD actually gave a significant performance boost, but it doesn't.

For the first time in a long time, I think I would be willing to switch back to an Intel processor. Although my preference is not for dual core, if I had or needed to switch I would certainly go straight for the Pentium D.

And finally, how do they compare to their now out of date traditional processors?

Considering how powerful processors have become I would still not make the switch. Dual core has not been around long enough to produce low cost, slightly out of date models. The power of the AMD Athlon 64 3000+ more than does it for my computing needs, and that's where I would stay for now.

So for those who are looking for the next cool thing for their desktop computer and price is not a huge issue, this would be your best choice, but go for the lower end Pentium D.

Interfaces - part 4

AGP

As fast and wide as the PCI bus was, there was one task that threatened to consume all its bandwidth: displaying graphics. Early in the era of the ISA bus, monitors were driven by simple Monochrome Display adapter (MDA) and Colour Graphics Array (CGA) cards. A CGA graphics display could show four colours (two bits of data) at 320 by 200 pixels screen resolution at 60Hz, which required 128,000 bits of data per screen, or just over 937 KBps. An XGA image at a 16-bit colour depth requires 1.5MB of data for every image, and at a vertical refresh rate of 75Hz, this amount of data is required 75 times each second. Thanks to modern graphics adapters, not all of this data has to be transferred across the expansion bus, but 3D imaging technology created new problems.

3D graphics have made it possible to model both fantastic and realistic worlds on-screen in enormous detail. Texture mapping and object hiding require huge amounts of data, and the graphics adapter needs to have fast access to this data to avoid the frame rate dropping and action appearing jerky. It was beginning to look as though the PCI peak bandwidth of 132 MBps was not up to the job.

Intel's solution was to develop the Accelerated Graphics Port (AGP) as a separate connector that operates off the processor bus. The AGP chipset acts as the intermediary between the processor and Level 2 cache contained in the Pentium II's Single Edge Contact Cartridge, the system memory, the graphics card and the PCI bus. This is called Quad Port acceleration.

AGP operates at the speed of the processor bus, now known as the frontside bus. At a clock rate of 66MHz this is double the PCI clock speed and means that the peak base throughput is 264 MBps.

For graphics cards specifically designed to support it, AGP allows data to be sent during both the up and down clock cycle, doubling the clock rate to 133MHz and peak transfer to 528 MBps. This is known as 2x. To improve the length of time that AGP can maintain this peak transfer, the bus supports pipelining, which is another improvement over PCI. A pipelining 2x graphics card will be able to sustain throughput at 80% of the peak. AGP also supports queuing of up to 32 commands via a process called Sideband Addressing (SBA), the commands being sent while data is being received. This allows the bus to sustain peak performance for 95% of the time, according to Intel.

AGP's four-fold bandwidth improvement and graphics-only nature ensures that large transfers of 3D graphics data don't slow up the action on screen; nor will graphics data transfers be interrupted by other PCI devices. Being primarily intended to boost 3D performance, AGP also provides other improvements that are specifically aimed at this function.

With its increased access speed to system memory over the PCI bus, AGP can use system memory as if it's actually on the graphics card. This is called Direct Memory Execute (DIME). A device called a Graphics Aperture Remapping Table (GART) handles the RAM addresses so that they can be distributed in small chunks throughout system memory rather than hijacking one large section, and presents them to a DIME-enabled graphics card as if they're part of on-board memory. The main use for DIME is to allow much larger textures to be used because the graphics card can have a much larger memory space in which to load the bitmaps used.

AGP was initially only available in Pentium II systems based on Intel's 440LX chipset. However, despite no Intel support (and therefore thanks to the efforts of other chipset manufacturers such as VIA), it had also found its way onto motherboards designed for Pentium-class processors by early 1998.

Intel's release of version 2.0 of the AGP specification, combined with the AGP Pro extensions to this specification, mark an attempt to have AGP taken seriously in the 3D graphics workstation market. AGP 2.0 defines a new 4x-transfer mode that allows four data transfers per clock cycle on the 66MHz AGP interface. This delivers a maximum theoretical bandwidth between the AGP device and system memory of 1.0 GBps. The new 4x mode has a much higher potential throughput than 100MHz SDRAM (800 MBps), so the full benefit wasn't seen until the implementation of 133MHz SDRAM and Direct Rambus DRAM (DRDRAM) in the second half of 1999. AGP 2.0 was supported by chipsets launched early in 1999 to provide support for Intel's Katmai processor.

AGP Pro is a physical specification aimed at satisfying the needs of high-end graphics card manufacturers, who are currently limited by the maximum electrical power that can be drawn by an AGP card (about 25W). AGP Pro caters for cards that draw up to 100W, and will use a slightly longer AGP slot that will also take current AGP cards.

Apple and Mac, is it For You?

Are you wondering what brand of computer to get? Why not try getting that one with an apple on. I m sure that all of us have seen that apple logo with a bite of its upper right side and I m also sure that all of us know who it belongs to. That famous apple is the logo of none other than Apple, Inc. This company is well known for its Macintosh personal computers, the iPod and the much talked about iPhone.

Macintosh, or popularly called as Mac, is a brand name for a group of personal computers produced by Apple, Inc. This also refers to the operating system used by these computers. Apple first introduced Macintosh computers in 1984 but suffered a decline when a cheaper and more efficient Microsoft Windows was introduced in the 1990 s. Since then more people started using Windows instead of Mac. But Apple fought back with the introduction of the iMac in 1998 and started to rise again soon after that. Today, Mac is still widely used by a great majority of people around the world and has given Windows a run for its money.

Apple has produced both desktop and laptops computers. Unlike the Windows operating system which can be used for any computer brand, the Mac operating system is only used with Apple computers. They have produced desktops computers with some of more common and latest models being the Mac Pro, iMac and Mac mini. They have also produced the MacBook Pro, Powerbook Powerbook Laptops and MacBook air for their portable computers.

The Mac Pro introduced in 2006 is a workstation desktop computer which uses Intel Xeon processors. The iMac introduced also in 2006 is a high-end desktop computer which is the first Macintosh with an Intel Core 2 Duo processor. The Mac mini introduced in 2005 is the smallest desktop computer to be released by Apple. This computer looks like a small box with a measurement of 6.5 by 6.5 by 2 inches. This also uses an Intel Core Solo or Intel Core Duo processor.

The MacBook Pro first introduced in 2006, is a 15 inch notebook pc with an aluminum casing. It uses Intel Core 2 Duo processors and has 4 GB of RAM. The MacBook also introduced in 2006 is a 13.3 inch notebook computer with a polycarbonate casing. It also uses Intel Core 2 Duo processors and has up to 4 GB of RAM. The MacBook Air introduced early this year is a 13.3 inch notebook computer which weighs only 1.36 kg and is 0.16 inches thick. This uses Intel Core 2 Duo processors and 2 GB of RAM.

Aside from these computers, Apple has also produced the iPod which is a digital media player and the iPhone which is a phone, an iPod and an internet device in one. The computers have the usual accessories but both the iPod and iPhone has accessories too. These accessories can serve to protect your iPod or iPod and enhance them too.

How to Upgrade PC Towers or Laptop Memory Ram

Computer memory, also known as Random Access Memory (RAM), is just like your short term memory in your brain. It stores everything you're currently working on & recently worked on. As you can see that makes it a essential part of your computer because it stores vital information that you're using & want access immediately. No matter what the information is, pictures, sounds or just text, in the event you get a good amount of memory your computer will load that
information much faster & store it better.

Lots of people want to do a RAM upgrade there selves, but always run into the issue of figuring out which sort of memory to buy & installing it. in the event you didn't already know, there's lots of different types of RAM available on the market, & you want to get the type that corresponds along with your motherboard. in the event you don't know what a motherboard is, it's the sizable circuit board
inside of your computer that connects everything together.

First, let's talk about the two main types of RAM that are in use
today, SDRAM & DDR. SDRAM stands for Synchronous Dynamic Random Access Memory, & is the most common among PC's today. Most likely your desktop computer uses this type of RAM. I use to have SDRAM, & I thought it was all right because it got the job completed. i've switched though to DDR RAM, which is replacing SDRAM. The speed of DDR RAM is six times that of SDRAM, so you can imagine the difference. If your motherboard currently only has SDRAM slots, then you've no choice but to get that type of RAM. in the event you want to change to DDR RAM, then you want to buy a whole new motherboard & install it. To find out what RAM your computer uses just look at the instruction manual that came with it, or if it is custom built, look at the motherboard's instruction manual.

For all you laptop computer & PDA owners out there, the type of RAM in your laptop computer or PDA is called SODIMM. available at the same memory store you buy your desktop computer RAM from, just a small more costly & harder to put in.

Now that you know the different types of RAM, you want to know where to buy it from & how to put in it. To buy it, I recommend your local computer store because there will be a person there to help you & they will make positive that you buy the correct RAM. Here's a tip to,
bring your computers instruction manual with you to the store & they
will definitely know the correct type of memory you want. in the event
you want to buy online, then NewEgg.com & TigerDirect.com are two
great online computer stores that will deliver your RAM into your mail
box. & last but not least, you want to put in your new RAM. think it or not this is the easy part. First shutdown & unplug everything from your
computer & then remove your computer's case cover, to gain access to the motherboard inside. one time you can clearly see the motherboard, locate your RAM. you should know what it looks like since you just bought some & you can look at that. When you find it, you will notice a latch connected to the slot that holds it on each finish. Push down both of the latches to unhook them, & then gently pull the RAM stick out. It ought to slide out with ease, but if it doesn't, then wiggle it a small bit while pulling.

After that you just want to insert your new RAM. First count how lots
of slots you've available for RAM & how lots of of them currently have
RAM in it. sometimes you will notice 2 slots occupied & 1 open, or all
six slots could be used. Either way, you want to insert your new RAM
into an open slot, or if all are used then remove the oldest & least
amount of RAM to clear a slot. Then gently insert your new RAM & pull the latches back up on both sides, securing your memory into place. After that just screw your case cover back on, hook your computer back up to everything & then power it back on. Your computer will automatically detect the new RAM & no further installation method is necessary.

Well that is about it, I hope i've helped you. Just keep in mind to
keep your computer tidy and maintain properly, & it will live a long
life.

Making the most of your disk space

This article covers various ways of making your hard disk run more efficiently. In particular, it details ways of saving space and ways of helping to keep your system in tiptop form!

With the complexities of the Windows operating system, it can seem that disk space just ups and disappears! Those of us old enough to remember our massive 20-megabyte hard disks find that today's two-gigabyte disks a bit limiting! Where does all this space go?

Well, a lot can disappear with temporary files files created whilst we use our applications. Normally, these are removed when the application finishes, but as we all know, it's not every time that a program ends normally! At these times, we can end up with all sorts of rubbish lying around. This can be detrimental to our systems in the following ways:

Temporary files take up much needed disk space
Applications can crash due to old temporary files lying around.
System crashes if the windows swap file gets corrupted due to unstable temporary files

There are other files that can also clutter up our systems which are safely removable.We shall deal with these latter on in the article. First, temporary files how to manage and maintain a better system.

Care should be taken when carrying out these procedures. You MUST follow the instructions carefully to avoid problems!

There are a couple of things we can do to make it easier to manage our systems from the threat of temporary files. These are:

Create a set place for the system to create temporary files, rather than having them created all over the hard disk.
Clear out the set place on a regular basis, especially after a system or application crash

Here's how:

Creating a Set Place for Temporary Files
To do this requires the creation of a directory (or folder if you prefer). Add two lines to a file called AUTOEXEC.BAT. Follow these steps to do this. (This can be done for Windows 3.x users too rather than Windows Explorer you would use the File Manager)

1) Launch Windows Explorer

2) Go to the root directory of your C: drive (so that you see Contents of C:\)

3) Click on the File menu and select New . . . Folder

4) When the folder is created call the folder TEMP

5) . You should now have a folder called TEMP in your root directory (that is C:\TEMP)

That's the creation of the folder. Now we need to change the AUTOEXEC.BAT file. This file controls how your system starts and will contain commands that your system uses in order to find files and to set what are called Environment Variables. Environment variables are values placed in memory when your machine is switched on that any program can use to find out about your system (its' working environment).

You probably have these for your sound card and programs can use these to detect your sound set up. This is how programs seem to know how your system is set up. One of the environment variables we can set up is to tell programs where to put temporary files. We are going to set this up so that all application temporary files are placed in the folder we have just created.

Now we are going to change the AUTOEXEC.BAT file so that this happens. Before you start, it's a good idea to take a copy of it (use Explorer and copy it to another directory/folder so that if things go wrong, you can copy your existing file back). The AUTOEXEC.BAT file also lives in the C:\ directory. To make the changes, carry out the following steps:

1) Launch Windows Explorer

2) Look in the C:\ directory and click the left mouse button once on AUTOEXEC.BAT so that it is highlighted

3) Click the right mouse button and select Edit from the popup menu that appears. DO NOT ATTEMPT TO OPEN IT!

4) Notepad will open the AUTOEXEC.BAT file ready for the changes we are going to make.

5) Place the mouse on the first line and press the RETURN key to insert a new, blank line

6) Type in the following two lines exactly as shown:

SET TMP=C:\TEMP

7) Save and Exit Notepad

8) Shut your system down and reboot. That's it!

Now, when an application creates temporary files, it will place them in the \TEMP directory we created. This makes it easy for us to find and delete old temporary files.

Deleting Old Temporary Files

This job is simple now! Just go the C:\TEMP folder and delete all the files and directories you find there! You should make sure, however, that you are not running any other windows application when you do this! After a serious system crash, it is advisable to reboot your PC after deleting the temporary files.

You may find that Windows cannot delete some of the files. Don't panic; this means those files are in use and can be safely ignored.

Other Disk Hogging Files

Near the beginning of this article, I mentioned about other files that can take up disk space that can be deleted. Some of these files (like help files) should only be deleted if you no longer need help in that area (like some of the beginner's Windows help files). If you are in any doubt, leave the files alone. Here is a list of file types that you can search for that may be deleted.

DO NOT do a massive, global delete of these files as some applications (especially shareware titles), may need certain text files like README.TXT.

*.tmp Temporary files can be deleted

*.bak Backup files depends on application

*.avi (In \WINDOWS) Video files Windows 95 comes with lots of beginner files that take up lots of disk space. Delete these if you no longer need them

*.txt Text files Often installed with programs. Once read they can often be deleted

*.hlp Be careful with this one but help files DO take up a lot of disk space. Only delete if you are positive you do not need them

*.me Often part of README.TXT or README.1ST type files

*.old Often found when programs install and change system settings these files can usually be removed

*.doc Careful! some programs use these for their read me files but so might your word processor!

By regularly keeping track of what goes onto your hard disk, you can ensure that your system does not become cluttered!

Next week's article looks at adding an additional hard disk to your system. Things you need to think about.

Elonex - Piranha Pro Review

Elonex's Piranha Pro weighs in at a reasonable 2kg on its own or 3.5kg when attached to the docking station which is supplied as standard. The notebook itself is only 3cm high and when attached to the docking station the whole unit is just over 7cm high.

It performs well - as it should, being powered by a 750MHz Intel Mobile Pentium III chip, backed up by 128MB of main memory. The single spindle in the chassis is used by the 20GB hard disk, while the docking station has the 24-speed CD-ROM and floppy drives installed.

The 13.3-inch TFT screen is clear and bright, and powered by the onboard 8MB ATI Rage Mobility chipset, and both network connectivity and modem are built into the Piranha Pro. Networking is controlled by an Intel-based 10/100Mbps NIC, while the modem is a 56Kbps LT Win modem.

The rear panel of the chassis contains all the usual I/O ports; serial and parallel ports, VGA and an IR port. A single PS/2 port, a single Type II PC-Card slot and a USB port are housed on the side of the chassis. Two audio ports for headphones and microphone are built into the front of the unit and there is a proprietary port for an external drive.

The system reviewed came with Window 2000 pre-installed, but without any software bundle. Microsoft Office 2000 is offered at extra cost.

One of the more powerful systems in this group, the Elonex Piranha Pro is a fast and well-equipped sub-notebook.

Elonex - Piranha Pro price

1,999 + VAT

Elonex: 020 84522444

www.elonex.co.uk

Memory - part 3

DRAM

DRAM chips are large, rectangular arrays of memory cells with support logic that is used for reading and writing data in the arrays, and refresh circuitry to maintain the integrity of stored data. Memory arrays are arranged in rows and columns of memory cells called wordlines and bitlines, respectively. Each memory cell has a unique location or address defined by the intersection of a row and a column.

DRAM is manufactured using a similar process to how processors are: a silicon substrate is etched with the patterns that make the transistors and capacitors (and support structures) that comprise each bit. It costs much less than a processor because it is a series of simple, repeated structures, so there isn't the complexity of making a single chip with several million individually-located transistors and DRAM is cheaper than SRAM and uses half as many transistors. Over the years, several different structures have been used to create the memory cells on a chip, and in today's technologies the support circuitry generally includes:

sense amplifiers to amplify the signal or charge detected on a memory cell
address logic to select rows and columns
Row Address Select (/RAS) and Column Address Select (/CAS) logic to latch and resolve the row and column addresses and to initiate and terminate read and write operations
read and write circuitry to store information in the memory's cells or read that which is stored there
internal counters or registers to keep track of the refresh sequence, or to initiate refresh cycles as needed
Output Enable logic to prevent data from appearing at the outputs unless specifically desired.

A transistor is effectively a switch which can control the flow of current - either on, or off. In DRAM, each transistor holds a single bit: if the transistor is "open", and the current can flow, that's a 1; if it's closed, it's a 0. A capacitor is used to hold the charge, but it soon escapes, losing the data. To overcome this problem, other circuitry refreshes the memory, reading the value before it disappears completely, and writing back a pristine version. This refreshing action is why the memory is called dynamic. The refresh speed is expressed in nanoseconds (ns) and it is this figure that represents the "speed" of the RAM. Most Pentium-based PCs use 60 or 70ns RAM.

The process of refreshing actually interrupts/slows down the accessing of the data but clever cache design minimises this. However, as processor speeds passed the 200MHz mark, no amount of cacheing could compensate for the inherent slowness of DRAM and other, faster memory technologies have largely superseded it.

The most difficult aspect of working with DRAM devices is resolving the timing requirements. DRAMs are generally asynchronous, responding to input signals whenever they occur. As long as the signals are applied in the proper sequence, with signal durations and delays between signals that meet the specified limits, the DRAM will work properly. These are few in number, comprising:

Row Address Select: The /RAS circuitry is used to latch the row address and to initiate the memory cycle. It is required at the beginning of every operation. /RAS is active low; that is, to enable /RAS, a transition from a high voltage to a low voltage level is required. The voltage must remain low until /RAS is no longer needed. During a complete memory cycle, there is a minimum amount of time that /RAS must be active, and a minimum amount of time that /RAS must be inactive, called the /RAS precharge time. /RAS may also be used to trigger a refresh cycle (/RAS Only Refresh, or ROR).
Column Address Select: /CAS is used to latch the column address and to initiate the read or write operation. /CAS may also be used to trigger a /CAS before /RAS refresh cycle. This refresh cycle requires /CAS to be active prior to /RAS and to remain active for a specified time. It is active low. The memory specification lists the minimum amount of time /CAS must remain active to initiate a read or write operation. For most memory operations, there is also a minimum amount of time that /CAS must be inactive, called the /CAS precharge time. (An ROR cycle does not require /CAS to be active.)
Address: The addresses are used to select a memory location on the chip. The address pins on a memory device are used for both row and column address selection (multiplexing). The number of addresses depends on the memory's size and organisation. The voltage level present at each address at the time that /RAS or /CAS goes active determines the row or column address, respectively, that is selected. To ensure that the row or column address selected is the one that was intended, set up and hold times with respect to the /RAS and /CAS transitions to a low level are specified in the DRAM timing specification.
Write Enable: The /WE signal is used to choose a read operation or a write operation. A low voltage level signifies that a write operation is desired; a high voltage level is used to choose a read operation. The operation to be performed is usually determined by the voltage level on /WE when /CAS goes low (Delayed Write is an exception). To ensure that the correct operation is selected, set up and hold times with respect to /CAS are specified in the DRAM timing specification.
Output Enable: During a read operation, this control signal is used to prevent data from appearing at the output until needed. When /OE is low, data appears at the data outputs as soon as it is available. /OE is ignored during a write operation. In many applications, the /OE pin is grounded and is not used to control the DRAM timing.
Data In or Out: The DQ pins (also called Input/Output pins or I/Os) on the memory device are used for input and output. During a write operation, a voltage (high=1, low=0) is applied to the DQ. This voltage is translated into the appropriate signal and stored in the selected memory cell. During a read operation, data read from the selected memory cell appears at the DQ once access is complete and the output is enabled (/OE low). At most other times, the DQs are in a high impedance state; they do not source or sink any current, and do not present a signal to the system. This also prevents DQ contention when two or more devices share the data bus.

IBM - Thinkpad A30P Review

Designed as powerful desktop replacement notebooks, the Thinkpad A series laptops from IBM combine performance with notebook versatility. The latest improvements to the range see the introduction of the new Mobile Intel Pentium 4 Processor-M.

Housed in the familiar black, composite, titanium chassis, the Thinkpad A30P is powered by a 1.6GHz P4-M backed by 256MB of PC2100 DDR SDRAM. It can accommodate up to a maximum of 1GB of memory through two DIMM slots. The CPU speed drops to 1.2GHz when running under battery power and the 4,000mAh battery gives a reasonable life of two and a half hours.

The Thinkpad A30P comes with two modular drive bays; an Ultrabay and an Ultrabay Plus. Both of these can accept a number of other drives as well a second battery, but the Ultrabay Plus has the added advantage that it can also accept either a Workpad (Palm) cradle or a numeric keypad.

Only the basic Ultrabay was used in the review system, occupied by a DVD/CD-RW 8x/8x/24x/8x combo drive. For internal storage there is 40GB IBM hard drive, so working with large amounts of data shouldn't pose too much of a problem. There are also two Type II PC Card slots, which are stacked so they can also take a Type III card.

The 1400 x 1050 pixel TFT screen is driven by a 32MB ATI Mobility Radeon 7500 graphics adapter. This is an AGP 4X chipset that uses DDR memory, which gives the Thinkpad A30P true 3D performance: maybe not enough to run the more power-hungry 3D games, but at least you can play some of them - and that's a rarity in a notebook.

One of the Thinkpad A30P's strongest points is its connectivity; in addition to an Intel Pro/100VE network adapter and a 56Kbps, V.92-capable modem, it also comes with wireless networking, so there should be no problem connecting the Thinkpad A30P with the outside world.

All the usual I/O connectors are on the rear panel; serial, parallel, VGA, two USB, modem, LAN and S-Video, while the sides of the chassis house the three audio ports and infra-red port, but strangely no FireWire port.

The keyboard is well positioned and the whole unit has a high degree of build quality; the keys are responsive, as is the trackpoint and the three mouse buttons. Situated on the left hand side of the keyboard are six Internet navigation buttons; mail, home, search, favourites, reload and stop, the first three of which can be user-configured. Above the keyboard are the volume controls and a button to access the online Thinkpad help software.

IBM - Thinkpad A30P features - Verdict

The IBM Thinkpad A30P is a powerful, well-specified but pricey addition to the Thinkpad range of desktop replacement laptops. It combines good performance with an outstanding array of connectivity features.

IBM - Thinkpad A30P price

2,470 + VAT

IBM: 0800 169 1458

www.pc.ibm.com/uk

How To Select The Best Gaming Laptops

A Laptop Buying Guide For Gamers

Most veteran PC gamers know exactly what they want in a gaming laptop, and those who have the time and money have probably already built their dream computer themselves, but if you are a little newer to the field, a little more fond of the smaller notebook footprint, or a little less comfortable with a do-it-yourself computer, you need to be armed with these basic facts before purchasing your gaming laptop.

The three most important components for any high-end laptop are the processor, RAM and graphics card. Since you are building a gaming rig, you will want to focus on your graphics card first and foremost. Make sure you load up the video memory with at least 256MB and remember to select a notebook that has a dedicated graphics card. Integrated graphics simply cannot handle any modern, 3D gaming.

The next most important component is your processor. Dual-core CPUs are the hottest thing out right now. Ideally, you want to stay within the top two or three fastest dual-core CPUs, in terms of processor speed, that are currently available at the time of your purchase. This will ensure that your notebook is fully optimized for all of today s latest 3D games.

The third most important factor in the speed of your laptop is RAM. You will need at least 1GB to safely play most 3D games without any memory bottlenecking, although most hardcore gamers opt for 2GB or more just for the added punch and/or bragging rights.

The fourth and final tip would be to go with 7200rpm hard drives, as these will definitely speed up load times by adding some extra horsepower to your gaming machine.

With recent advancements in mobile technologies, laptops are now becoming more and more popular in the gaming community, as the prospect of a portable gaming rig that can produce desktop-like performance on the go is something that appeals to all gamers. Just remember to follow these four simple guidelines to ensure that your laptop will be able to meet or exceed all of the hardware requirements for your gaming sessions.

How to Set Up a RAID Array - part 1

This tutorial will take you through the steps involved in setting up a RAID array. In this case the array will be a single RAID 1 (mirror) array, set up in the context of a new system build in which the RAID array is partitioned and Windows XP installed in the C: partition. The tutorial will cover each of the following:

creating a floppy containing the third party RAID Controller drivers
configuring the RAID array
installing the RAID Controller drivers
partitioning the RAID array
formatting the drive partitions
installing Windows.

In the case of this tutorial, the controller in question is an integrated GigaRAID (IT8212) ATA RAID Controller. The procedure outlined will be similar for other manufacturer's controllers.

Integrated RAID controllers generally offer support for a reduced subset of RAID levels. In the case of the IT8212 controller, five configurations are supported:

RAID level/Type	Configurations	Number of disks
RAID 0	Disk Striping	2, 3 or 4
RAID 1	Disk Mirroring	2
RAID 0+1	Disk Striping + Mirroring	4
JBOD	Disk Concatenation	2, 3 or 4
Normal	None	1, 2, 3 or 4

The "Normal" mode allows the RAID controller effectively doubles the usual number of EIDE channels provided on a motherboard from 2 to 4 (and the number of devices from 4 to 8).

Reasons to implement RAID

RAID (Redundant Array of Inexpensive Disks) is a system developed whereby two or more disks are physically linked together to form a single logical, large capacity storage device that offers a number of advantages over conventional hard disk storage devices:

superior performance
improved resiliency
lower costs.

There are a number of RAID "levels", each focusing on one or other of these advantages, either singly or in combination. The two principal techniques used are:

striping, and
mirroring.

Striping is the technique to provide increased performance. It is a method of mapping data across the physical drives in an array to create a large virtual drive. The data is subdivided into consecutive segments or "stripes" that are written sequentially across the drives in the array.

Mirroring was the first real implementation of RAID, typically requiring two individual drives of similar capacity. One drive is the active drive and the secondary drive is the mirror, and the technique provides a simple form of redundancy for data by automatically writing data to the mirror drive when it is written to the active drive.

For many years RAID was the preserve of enterprise, server-based systems. However, in recent years, with many desktop motherboards coming equipped with on-board RAID controllers, the technology has moved to the mainstream, where it is being increasingly deployed both for reasons of extracting the maximum level of performance from a system and as a convenient solution to the issue of data security.

Here, we're implementing RAID 1 for the purpose of improved resiliency. Hard disk head crashes may be relatively rare in this day and age, but they can still be a catastrophe when they occur. How many people routinely backup their user data? Indeed, with the size of hard disks these days, how practical is it to institute a conventional data backup regime, to tape or removable disk media?

RAID 1 offers a simple and effective solution ....... transparently! In the event of a disk failure, the RAID controller will simply use the mirror drive for data recovery and continue operation. OK, you'll need to replace the defunct drive to reinstate the former level of resiliency, but you'll not have lost any of your vital user data!

Laptop Backlights and Inverters

Ever switched on your laptop and thought; Hey there s nothing coming on the screen, only to notice as you move it towards you for a better look, the light catches the screen at a different angle and there s a very faint/dark image displayed? In every laptop lcd screen there s a flourescent tube that illuminates the screen from the back (hence the term backlight) if this fails or the mechanism that starts it up fails then your display will become dark/dim to the point of being unreadable.

In our experience; in most cases it s not the backlight (the ccfl tube) that fails, but the circuitry that starts it up called the inverter, a small circuitboard that usually resides just below the lcd panel within the screen lid. As long as the particular inverter is readily available as a spare part then the repair is quite straightforward and simple, swap out the old for the new and it should be as good as new.

Sometime the backlight itself fails, the symtoms are the same, dark screen, faint image etc. The repair is a little more fiddly as lcd screens are not meant to be taken apart, so changing a ccfl tube is not for the light hearted. Of course you could always change the lcd panel, but that seems like hitting a nut with a sledgehammer to break it, it ll also cost you, lcd panels are not cheap. There are companies that do swap out just the ccfl tube, if your in the UK try us at www.laptop-repair-service.co.uk, else have a search on google for laptop backlight repair .

In either case if it happens to you and you just can t give up the laptop for repair even for a few days, and you have a spare pc monitor to hand, you should be able to plug the monitor cable into the laptop and use it with that, not exactly portable but it should get you out of trouble, and allow you to finish that piece of work with the looming deadline.

Graph Data Structures - Database Internals

Database internals

Storage

Database tables/indexes are typically stored in memory or on hard disk in one of many forms, ordered/unordered Flat files, ISAM, Heaps, Hash buckets or B+ Trees. These have various advantages and disadvantages discussed in further in the main article on this topic. The most commonly used are B+trees and ISAM.

Indexing

All of these databases can take advantage of indexing to increase their speed, and this technology has advanced tremendously since its early uses in the 1960s and 1970s. The most common kind of index is a sorted list of the contents of some particular table column, with pointers to the row associated with the value. An index allows a set of table rows matching some criterion to be located quickly. Typically, indexes are stored in the same various techniques mentioned above (such as B-trees, hashes, and linked lists). Usually, a specific technique is chosen by the database designer to increase efficiency in the particular case of the type of index required.

Relational DBMSs have the advantage that indexes can be created or dropped without changing existing applications making use of it. The database chooses between many different strategies based on which one it estimates will run the fastest. In other words, indexes are transparent to the application or end user querying the database; while they affect performance, any SQL command will run with or without indexes existing in the database.

Relational DBMSs utilize many different algorithms to compute the result of an SQL statement. The RDBMS will produce a plan of how to execute the query, which is generated by analyzing the run times of the different algorithms and selecting the quickest. Some of the key algorithms that deal with joins are Nested Loops Join, Sort-Merge Join and Hash Join. Which of these is chosen depends on whether an index exists, what type it is, and its cardinality.

Transactions and concurrency

In addition to their data model, most practical databases ("transactional databases") attempt to enforce a database transaction . Ideally, the database software should enforce the ACID rules, summarized here:

Atomicity: Either all the tasks in a transaction must be done, or none of them. The transaction must be completed, or else it must be undone (rolled back).
Consistency: Every transaction must preserve the integrity constraints the declared consistency rules of the database. It cannot place the data in a contradictory state.
Isolation: Two simultaneous transactions cannot interfere with one another. Intermediate results within a transaction are not visible to other transactions.
Durability: Completed transactions cannot be aborted later or their results discarded. They must persist through (for instance) restarts of the DBMS after crashes
A cascading rollback occurs in database systems when a transaction (T1) causes a failure and a rollback must be performed. Other transactions dependent on T1's actions must also be rolled back due to T1's failure, thus causing a cascading effect.

In practice, many DBMS's allow most of these rules to be selectively relaxed for better performance.

Concurrency control is a method used to ensure that transactions are executed in a safe manner and follow the ACID rules. The DBMS must be able to ensure that only serializable, recoverable schedules are allowed, and that no actions of committed transactions are lost while undoing aborted transactions.

Replication

Replication of databases is closely related to transactions. If a database can log its individual actions, it is possible to create a duplicate of the data in real time. The duplicate can be used to improve performance or availability of the whole database system. Common replication concepts include:

Master/Slave Replication: All write requests are performed on the master and then replicated to the slaves
Quorum: The result of Read and Write requests are calculated by querying a "majority" of replicas.
Multimaster: Two or more replicas sync each other via a transaction identifier.

Security

Database security is the system, processes, and procedures that protect a database from unintended activity.

Applications of databases

Databases are used in many applications, spanning virtually the entire range of computer software. Databases are the preferred method of storage for large multiuser applications, where coordination between many users is needed. Even individual users find them convenient, and many electronic mail programs and personal organizers are based on standard database technology. Software database drivers are available for most database platforms so that application software can use a common application programming interface (API) to retrieve the information stored in a database. Two commonly used database APIs are JDBC and ODBC. A database is also a place where you can store data and then arrange that data easily and efficiently.

Acer - TravelMate 351TEV Review

At just 21mm high, the Acer TravelMate 351TEV is the thinnest notebook featured here. Enclosed in a magnesium alloy casing, not only is it tough, it also weighs a respectably low 1.8kg. And, powered by a 700MHz Mobile Pentium III chip and 128MB of system memory, it performs well too.

But the TravelMate 351TEV really stands out when it comes to connectivity. Not only is there an integrated V.90 modem and 10/100Mbps Fast Ethernet module, but there is also an IEEE1394 (FireWire/iLink) port, plus Acer's integrated InvLink IEEE 802.11b wireless LAN solution, and the TravelMate also has Bluetooth capability already built in. That's a very impressive comms spec.

The Acer EasyLink module included with our review system had a floppy drive and the optional 8-speed DVD-ROM drive installed, the other option being a 24-speed CD-ROM drive. The 13.1-inch screen is bright and clear, and has a native resolution of 1024 x 768 pixels, powered by the Trident CyberBlade 8MB graphics chipset.

With the loss/theft of notebooks regularly in the news, the TravelMate has another advantage; it comes with an integrated Smart Card reader, with PlatinumSecret Smart Card software and Smart Card, giving users the chance to lock the system against unauthorised entry.

The keyboard feels well built and is positive to the touch, and a novel design feature is that the keyboard is actually curved, supposedly to make it efficient and easy to use; it certainly feels comfortable. There are five programmable quick launch buttons and a large LED-equipped button informs you when you have e-mail. Quite surprisingly, the TravelMate 351TEV we reviewed came with Windows ME pre-installed.

The Acer TravelMate 351TEV is one of the stars of this group of notebooks. Performing well and with a stunning host of connectivity options, it represents good vale for money.

Acer - TravelMate 351TEV price

1,749 + VAT

Acer: 0870 9002237

www.acer.co.uk

Windows XP Pro Home Speed Up Optimization Performance Steps

Is your XP-running computer slow to be of much use or frustrating? It
may not be your computer's fault. Windows XP, when used correctly,
could be speedy, efficient, and fun to make use of. Here's how to
speed up your XP method.

1. Convert your hard drive to NTFS. If your drive is using FAT16 or
FAT32, you can gain performance by converting it to NTFS.

2. Remove Malware from your method.. adware comes bundled with loads
of free application found on the net. It can slow your machine down to
a crawl. Download and install Spybot Search & Destroy[1], start your
computer in Safe Mode and give your machine a full scan for adware.
For more free security programs

To do so, click on the start menu, go to Run, type cmd. type "CONVERT
C: /FS:NTFS" (without quotes). Follow the instructions and your drive
will be converted to NTFS. Bear in mind that NTFS drives can only be
accessed by Windows 2000/NT/XP and Vista. Older versions of Windows
are only compatible with fat, FAT16 and FAT32.

4. Disable the Indexing Service. The indexing service scans your hard
drive and indexes files to help speed up searching. It runs in the
background using up memory and processor time, and is usually thought
to be unnecessary by most nerds and/or geeks. It can also wake you up
if your hard disk is noisy and you leave your machine on at night. To
disable the Indexing Service, open My computer, Right-click on the
hard drive, go to properties and click on the check box to clear the
check mark next to "Allow indexing service to index this hard drive
for quicker searching". Click OK. It may take some time for the
operation to complete.

3. neat registry database. Cleaning of registry can always speed up
windows xp significantly as there's thousands of calls to registry
file by windows and other programs in one sec means file needs to be
compact.

5. Reduce Visual Effects Reduce Windows XP can look nice ...but
displaying all the visual items can waste method resources. To
optimize, go to Start, right click My computer, and go to the Advanced
tab in the Performance area click Settings, and choose "Adjust for
best performance". in case you still need to keep the look of Windows
XP, you can leave the last 3 check boxes chosen. it is recommended
that you do uncheck these boxes when installing a sizable or graphics
heavy program (like the Adobe programs). Sometimes unchecking these
will help rendering pics, movies or listening to music.

6. To speed up folder browsing: Open My computer > click on the Tools
menu Folder Options, look for View tab>Uncheck the Automatically
search for network folders and printers and Launch folders in a
separate method check box > Click Apply > Click OK.

7. To increase computer download speed go to: google.com and type in
to the search bar tcp optimizer and click the first link. Download the
program and run it. one time open go to File > Backup current settings
and save it. one time saved adjust your speed to what your max net
speed it suppose to be. Than click on optimal settings than apply and
reboot. Then your download speed ought to increase.

8. To make menus load quicker, go to Start, click on Run, and then
type regedit and press Enter/Return. Now find
"HKEY_CURRENT_USER\Control Panel\Desktop", Select MenuShowDelay, right
click and choose Modify , reduce the number to around 100, but not
less.

10. Speeding up Folder Access, disable Last Access Update. Go to Start
and then Run... and type regedt32, click through the file method until
you arrive at HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\FileSystem ,
Right-click in a blank area of the window on the right and choose
DWORD Value to generate a brand new DWORD Value. Call it
NtfsDisableLastAccessUpdate and then Right click on the new value and
choose alter, change the worth information to 1, and press enter.

9. Disabling unnecessary services. Windows XP offers loads of services
and there run lots of programs that take up method resources and you
may seldom need those programs. Below is a list of services that can
be disabled on most machines: Alerter, Clipbook, computer Browser,
Distributed Link Tracking Client, Indexing Service, IPSEC Services,
Messenger, Netmeeting Remote Desktop Sharing, transportable Media
Serial Number, Remote Desktop Help Session Manager, Remote Procedure
Call Locator, Remote Registry, Secondary Logon, Routing & Remote
Access, Server, SSDP Discovery Service, Telnet, TCP/IP NetBIOS Helper,
Upload Manager, Universal Plug and Play tool Host, Windows Time
wireless Zero Configuration (Do not disable in case you use a wireless
network). To disable these services go to Start Run... and type
services.msc, double click on the service you need to change, change
the startup type to Disable.

12. Improve swapfile performance. (Note: some people say that this
only helps on Win9x and is useless for Windows NT based systems,
including WinXP and Win2000). It fundamentally makes sure that your
computer makes use of every last drop of memory (faster than swap
file) before it starts using the swap file.Go to Start, click Run,
type msconfig and then press Enter. Click on the method.ini tab, and
expand the 386enh tab by clicking on the and sign. click on new then
in the blank box type ConservativeSwapfileUsage=1". Press enter, and
restart your computer to see the changes taking place.

11. How to improve boot times Go to Start Menu and Click Run, then
type in regedt32 then press Enter. Find
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Dfrg\BootOptimizeFunction ,
Select Enable from the list on the right, right click on it and
choose alter, change the worth to Y to enable, and press enter, and
close the window. Now click on Start, click on Run, type in msconfig
and click OK. Click on the Startup tab and uncheck every item you
don't need. Do NOT disable entries added by antivirus and antispyware
programs as doing so will make your computer more vulnerable to
viruses and malware.

13. Improve your XP's shutdown speed. This tweak reduces the time that
XP takes before automatically closing any jogging programs when you
give it the command to shutdown. Go to Start, run, and then type
regedt32 and press Enter. Find "'HKEY_CURRENT_USER\Control
Panel\Desktop", right click WaitToKillAppTimeout and choose Modify
and then change the worth to 1000, and press enter. Right click
HungAppTimeout and choose alter. Change the worth to 1000. Press enter
and find "HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control", right
click WaitToKillServiceTimeout and choose Modify and then change the
worth to 1000, and press enter.

14. Removing the background picture on your desktop. Right click the
Desktop click Properties, and go to the Desktop Tab. change the
wallpaper to None. This will greatly speed up windows xp and while
your at it go to the Settings Tab, Colour Setting, and change it to
Medium (16 bit).

Tips

15. Removing undesirable programs Go to Start, Control panel click Add
or Remove Programs, remove undesirable programs and free up some
space.

Warnings

it is advisable to make a back up for your disks before beginning this
because in case you mess up it can do loads of destroy to your
computer's hard drive.
Most changes happen after you reboot.
you can easily make a restore point in Start/Accessories/System
Tools/System Restore. It will then give you the option to generate a
restore point or return to one you created earlier. This will be nice
if something happens to your computer while you are trying to speed it
up and you need to return to when you made the point. This may be
different in Vista but in case you put method Restore in the search
box, you ought to be able to still get there.
The Wireless Zero Configuration can be disabled if a program other
than Windows monitors wireless connectivity.
Deleting your temp files will also help a tiny. To do that go to
"Start", click "Run", in the window that comes up type temp and start
deleting.
To open the "Run" dialog in Windows Vista or Windows 7, type "Run" in
to the search box, then press enter.
it is a nice idea to defragment the drive after you do the other steps.

WarningsPlease be cautious! in case you don't know what you're
actually doing, don't do it, you may well slow down your computer,
change something you cannot basically change back, or even destroy
your method.
There may be steps on this page that don't work for, or even break
your operating method.
Make a back up copy of your disks.
Follow every instruction carefully.
Only get Spybot Search and destroy from safer-networking.org.Other may
be fakes and/or be adware themselves.
Spybot is not related to SpywareBot which is adware.
Before editing the registry, backup the registry first.

How to Install a SCSI Device - part 2

Installing the host adapter

The SCSI host adapter we're going to be installing is a model capable of supporting SCSI-1, SCSI-2 and Fast SCSI-2 devices. This provides a level of performance that's more than adequate for the SCSI devices it's intended to connect to the card.

Locate an unused PCI expansion slot. Unscrew the slot cover and set it aside. Position the host adapter over the PCI slot, and align the bottom edge to the slot s opening. Firmly push the host adapter into the PCI slot, so that it stands perpendicular to the PCI slot.

If you want the LED in your computer to light whenever there is activity on the SCSI bus, disconnect the LED cable from the LED connector on the motherboard and connect it to the LED connector on the host adapter.

Installing an internal device

The SCSI host adapter card allows connection of both internal and external devices.

In this case, the internal device in question is a CD-ReWriter.

Optimize Windows 7 for better performance

No matter how fast or shiny computers might be when they're new, all
of them appear to get slower over time. That state-of-the-art computer
you bought last year might not feel like such a screamer after you
install a dozen programs, load it with antispyware and antivirus
tools, and download untold amounts of junk from the net. The slowdown
might happen so gradually that you not very notice it, until one day
you're trying to open a program or file and wonder, "What happened to
my poor computer?"

Optimize Windows 7 for better performance

Whatever the cause, there's loads of ways to help speed up Windows and
make your computer work better even without upgrading your hardware.
Here are some tips to help you optimize Windows 7 for faster
performance.

Try the Performance troubleshooter

The first thing that you can try is the Performance troubleshooter,
which can automatically find and fix problems. The Performance
troubleshooter checks issues that might slow down your computer's
performance, such as how plenty of users are currently logged on to
the computer and whether multiple programs are walking at the same
time.

Open the Performance troubleshooter by clicking the beginning button ,
then clicking Control Panel. In the search box, type troubleshooter,
and then click Troubleshooting. Under process and Security, click
Check for performance issues.

Delete programs you never use

plenty of computer manufacturers pack new computers with programs you
didn't order and might not need. These often include trial editions
and limited-edition versions of programs that program companies hope
you'll try, find useful, and then pay to upgrade to full versions or
newer versions. If you decide you don't need them, keeping the program
on your computer might slow it down by using precious memory, disk
space, and processing power.

Even if your computer is older, it might contain
manufacturer-installed programs that you never noticed or have since
forgotten about. It's never late to remove these and get rid of the
clutter and wasted process resources. possibly you thought you might
use the program someday, but never did. Uninstall it and see if your
computer runs faster.

It's a cool suggestion to uninstall all the programs you don't plan to
make use of. This ought to include both manufacturer-installed program
and program you installed yourself but don't need any more especially
utility programs designed to help manage and tune your computer's
hardware and program. Utility programs such as virus scanners, disk
cleaners, and backup tools often run automatically at startup, quietly
chugging along in the background where you can't see them. plenty of
people have no idea they're even walking.

Limit how plenty of programs run at startup

For instructions, see Uninstall or change a program.

Decide for yourself if you need a program to run at startup.

plenty of programs are designed to start automatically when Windows
starts. program manufacturers often set their programs to open in the
background, where you can't see them walking, so they'll open right
away when you click their icons. That's helpful for programs you use a
lot, but for programs you never or never use, this wastes precious
memory and slows down the time it takes Windows to finish beginning
up.

But how can you tell what programs run automatically at startup?
Sometimes this is obvious, because the program adds an icon to the
notification area on the taskbar, where you can see it walking. Look
there to see if there's any programs walking that you don t need to
start automatically. Point to each icon to see the program name. Be
sure to click the Show hidden icons button so you don't miss any
icons.

The Show hidden icons button in the notification area
Even after you check the notification area, you might still miss some
programs that run automatically at startup. AutoRuns for Windows, a
free tool that you can download from the Microsoft website, shows you
all of the programs and processes that run when you start Windows. You
can cease a program from walking automatically when Windows starts by
opening the AutoRuns for Windows program, and then by clearing the
check box next to the name of the program you need to cease. AutoRuns
for Windows is designed for advanced users.

Some people prefer to manage which programs run at startup using the
process Configuration tool. For more information, see Start process
Configuration.

Note

Defragment your hard disk

Fragmentation makes your hard disk do additional work that can slow
down your computer. Disk Defragmenter rearranges fragmented
information so your hard disk can work more effectively. Disk
Defragmenter runs on a schedule, but you can also defragment your hard
disk by hand.

neat up your hard disk

For more information, see Improve performance by defragmenting your hard disk.

Unnecessary files on your hard disk take up disk space and can slow
down your computer. Disk Cleanup removes temporary files, empties the
Recycle Bin, and removes a variety of process files and other items
that you no longer need. For step-by-step instructions on how to do
this, see Delete files using Disk Cleanup.

Run fewer programs at the same time

Sometimes changing your computing behavior can have a huge impact on
your PC's performance. If you're the type of computer user who likes
to keep five programs and a dozen browser windows open at once all
while sending instant messages to your friends don't be surprised if
your computer bogs down. Keeping loads of e‑mail messages open
can also use up memory.

If you find your computer slowing down, ask yourself if you need to
keep all of your programs and windows open at one time. discover a
better way to remind yourself to reply to e‑mail messages than
keeping all of them open.

Make sure you're only walking one antivirus program. walking over one
antivirus program can also slow down your computer. Fortunately, if
you're walking over one antivirus program, Action middle notifies you
and can help you fix the issue.

For more information, see What is Action middle?

If Windows is walking slowly, you can speed it up by disabling a few
of its visual effects. It comes down to appearance versus performance.
Would you have Windows run faster or look prettier? If your computer
is fast , you don't must make this tradeoff, but if your computer is
barely powerful for Windows 7, it can be useful to scale back on the
visual bells and whistles.

Turn off visual effects

You can decide which visual effects to turn off, one after the other,
or you can let Windows decide for you. there's 20 visual effects you
can control, such as the transparent glass look, the way menus open or
close, and whether shadows are displayed.

To adjust all visual effects for best performance:

Open Performance Information and Tools by clicking the beginning
button , then clicking Control Panel. In the search box, type
Performance Information and Tools, and then, in the list of results,
click Performance Information and Tools.

Click Adjust visual effects. If you're prompted for an administrator
password or confirmation, type the password or provide confirmation.

Restart regularly

Click the Visual Effects tab, click Adjust for best performance, and
then click OK. (For a less drastic option, select Let Windows decide
what s best for my computer.)

This tip is simple. Restart your computer at least one time a week,
especially if you use it a lot. Restarting a computer is a great way
to clear out its memory and make sure that any errant processes and
services that started walking get shutdown.

Restarting closes all the program walking on your PC not only the
programs you see walking on the taskbar, but also dozens of services
that might have been started by various programs and never stopped.
Restarting can fix mysterious performance problems when the exact
cause is hard to pinpoint.

Add more memory

If you keep so plenty of programs, e‑mail messages, and
web-sites open that you reckon restarting is a hassle, that's probably
a sign you ought to restart your computer. The more things you have
open and the longer you keep them walking, the greater the chances
your computer will bog down and finally run low on memory.

This isn't a guide to purchasing hardware that will speed up your
computer. But no discussion of how to make Windows run faster would be
complete without mentioning that you ought to reckon about adding more
random access memory (RAM) to your computer.

If a computer walking Windows 7 seems slow, it's usually because the
computer doesn't have RAM. The best way to speed it up is to add
more.

Windows 7 can run on a computer with 1 gigabyte (GB) of RAM, but it
runs better with 2 GB. For optimal performance, boost that to 3 GB or
more.

Another option is to boost the amount of memory by using Windows
ReadyBoost. This feature lets you make use of the storage space on
some removable media devices, such as USB flash drives, to speed up
your computer. It s less hard to plug a flash drive in to a USB port
than to open your computer case and plug memory modules in to its
motherboard. For more information, see Using memory in your storage
tool to speed up your computer.

If your computer is walking slowly, it's feasible that it's infected
with a virus or adware. This is not as common as the other problems,
but it's something to reckon about. Before you worry much, check your
computer using antispyware and antivirus programs.

Check for viruses and spyware

adware is a kind of program that's installed, usually without your
knowledge, to watch your activity on the net. You can check for adware
with Windows Defender or other antispyware programs. For more
information, see How to inform if your computer is infected with
adware.

A common symptom of a virus is a much slower-than-normal computer
performance. Other signs include unexpected messages that pop up on
your computer, programs that start automatically, or the sound of your
hard disk constantly working.

Check your computer's speed

The best way to deal with viruses is to prevent them in the first
place. Always run antivirus program and keep going to date. Even if
you take such precautions, however, it's feasible for your computer to
become infected. For more information, see How am I able to inform if
my computer has a virus?

The Windows Experience Index rates your computer on two key parts and
gives you a number for each, as well as an overall base score. This
base score is only as cool as your worst-performing part subscore.

If you try these tips and your computer is still slow, you might need
a brand spanking new computer or some hardware upgrades, such as a
brand spanking new hard disk or faster video card. There's no need to
guess the speed of your computer, however. Windows provides a way to
check and rate your PC's speed with a tool called the Windows
Experience Index.

Base scores currently range from 1 to 7.9. If your computer is rated
lower than 2 or 3, it might be time to reckon about a brand spanking
new computer, depending on what tasks you need to do along with your
computer.

For more information, see What is the Windows Experience Index?

Sorting Algorithms - Quick Sort part 2

Iterative version

Explicit recursion can be avoided using an iterative form of quicksort that replaces the call stack by an explicit stack data structure. Although this does not make the algorithm use asymptotically less time or space, the practical advantage lies in avoiding the time and space overhead of subroutine entry and exit that occurs during general recursive calls. The disadvantage is considerably greater code complexity. A simpler in-place sort of competitive speed is heapsort.

 function QuickSort(Array, Left, Right)

var

     L2, R2, PivotValue

 begin

     Stack.Push(Left, Right);       // pushes Left, and then Right, on to a stack

     while not Stack.Empty do

     begin

         Stack.Pop(Left, Right);    // pops 2 values, storing them in Right and then Left

         repeat

             PivotValue := Array[(Left + Right) div 2];

             L2 := Left;

             R2 := Right;

             repeat

                 while Array[L2] < PivotValue do // scan left partition

                     L2 := L2 + 1;

                 while Array[R2] > PivotValue do // scan right partition

                     R2 := R2 - 1;

                 if L2 <= R2 then

                 begin

                     if L2 != R2 then

                         Swap(Array[L2], Array[R2]);  // swaps the data at L2 and R2

                     L2 := L2 + 1;

                     R2 := R2 - 1;

                 end;

             until L2 >= R2;

             if R2 - Left > Right - L2 then // is left side piece larger?

             begin

                 if Left < R2 then

                     Stack.Push(Left, R2);

                 Left := L2;

             else

             begin

                 if L2 < Right then // if left side isn't, right side is larger

                     Stack.Push(L2, Right);

                 Right := R2;

             end;

         until Left >= Right;

     end;

 end;

Extensions might include a median-of-three selection of the pivot (with re-ordering during that selection), and the use of InsertionSort for any partition less than (say) eight elements in length.

Parallelization

Like mergesort, quicksort can also be easily parallelized due to its divide-and-conquer nature. Individual in-place partition operations are difficult to parallelize, but once divided, different sections of the list can be sorted in parallel. If we have p processors, we can divide a list of n elements into p sublists in Θ(n) average time, then sort each of these in O((n/p) log(n/p)) average time. Ignoring the O(n) preprocessing, this is linear speedup. Given Θ(n) processors, only O(n) time is required overall.

One advantage of parallel quicksort over other parallel sort algorithms is that no synchronization is required. A new thread is started as soon as a sublist is available for it to work on and it does not communicate with other threads. When all threads complete, the sort is done.

Other more sophisticated parallel sorting algorithms can achieve even better time bounds. For example, in 1991 David Powers described a parallelized quicksort that can operate in O(log n) time given enough processors by performing partitioning implicitly.

Competitive sorting algorithms

Quicksort is a space-optimized version of the binary tree sort. Instead of inserting items sequentially into an explicit tree, quicksort organizes them concurrently into a tree that is implied by the recursive calls. The algorithms make exactly the same comparisons, but in a different order.

The most direct competitor of quicksort is heapsort. Heapsort is typically somewhat slower than quicksort, but the worst-case running time is always O(n log n). Quicksort is usually faster, though there remains the chance of worst case performance except in the introsort variant. If it's known in advance that heapsort is going to be necessary, using it directly will be faster than waiting for introsort to switch to it. Heapsort also has the important advantage of using only constant additional space (heapsort is in-place), whereas even the best variant of quicksort uses Θ(log n) space. However, heapsort requires efficient random access to be practical.

Quicksort also competes with mergesort, another recursive sort algorithm but with the benefit of worst-case O(n log n) running time. Mergesort is a stable sort, unlike quicksort and heapsort, and can be easily adapted to operate on linked lists and very large lists stored on slow-to-access media such as disk storage or network attached storage. Although quicksort can be written to operate on linked lists, it will often suffer from poor pivot choices without random access. The main disadvantage of mergesort is that, when operating on arrays, it requires Ω(n) auxiliary space in the best case, whereas the variant of quicksort with in-place partitioning and tail recursion uses only O(log n) space. (Note that when operating on linked lists, mergesort only requires a small, constant amount of auxiliary storage.)

ACI - Precedent Review

The ACI Precedent gets off to a good start by being more or less identical to Dell's Inspiron 5000, which has received a deservedly good press elsewhere. This particular Precedent does differ in one respect, namely that it has a Pentium III/600 processor, not the SpeedStep PIII/650 used by Dell.

Physically, the Precedent is quite imposing, with a moderately large footprint necessary to accommodate its 15-inch screen. The body of the machine is soundly constructed and doesn't flex or deform unduly under pressure, and you get the benefit of a magnesium alloy lid as well, ensuring the longevity of the screen. The build quality and the fact that the Precedent is an all-in-one design could have had an unfortunate effect on the weight, but the engineers have actually managed to keep this down to 3.4kg, which isn't bad for a well-made desktop replacement notebook.

Judging from the spec, this machine is intended to be taken seriously, with 128MB of SDRAM and a 12GB Toshiba hard disk backing up the processor, plus a 6-speed Toshiba DVD-ROM drive in a special bay which can also be used for options like an LS-120 Superdisk or a second battery pack.

The Precedent comes as standard with an internal V.90 Lucent fax modem, so its two Type II PC Card slots remain free for other uses, such as network adapters. The ports at the rear include both USB and an S-video output for use with a television set, giving the machine the potential for use as a DVD movie player. There's a connector for an optional port replicator or docking station as well.

One of the things that we particularly liked about this notebook was its keyboard, which proved to be large enough to be used in comfort for prolonged periods. It avoided irritants like non-standard function-doubling to save space, and the Enter and Backspace keys were pleasingly large and easy to hit.

Users needing to get serious work done will also appreciate the 15-inch TFT screen, which is large enough to produce a really readable Windows workspace at XGA resolution (1024 x 768). The panel was also reasonably brightly illuminated, which is another point in its favour.

Performance isn't a problem with this machine, so buyers wanting a business system with some punch shouldn't be disappointed. The battery life wasn't outstanding, seeming to average out at a little under the three hour mark, but we'd still class this as acceptable for a power portable. With any luck, ACI will introduce faster versions based on Speedstep processors, and edge the running time up over three hours.

ACI - Precedent features - Verdict

The Precedent is a decent piece of kit, and for what it is, the price is fair. There are still far too many overpriced PIII notebooks out there, and it's encouraging to find machines like this at a more sensible price. Strong on ergonomics and build quality, it's a powerful, good value system that's worth taking seriously.

ACI - Precedent price

1,899 + VAT

ACI: 0818 830 1958

www.aciplc.com

How to Install a Front Loading Drive - part 7

Installing a floppy drive

Despite the fact that it's 1.44MB capacity is minuscule by today's standards and that BIOSes have supported booting from higher capacity alternatives for several years now, most PCs continue to ship with a standard floppy disk drive.

In acknowledgement of it's extraordinary longevity therefore, this tutorial is going to use a standard floppy disk drive - albeit a rather smart-looking black one! - as an example of how to install a front-loading 3.5in drive.

Over the years there have been two principal contenders for superseding the standard 3.5in floppy disk drive:

Iomega's Zip drive, and
Imation's SuperDisk drive

and, on the face of it, both appear just right for taking over the traditional functions of a floppy disk - serving as an emergency boot device, moving a few files between systems, archiving or backing up individual files or directories and sending files by mail.

Launched in 1995, the original Zip drive had a capacity of 94MB and was available in both internal and external versions. The secret of the Zip's good performance (apart from its high 3,000rpm spin rate) was a technology pioneered by Iomega (based on the Bernoulli aerodynamic principle) which actually sucks the flexible disk up towards the read/write head rather than vice-versa. The disks are soft and flexible like floppy disks, which makes them cheap to make and less susceptible to shock.

The internal units fit a 3.5in bay, came with a choice of SCSI or ATAPI interface and boasted an average 29ms seek time and a data transfer rate of 1.4 KBps. External units originally came in SCSI or parallel port versions only. However, the Zip 100 Plus version, launched in early 1998, offered additional versatility, being capable of automatically detecting which of these interfaces applied and operating accordingly. The range was further extended in the spring of 1999 when Iomega brought a USB version to market. In addition to the obvious motivation of Windows 98 with its properly integrated USB support, the success of the Apple iMac was a key factor behind the USB variant. Apple's somewhat bizarre decision to omit a floppy drive had left people crying out for a removable storage option - and, of course, iMacs sport USB ports as standard.

The end of 1996 saw the long-awaited appearance of OR Technology's LS-120 drive. The technology behind the LS-120 had originally been developed by Iomega, but was abandoned and sold on to 3M. The launch had been much delayed, allowing the rival Zip drive plenty of time to become established. Even then, the LS-120 was hampered by a low-profile and somewhat muddled marketing campaign. Originally launched under the somewhat confusing brand name "a:DRIVE", the LS-120 was promoted by Matsushita, 3M and Compaq and was initially available only ready-installed on the latter's new range of Deskpro PCs. Subsequently, OR Technology offered licences to third-party manufacturers in the hope that they would fit the a:DRIVE to their PCs instead of a standard floppy.

However, it was not until 1998, when Imation Corporation - a spin-off of 3M's data storage and imaging businesses in the summer of 1996 - launched yet another marketing offensive under the brand name "SuperDisk", that the product begin to meet with any serious success in the marketplace.

A SuperDisk diskette looks very similar to a common-or-garden 1.44MB 3.5in disk, but uses a refinement of the old 21MB floptical technology to deliver much greater capacity and speed. Named after the "laser servo" technology it employs, an LS-120 disk has optical reference tracks on its surface that are both written and read by a laser system. These "servo tracks" are much narrower and can be laid closer together on the disk: an LS-120 disk has a track density of 2,490tpi compared with 135tpi on a standard 1.44MB floppy. As a result, an LS-120 disk was capable of holding 120MB of data.

While its 450 KBps data transfer rate and 70ms seek time made it of the order of 5 times faster than a standard 3.5in floppy drive, it's comparatively slow spin rate of 720rpm mean that the original LS-120 was not as fast as a rival Zip drive. However, this performance lag was more than offset by the LS-120's principal advantage over the Zip, backward compatibility. As well as the 120MB SuperDisk diskettes the original LS-120 was also capable of using standard 1.44MB and 720KB floppy disks, which are handled with a 3-fold speed improvement compared with a standard floppy drive.

Despite both manufacturers releasing higher capacity models, neither device has succeeded in completely replacing the traditional floppy disk drive, probably because neither is completely compatible with it. That both devices use up a valuable IDE connection rather than the floppy disk interface is likely one reason. The fact that both Zip and SuperDisk drives have succeeded in winning a significant market share - thereby reducing the portability of media benefit of either - is, perhaps, another.

Some information on Computer Help and Support to use your system

Computer can be defined as a machine that manipulates data according to a list of instructions. Computers are extremely versatile and distinguished from calculators as it has the ability to store and execute lists of instructions called programs.

As a computer is an electronic machine it can cause problems so we need to be aware of computer help and support. Our computer problems mostly occur when we have tons of work to be completed and we have delayed it until the last minute. The common issues that happen with computers are like error messages, computer hangs up or freezes. These are basic or rather simple problems that can be easily fixed at home even if we don t possess great technical skills.

For people who frequently use a computer must be surely aware of the error messages that appear while operating it. Especially, those who use Windows witness more of these errors.

A lot of people are really skeptical of opening their own computer (PC) for servicing as it seems really confusing to them. The thought itself is so scary that they end up sending their PCs to expensive repair shops. However, it s not all that difficult as it seems. Further mentioned are lists of things that will help getting in and out of a computer.

Earlier we only had the option of taking help from the computer hardware or software expert for its repair. Nowadays, online computer repair services are also available. This saves a lot of our time and money too. Today no one would want to compromise on the computer safety to money or time.

The computer needs to be maintained on a regular basis. The improved performance of the computer majorly depends on what we do on it.

Let s learn some very basic but still important ways of taking care of the system:

Never turn off the computer with the power switch until Windows has shut down.
The first point has an exception though. We can turn the power switch off when the computer gets locked or the hard drive is not responding.

These are some basic points which will in turn help in saving data properly, prevent permanent hard disk defects and will prevent a lot of windows problems.

Getting on to online computer help and support, a high speed internet connection and good technicians can safely and firmly repair our computer system closely. The PC is diagnosed using different tools when a problem is found it s diagnosed and repaired while we remain comfortably at home. Having this service online is like almost having a personal technician for our PC.

Nowadays, in our busy lives we don t have much time to spend on the computer repairs. Herein, tech support recommends nice methods to get familiar with the details involved in the system.

These days a lot of online support organizations which offer many different computer repair services. Some of these services are: mail Setup and Support, safe internet browsing, computer setup advice, troubleshooting errors, data backup and recovery, virus and spyware removal root kit, repairs, up-gradations, and installations for new system, networking and more. The technicians who perform these services are highly trained computer technicians. Though it s a costly affair it s very efficient and effective.

VoIP (Voice Over IP) Explained

Telephone calls through broadband: this is the future of telephony. Voice Over Internet Protocol (VoIP) technology represents a revolution in the way we communicate. Here's an outline of three of the most common ways that VoIP can be used to make cheap phone calls. You've probably heard about new technology that allows people to use broadband to make cheap phone calls. Perhaps you already make calls or video-calls yourself from your computer. Whatever you know already, it helps to have a clear, basic grasp of how this exciting new generation of telephone services works and how it can be used. The technical name for making cheap phone calls using broadband is 'Voice Over Internet Protocol'. Some people call it 'Voice Over IP', or even 'VoIP' (say "voyp"). Perhaps you've heard of 'VoIP phones'. VoIP is, basically, the umbrella term for the technology for making telephone calls using the Internet and broadband. It uses audio systems to encode speech in a way that means that it can be transmitted digitally over an Internet Protocol network. There are many ways of using VoIP technology and a broadband connection to make phone calls. Here are three of the most common. 1. PC to PC The first, simplest and typically free way to use VoIP is 'PC to PC'. For this, you'll need to be at your computer, as will the person you're calling. You'll also both need a headset/microphone/speaker. And you'll need either USB VoIP phone, which plugs into your computer's USB socket. If you don't have that, you can install or download a piece of software called a 'softphone'. This allows VoIP calling without dedicated equipment. Though this is undoubtedly the cheapest way to make VoIP calls, the call quality is often not great. And you're tied to your computer. 2. PC to Phone The second popular way to use voice over IP is by using your PC or computer to call a normal landline or mobile phone. The advantage of this is that the person you're calling doesn't need to have signed up with the same service, doesn't need all the equipment etc. You, though, will be charged for these 'outage' calls. And you are, as above, tied to your PC. 3. Phone to Phone A VoIP provider sends you a VoIP adaptor. You use this to connect your normal digital cordless ('DECT') telephone to the broadband modem / router on your computer. Once you've installed the VoIP provider's software (this converts the analog signal to a digital one), you continue to use your phone exactly as before, using your existing broadband connection to make cheap telephone calls. To call, you pick up your existing digital cordless (DECT) phone and dial as normal. Your computer doesn't even need to be switched on. When their phone rings at the other end, they answer as normal. The beauty of this final method of using voice over IP is that your computer doesn't even have to be switched on for you to use the VoIP technology and broadband to make calls. The person you're calling doesn't have to have signed up to the same VoIP provider. Nor do they need to have broadband, or be at their computer. In fact, they don't even need to have a computer. So there it is - three of the most common ways in which you can now use VoIP technology to make cheap phone calls.

Optimizing Memory Card Performances

A memory card is an extension card, which can be inserted into a multitude of appliances like a computer, a digital camera, a personal digital assistant, a smart phone or an MP3 player. The memory card is used to extend the memory capacity of the host device.

Multiple integrated circuit devices that are interconnected using a circuit board substrate make a memory card. A memory card or a flash memory card is a solid-state electronic flash memory data storage device, which offers high re-record ability, power free storage (memory card is a non-volatile memory device with a compact housing which is in no need of power source to retain its memory contents) and enduring environmental limitations. Non-solid state memory cards that do not use flash memory are also available (also known as Mem-cards).

There are different types of memory cards available such as a Random Access Memory card (RAM), a Read-only Memory Card (ROM) and an electrically erasable programmable read-only memory (EEPROM) card and a flash memory card.

A flash memory card represents first logic state of the binary state system storing charge on a floating gate and the second logic state of the binary state system is signified by the absence of stored charges.

A memory card can perform a write operation, a read operation and an erase operation. There are four major types of memory cards (based on their storage and specification) like compact flash, secure digital, memory stick and xD. Each one of the memory cards characteristically conforms to a specific form factor of the standard and has a unique connector, which conforms the electrical and mechanical interface of the cards to the respective standards.

In 1990s, a number of memory cards formats smaller than PC card came out (like Compact flash, smart media and miniature card) and also tiny embedded memory. With the invention of ultra small cards for cell phones, PDAs and Compact digital cameras, the previous generation of compact cards were looking big. In industrial fields, even the vulnerable PC card memory cards manage to maintain a slot unlike in cell phone and PDA market.

Nowadays personal computers have built in slots for more than one memory card like memory stick, compact flash, SD, etc. to ensure compatibility.

There are two types of software available in memory card namely, memory card Data Recovery Software and Memory card File Recovery Software. Memory Card File recovery software is designed to recover images, movies, sound and other data files from all types of digital media and compatible with major memory card devices. The memory card filed recovery software does a deep scanning of the media at the lowest level to recover and retrieve the deleted photos. Memory Card File Recovery Software is fast and easy and does not require any scientific enterprise for the recovery process and this online recovery is a safe technique. Just insert the memory card into a USB card reader and run the memory card file recovery software to rescue it to a safer location.

Memory card Data Recovery Software recovers lost pictures, images, photos, audio and video files and folders from all memory card storage media flash drive, multi media memory card, mobile communicator, mobile PC and hand held computers. This memory card data recovery software recovers data even when the media is corrupted or memory card is pulled out from their running device. In addition it recovers data even if Windows displays drive not formatted message. It is the easiest and quickest software utility tool for any type of digital file folders to recover, retrieve, rescue, repair or restore the data.

Digital Camera Functions and their uses

In the past few years, most people have upgraded from cameras that use film to digital cameras, which store images electronically using either flash memory, or in some cases, a hard disc drive. These modern cameras have a number of advantages over traditional film cameras, but perhaps the most notable is the ability of digital cameras to store hundreds of photographs, and allow for images to be uploaded onto a computer for editing and storage.

Typically, digital camera functions, even on the most basic models now exceed those available on comparable compact film cameras, and offer everyone the chance to take great photos.

Although image quality on digital cameras has traditionally been somewhat lower than that available on a typical 35mm camera, thanks to the resolution of the light sensitive chips that collect the image data, with the latest generations of models, the image quality matches or even exceeds that of their competitors.

One of the most impressive digital camera functions is the ability of the photographer to instantly see what they have taken a photo of. This is achieved using the screen on the back of the camera, which can show the picture straight away, and allow users to decide whether or not they want to keep the picture, rather than having to wait until the film is developed.

Most digital cameras now allow users to perform a certain degree of image manipulation through the use of their inbuilt software. Functions range from being able to take pictures in black and white through to being able to zoom in on a particular area of the image, and crop it from the whole easily.

When a digital camera is coupled with a PC that has image management software such as Adobe Photoshop, it is possible to add all manner of effects and stitch different pictures together in order to create a montage that would be very difficult using traditional media.

If there is enough memory available, digital camera functions also include the ability to take short videos with sound, making them a viable alternative to an expensive dedicated video camera for capturing special moments in all their glory.

Thanks to the Internet, and websites such as Flickr, digital camera owners can share their pictures with friends from all over the world in a matter of seconds, allowing almost anyone to have instant access to pictures of an event, and this has created a revolution in the way that news events can be covered in real time.

Sharp - PC-UM10 Muramasa Review

Named after a legendary Japanese swordsmith, the PC-UM10 Muramasa from Sharp is one of the thinnest notebooks currently available, and has been designed to compete with Sony's Vaio range. Its brushed aluminium surfaces and magnesium alloy chassis, together with its weight of only 1.3kg, give it a stylish look and feel.

To get to such a thin design - the PC-UM10 is just 20mm thick at its thickest point - a lot of connectivity has had to be sacrificed. There are no built-in Bluetooth wireless, infrared or serial ports but you do get an integrated LAN and a modem port. To aid in its thin design the keyboard has been engineered so that it rises out of the system body when the lid is opened, but this does affect the feel of the keyboard in use; it's a little vague at times.

Powered by a 600MHz ultra-low-voltage Mobile Pentium III processor, dropping to 300MHz on battery power under SpeedStep power management, the PC-UM10 comes with 128MB of memory, which unfortunately cannot be upgraded. When running at 300MHz the PC-UM10 gives a respectable tested battery life of just under three hours, despite the relatively small size of the standard battery pack. A larger battery pack, capable of holding three times as much charge, is also available.

Storage is provided by a Hitachi 20GB hard disk, while the graphics are powered by a 4MB ATI Rage Mobility-M PCI chipset, which drives the 12.1-inch TFT display giving a maximum resolution of 1024 x 768 pixels with 32-bit colour depth. This display gives good contrast thanks to it's 'black panel' design.

Because the PC-UM10 is legacy-free due to its thinness, the floppy and CD-ROM drives are optional units costing 71 + VAT and 153 + VAT respectively. There is an optional docking bar available that adds serial and parallel ports, a VGA port and two USB ports for an additional 94 + VAT. One other slot that is missing is a Kensington lock slot for security.

Ports that are provided include one USB port, microphone and earphone sockets and a single Type II PC Card slot. Sharp says that it was too early to integrate Bluetooth capability into the PC-UM10, but that this would appear in later versions of the notebook.

The only features on the system body besides the keyboard and the Trackpad are the on/off button and the system LEDs, which gives the notebook a clean and uncluttered feel. The underside of the system features a hard reset switch. Our review model came with Windows 2000 with service pack 2 pre-installed but no software bundle was pre-loaded.

Sharp - PC-UM10 Muramasa features - Verdict

The Sharp PC-UM10 Muramasa certainly is the thinnest and one of the lightest notebooks around at the moment. It performs adequately and has a very reasonable battery life, but the lack of connectivity due to the thinness of the design and the additional cost of the floppy and CD-ROM drives may put some people off.

Sharp - PC-UM10 Muramasa price

1,599 + VAT

Sharp: 0800 138 8879

www.sharp.co.uk

Why is it Important to get the latest Windows XP Vista 7 Updates

If it seems like every time you turn around there is a brand new Windows update, then you're probably wondering how important they actually are. Despite what you may have heard, you require to update your Windows operating process whenever an update is made available.

Here are four reasons why you ought to update Windows on a regular basis.

One of the main issues with Vista concerns a major update. One of the service packs caused people issues. This made people leery of updating Windows in the future. However, the issue was solved & updating is highly recommended, even for Vista.

#1 The Windows Vista Operating process is Glitchy
Unless you have upgraded to Windows 7, the chances are your computer runs on a Windows Vista Operating process. In 2009, this applied to about 330 million computers. Therefore, it's safe to say plenty of people still use Vista regularly.

First, so plenty of more people use PCs than use Macs. about 2% - 20% (depending on who you ask) use Macs compared to the 80%-98% that use a computer. This automatically makes PCs more vulnerable to adware & viruses because they are a bigger target.

#2 Prevent adware & Viruses
a quantity of the things that makes Windows so great are also the things that make it vulnerable to adware & viruses.

Coding & programming issues also play a factor. In a nutshell, these issues stem from how Windows allows different programs to speak to each other. You see this in action when you copy something from MS Word & paste it in to MS Excel.

Microsoft makes use of the Windows Updates to close small backdoors & loopholes that hackers find. Since hackers are always looking for holes, Windows has to constantly close the holes.

#3 Speed Up Your computer
Since everyone wishes their computer to run faster, Windows puts out updates to make it run more effectively. Every time you install a brand new update, you're fundamentally speeding up your computer.

In the event you require your computer to run fast then:

Remember, in order to access the Microsoft Windows Update web-site, you require to be running the latest addition of web Explorer.

Install Windows Updates Promptly
Run anti-virus & anti-spyware on a every week basis
Use Windows Defragmenter on a every month basis
Run a registry cleaner on your computer on a every day basis
Use Windows Add/Remove feature to remove unused programs
Use Windows Disk Cleanup feature on a every month basis
Use Windows Error Checking Feature on a bi-monthly basis
Reduce the number of programs that load on start up

Despite the bad rap Windows updates have gotten over the past few years, the only way to fix Windows is with an update. It doesn't take much time & can save you lots of headaches in the future. As the elderly saying goes, "an ounce of prevention is worth a pound of cure." In the case of updates, this couldn't be more true.

How to Install a SCSI Device - part 1

This tutorial will take you through the steps involved in installing both internal and external SCSI devices - specifically a CD-ReWriter and scanner - covering each of the following:

installing the host adapter
configuring the devices
mounting the internal drive
making the connections
installing the associated software.

As with most specifications in the computer world, the original SCSI (pronounced scuzzy) specification was completed (in 1986) after work had already begun on a better version (SCSI-2). It was developed as a result of attempts by Shugart and NCR to develop a new interface for minicomputers. The basis of the interface was, and still is, the set of commands that control data transfer and communication among devices. The commands were the strength of SCSI, because they made the interface intelligent; but they were also its initial weakness, as there wasn't enough of a standard for the command set to be truly useful to device manufacturers. Consequently, in the mid-1980s, the Common Command Set (CCS) extension was developed to standardise SCSI commands.

The SCSI interface is a shared-bus configuration that supports a wide variety of peripherals, including HDDs, tape drives, optical drives, scanners, printers, and redundant arrays of independent disks (RAID) subsystems. The SCSI bus operates independently of the system CPU and the system bus through an integrated or plug-in host bus adapter (HBA).

The actual controllers are built into each SCSI device. They "chain" SCSI peripherals to the SCSI bus via the host adapter. Each device on the chain, including the host, must be identified by a unique ID number. One SCSI device must not use the same ID number as another, but they may be numbered non-sequentially. Most SCSI host adapters feature external and internal connectors, with the option for the chain to extend in either or both directions. There's no relationship between the IDs and the physical position on the bus, but both ends must be electrically "terminated" with resistors to prevent signal reflections and guarantee data integrity over long cable lengths. Termination comes in several varieties, from physical jumpers or plugs to software configurations.

The SCSI-1 standard allows for 8 devices to be connected to a single SCSI cable on a narrow bus configuration (8 data lines); SCSI-2 increases support to 16 devices on a wide bus configuration (16 data lines). New SCSI interfaces are backward compatible with most previous SCSI interfaces. SCSI devices of differing transfer speeds can coexist on the same SCSI bus. To guarantee compatibility and data reliability, transfer rates are negotiated between devices before data transfer is initiated.

Types of Customised USB Thumb Drives

Making sure that you keep your storage in the right place with the technology that you use. It can make the difference between completing a project on time or not. If you are looking for a way to do this with a different style, then you can begin by putting together customised USB thumb drives. This will not only help you in keeping your storage for your computer in one area, but will also allow you to do this with style.

Thumb drives are the same as other types of USB sticks. The difference is that the shape is close to the width of someone s thumb. This means that it will be skinnier and smaller than other types of USB drives. When you are putting together customised USB thumb drives, you will want to keep this idea in mind first so that you can put in the right lettering or graphic without taking up too much room or not looking right.

After you have the size measured out for the customised USB thumb drives, you can continue with determining how you want the personalised USB stick to look. When you begin to put this together you will want to start with defining the type of engraving you will get. The most common is a laser engraving which will leave a different colour from the laser as it moves into the material. You can also get insertions of words and graphics through more digital technology or engraving tools that are older. These will begin your specialized look with the USB drives.

Once you have decided on how you will personalise your USB drive you can continue with finding what you will be using the customised USB thumb drives for. This allows you to make even more out of the engraving you get. For instance, some engrave their USB drive for personal uses and to create a specific style to the drive. Others will use this as a promotional item for a business to help with marketing. There are also options for engraving the items for gifts for the office or for a school, all which create a different type of personalisation with the materials.

Making sure that you are able to keep in touch with different types of technology also allows you to use new fashion designs with your tools. Knowing how you can work with customised USB thumb drives to get the best look can help you for a variety of occasions, while giving you the best look to your drive. Finding the best way to get your name stamped into technology will also introduce you to better ways of saving while keeping style.

How to Install a Pentium 4 CPU - part 4

Removing the fan/heatsink assembly

It's unlikely that you'll ever need to remove the fan/heatsink assembly once fit. However, if you do, Intel offer the following advice on how to tackle this somewhat tricky procedure. First make the processor area accessible and unplug the processor fan heatsink power cable from the motherboard connector. Then open the clip levers one at a time, in opposing directions. Place the clip levers in the upward position. Use a #1, small flathead screwdriver to unhook the clip frame latches from the retention mechanism hooks, taking care not to damage the motherboard.
From the topside of the clip frame, insert the screwdriver in the small notch near the clip frame corner.
The screwdriver must be positioned carefully between the clip frame and the retention mechanism hook. Once in place, the screwdriver must be sitting on top of the clip frame latch.
Push down on the clip frame latch and simultaneously rotate the screwdriver towards the fan heatsink, to unhook the clip frame latch from the retention mechanism hook Repeat steps the procedure for each clip frame latch until all clip frame latches are no longer attached to the retention mechanism hooks.
To prevent the clip frame latches from re-attaching to the retention mechanism hooks:
First, unhook the clip frame latches on the same side of the fan heatsink (1 and 2). Once the first pair of latches are unhooked, use your free hand to hold the top of one of the clip frame corners (1), pulling the clip frame slightly upward to prevent the clip frame latches from re-attaching. Then, unhook the clip frame latch on the other side of the fan heatsink (3). Now, switch and hold the top of the other clip frame corner (2) with your free hand, again pulling the clip frame slightly upward to prevent re-attachment. Then, unhook the clip frame latch on the other side of the fan heatsink (4).
After all the clip frame latches are unhooked from the retention mechanism hooks, slowly remove the fan heatsink from the processor and retention mechanism. Slightly twisting the heatsink back and forth in the retention mechanism may make the heatsink easier to remove by lessening the surface tension force of thermal interface material between the processor and heatsink. Once the heatsink is removed, lift the processor socket handle to release the processor pins from the socket. Gently lift the processor out of the socket, taking care not to bend any of the processor pins.

Sorting Algorithms - Radix Sort part 1

Radix sort

A radix sort is an algorithm that can rearrange integer representations based on the processing of individual digits in such a way that the integer representations are eventually in either ascending or descending order. Integer representations can be used to represent things such as strings of characters (names of people, places, things, the words and characters that you are reading now, dates, etc.) and specially formatted floating point numbers as well as integers. So, anything which can be represented as an ordered sequence of integer representations can be rearranged to be in order by a radix sort.

Most digital computers internally represent all of their data as electronic representations of binary numbers, so processing the digits of integer representations by groups of binary digit representations is most convenient. Two classifications of radix sorts are least significant digit (LSD) radix sorts and most significant digit (MSD) radix sorts. LSD radix sorts process the integer representations starting from the least significant digit and move the processing towards the most significant digit. MSD radix sorts process the integer representations starting from the most significant digit and move the processing towards the least significant digit.

The integer representations that are processed by sorting algorithms are often called "keys," which can exist all by themselves or be associated with other data. LSD radix sorts typically use the following sorting order: short keys come before longer keys, and keys of the same length are sorted lexicographically. This coincides with the normal order of integer representations, such as the sequence 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. MSD radix sorts use lexicographic order, which is suitable for sorting strings, such as words, or fixed-length integer representations. A sequence such as "b, c, d, e, f, g, h, i, j, ba" would be lexicographically sorted as "b, ba, c, d, e, f, g, h, i, j". If lexicographic ordering is used to sort variable-length integer representations, then the representations of the numbers from 1 to 10 would be output as 1, 10, 2, 3, 4, 5, 6, 7, 8, 9, as if the shorter keys were left-justified and padded on the right with blank characters to make the shorter keys as long as the longest key for the purpose of determining sorted order.

Least significant digit radix sorts

A least significant digit (LSD) radix sort is a fast stable sorting algorithm which can be used to sort keys in lexicographic order. Keys may be a string of characters, or numerical digits in a given radix. The processing of the keys begins at the least significant digit, the rightmost digit, and proceeds to the most significant digit, the leftmost digit. The sequence in which digits are processed by a least significant digit (LSD) radix sort is the opposite of the sequence in which digits are processed by a most significant digit (MSD) radix sort.

A least significant digit (LSD) radix sort operates in O(nk) time, where n is the number of keys, and k is the average key length. You can get this performance for variable-length keys by grouping all of the keys that have the same length together and separately performing an LSD radix sort on each group of keys for each length, from shortest to longest, in order to avoid processing the whole list of keys on every sorting pass.

A radix sorting algorithm was originally used to sort punched cards in several passes. A computer algorithm was invented for radix sort in 1954 at MIT by Harold H. Seward. In many newer applications requiring super speeds and massive memory, the computer radix sort is an improvement on (slower) comparison sorts.

LSD radix sorts have resurfaced as an alternative to other high performance comparison-based sorting algorithms (like heapsort and mergesort) that require Ω(n log n) comparisons, where n is the number of items to be sorted. Comparison sorts can do no better than Ω(n log n) execution time but offer the flexibility of being able to sort with respect to more complicated orderings than a lexicographic one; however, this ability is of little importance in many practical applications.

Each key is first figuratively dropped into one level of buckets corresponding to the value of the rightmost digit of each key. Each bucket preserves the original order of the keys as the keys are dropped into each bucket. There is a one-to-one correspondence between the number of buckets and the number of values that can be represented by a digit. Then, the process repeats with the next neighboring digit until there are no more digits to process. In other words:

Take the least significant digit (or group of bits, both being examples of radices) of each key.
Group the keys based on that digit, but otherwise keep the original order of keys. (This is what makes the LSD radix sort a stable sort).
Repeat the grouping process with each more significant digit.

The sort in step 2 is usually done using bucket sort or counting sort, which are efficient in this case since there are usually only a small number of digits.

When an LSD radix sort processes keys which all have the same fixed length, then the upper bound of the execution time is O(n), where n is the number of keys to be sorted. When processing fixed-length keys, some implementations of LSD radix sorts are slower than O(n log n) comparison-based sorting algorithms, such as heap sort, unless a sufficiently large amount of input data is processed. What a sufficiently large amount of input data precisely is will vary from computer system to computer system and from implementation to implementation. If the keys used are short 2-byte integers, it is practical to complete the sorting with only two passes, processing 1 byte of each key per pass. In this case, and even when sorting 32-bit floating point numbers, radix sort can in practice be significantly faster than any other sorting algorithm. In one possible implementation of an LSD radix sort, variable length keys are padded with zero digits at the beginning of the keys to make all of the keys a fixed length, which requires O(NL) processing time, where N is the number of keys to be sorted and L is the length of the longest key.

One disadvantage of an LSD radix sort is that it does not run in place, which means that the keys or pointers to the keys must be temporarily stored outside of their original memory space during processing. O(n) additional memory space is needed to hold the keys or pointers to the keys. For fixed-length keys, another disadvantage of an LSD radix sort is that it requires one sorting pass over the input list for each digit in a key.

An example

Original, unsorted list:

170, 45, 75, 90, 2, 24, 802, 66

Sorting by least significant digit (1s place) gives:

170, 90, 2, 802, 24, 45, 75, 66

Notice that we keep 2 before 802, because 2 occurred before 802 in the original list, and similarly for 170 and 90.

Sorting by next digit (10s place) gives:

2, 802, 24, 45, 66, 170, 75, 90

Sorting by most significant digit (100s place) gives:

2, 24, 45, 66, 75, 90, 170, 802

It is important to realize that each of the above steps requires just a single pass over the data, since each item can be placed in its correct bucket without having to be compared with other items.

Some LSD radix sort implementations allocate space for buckets by first counting the number of keys that belong in each bucket before moving keys into those buckets. The number of times that each digit occurs is stored in an array. Consider the previous list of keys viewed in a different way:

170, 045, 075, 090, 002, 024, 802, 066

The first counting pass starts on the least significant digit of each key, producing an array of bucket sizes:

2 (bucket size for digits of 0: 170, 090)

2 (bucket size for digits of 2: 002, 802)

1 (bucket size for digits of 4: 024)

2 (bucket size for digits of 5: 045, 075)

1 (bucket size for digits of 6: 066)

A second counting pass on the next more significant digit of each key will produce an array of bucket sizes:

2 (bucket size for digits of 0: 002, 802)

1 (bucket size for digits of 2: 024)

1 (bucket size for digits of 4: 045)

1 (bucket size for digits of 6: 066)

2 (bucket size for digits of 7: 170, 075)

1 (bucket size for digits of 9: 090)

A third and final counting pass on the most significant digit of each key will produce an array of bucket sizes:

6 (bucket size for digits of 0: 002, 024, 045, 066, 075, 090)

1 (bucket size for digits of 1: 170)

1 (bucket size for digits of 8: 802)

At least one LSD radix sort implementation now counts the number of times that each digit occurs in each column for all columns in a single counting pass. Other LSD radix sort implementations allocate space for buckets dynamically as the space is needed.

Installing a PC Power Supply

Sometimes, despite all of our best intentions, good power supplies go bad. They are flash-fried by unexpected power surges or outages.

Some of them finally wear out after years of faithful service. Others are annihilated by dust, debris, or factory defects that went undetected for months, if not years. No matter how it dies, it ought to be buried, mourned, and then quickly replaced with a new version.

This task - replacing something with so many cables and connections - causes some PC users to run away, leaving their PC to suffer a miserable and untimely death. It seems like a big issue, but it really isn't. If you plan ahead and be sure to do the right things before you receive the new power supply, you can find one that will slide in and connect with minimal effort and little hassle on your part.

The first thing that you must do is confirm that it really is the power supply at fault. Troubleshooting can be done in just a few minutes and does not necessarily require a call to technical support. Several other potential problems should be checked first, even if it seems ridiculously simple. In many cases, the obvious is what is forgotten, and many dollars and man-hours of labor are wasted. Check the following so that it will not happen to you:

-Power cord running to the PC. Switch this out with the one running to your monitor (make sure that everything is turned off first). If your monitor comes on even with the switched cable, then the cord is not your problem. Switch them back and make sure that the monitor still powers up. If so, then you definitely save seven to twelve bucks on power cables.

-Power supplies running the computer. If, for example, you have everything connected through one power strip or ground-protection unit, ensure that all the other things plugged into it are functional. If your printer and speakers, for example, don't work, the problem might be with your power strip or protector, not the supply inside your computer. To test, plug the computer directly into a wall outlet that you know is functioning. If the computer works, get a new power strip. Don't leave it plugged directly into the wall because it is left an open target for power surges and outages.

-New components and other changes. Sometimes upgrading a piece of hardware, or doing work inside the computer, will mess things up. The solution is simple: either wait at least five minutes, with everything shut down (including the power strip - unplug it if you must) for the system to reset itself or remove any new components. If, for example, you just installed brand-new speakers and now the computer won't restart, detach them and allow the system to reset itself. This could fix the problem, though it will not necessarily make your new speakers work. If something like this is the case, you know that the power supply is all right, but you can contact the other component's maker for advice or replacement parts.

If these things aren't the problem, you can contact the PC manufacturer for troubleshooting tips. This might lead to something that isn't covered here, or it could reveal a problem that is unique to your PC's make and model. This is the best way to catch factory defects, glitches and other problems that your manufacturer might already know about, and can therefore fix. You should definitely use this option if your computer is still under any sort of warranty or guarantee.

If, however, you know that the power supply is the culprit and you cannot get warranty-covered work or parts to cover it, you can replace it yourself. This is not as dangerous as some might think, but there are still a couple of safety precautions that you must take.

First, never work with a power supply unless the computer is shut down. Leaving it connected is not a safe or smart option, so unplug it before you begin. Also: use anti-static pads, which you can get at any computer store, to disperse any static electricity that your body is generating as you walk across your carpet. If you don't want to spend five bucks on one of these, you can touch any metal object instead. You should also use de-magnetized tools every single time you approach your computer so that you do not flash-fry the motherboard or other components.

Secondly, you should never open up the power supply itself. It might be tempting to go in and have a look at the pretty wiring and other fun things inside it, but don't. Even if it's been dead and sitting unplugged for a month, it could still give you a nasty shock. You could also unintentionally spread static electricity to the rest of the computer and wreck other, important parts. It isn't worth the damage to yourself or your system, so leave it alone.

Before you can go shopping for another power supply, you need to figure out exactly what type you will need. Not all of them are the same. They carry different wattages, sizes, numbers of fans, and other options. Some have one power-plug port and others have two. Some have one fan and others have two. Some are larger and some are smaller. Needless to say, buying the wrong thing is going to make installation much harder and frustrating than it should be, as it will either not work at all or require one or more adaptors.

The easiest and fastest way to figure out what power supply you need is to contact your PC's manufacturer. If you have your model number ready, a representative should be able to give you part numbers. You should probably even be able to order a new unit right from the company, which can save a lot of time, a little money, and plenty of frustration.

If talking on the phone isn't your idea of a great time, visit the maker's Web site if you can get online. Most people have access to more than one computer, so even if the one you're trying to fix is dead there is probably another way to access the Internet. If nothing else, you can post to computer-geek-type forums that might have answers.

Once you've figured out exactly what you need, you can place the order. Once it arrives, set up a work area that is free of dust and other debris. It should also be as quiet as possible so that you can concentrate: some of the things that you will disconnect and hook up are very small and difficult to reach, so those with short tempers and little patience for this sort of thing will need every possible advantage. If you're the sort of person who likes relaxing music while you work, put on a soft-rock album and go to it.

The first thing that you should do is disconnect all the other stuff that's plugged into your computer. This includes the monitor and keyboard as well as flash drives, external devices and even the mouse. The less that you have to work around, the easier this installation will go for you.

Remove the computer's case cover. In newer models, this is usually a sliding panel on the side. In older computers, it requires you to remove a few bolts, usually located on the back of the case. If you remove bolts or screws, put them aside where you will not unintentionally knock them onto the floor and potentially lose them forever.

Your power supply is the large, vented box toward the back. It's where you plug in the power cable from the surge protector to the back of your computer. It should have several bolts or screws to keep it in place. Some can be accessed from outside the case: look on the back and remove the screws surrounding the fan. You should also make sure that any screws attaching the power supply to rails or brackets inside the computer are removed and safely stored out of your elbow's reach.

At this point, you should be able to slide the power supply backward a couple of inches and check the wiring. Because it is plugged in to several different internal components, it will not slide all the way out just yet. Do not succumb to the temptation to yank it out as fast and hard as you can; you'll only make things worse.

Now that you have a little room to work, you should remove a couple of wires at a time and attach the new supply's wires in their places. By doing it one or two at a time, you are sure to get everything back where it belongs instead of accidentally cross-wiring something.

In many cases, the connectors on your CD-ROM drive, disk drive and hard drive are large, bulky plastic pieces. They are very firmly seated and will probably require a little "oomph!" to remove. If this is the case, watch your hands. It's fairly common to bang your knuckles trying to yank these things out.

Hint: many power supplies are labeled by numbers or letters. Look for these on the plastic connectors that plug into the hard drive, CD-ROM, diskette drive if applicable, and CD burner. If your new power supply is the same make and model number as the old one, these should match up perfectly.

You might run into a confusing situation when you reattach the cables that run to the CD-ROM, hard drive, and other like hardware. This is because power supplies usually have two identical strings of cables: it's impossible to tell which one you should use to hook up all of those pieces of hardware. They both do the same job and have identical connectors, so it does not matter which one you connect. The important part is to pick one and stick with it instead of switching to the other string halfway through. Also: be sure to keep everything in the same order as it was when the old supply was used. If the CD-ROM drive, for example, is connected to number seven, then don't use connector number eight on the new one to hook it up unless you are told to do so by a qualified PC technician.

You might also run into problems when you try to remove smaller connectors located in various points on the motherboard. These connectors are often seated tightly on the motherboard and will require a little tugging. Be sure that you grasp the connector itself, not the wire, and pull evenly so that you don't unintentionally bend any prongs. If that still does not work, use a flashlight to look at the unit closely. You might find that there is a tab or other locking device to keep it in place, which can be unlocked with a fingernail.

Tip: when you attach the new power supply's cables, use even pressure to lock them into place. If they are not firmly seated, it won't work. You should also be sure that everything is lined up before you start pushing it in. Sometimes the connectors are tiny, three- or four-prong devices that are easily misaligned, which can lead to serious problems if you accidentally break one of them off.

You probably will not use every single cable or connector on the new power supply. In fact, you might find some odd-shaped connectors that don't seem to attach to anything that you've ever seen inside a computer. Both of these instances are okay as long as you use rubber bands to tie them together and store them in a safe location. You don't want them to interfere with any other operations or dangle in the way of anything.

Tip: leave them attached to the power supply. If you cut them off, you will have live wires hanging inside your computer, which can be dangerous. Besides which, you might need those extra connections someday.

Once all of your connectors are hooked up, slide the new power supply into place and plug it in. You shouldn't bother screwing everything back in and putting the case back together just yet. Now you can plug in the keyboard and mouse so that you can reboot the computer. If it works, shut it down and put the screws into the new power supply, then reattach the cover and enjoy life with a new power supply.

Once the computer is re-booted again, you should enjoy a frustration-free life with the new power supply. Dispose of the old one properly by taking it to a computer-recycling center, and keep any leaflets or warranty information that came with your new unit.

If, on the other hand, nothing works, you should contact technical support for advice. If this isn't your idea of fun, consult a computer-savvy friend or one of the numerous home-consultation/repair services listed in your telephone book.

Capacity and Performance of a Hard Disk

A typical desktop machine will have a hard disk with a capacity of between 10 and 40 gigabytes. Data is stored onto the disk in the form of files. A file is simply a named collection of bytes. The bytes might be the ASCII codes for the characters of a text file, or they could be the instructions of a software application for the computer to execute, or they could be the records of a data base, or they could be the pixel colors for a GIF image. No matter what it contains, however, a file is simply a string of bytes. When a program running on the computer requests a file, the hard disk retrieves its bytes and sends them to the CPU one at a time.

There are two ways to measure the performance of a hard disk:

Data rate - The data rate is the number of bytes per second that the drive can deliver to the CPU. Rates between 5 and 40 megabytes per second are common.

Seek time - The seek time is the amount of time between when the CPU requests a file and when the first byte of the file is sent to the CPU. Times between 10 and 20 milliseconds are common.

The other important parameter is the capacity of the drive, which is the number of bytes it can hold.

Inside: Electronics Board

The best way to understand how a hard disk works is to take a look inside. (Note that OPENING A HARD DISK RUINS IT, so this is not something to try at home unless you have a defunct drive.)

Here is a typical hard-disk drive:

It is a sealed aluminum box with controller electronics attached to one side. The electronics control the read/write mechanism and the motor that spins the platters. The electronics also assemble the magnetic domains on the drive into bytes (reading) and turn bytes into magnetic domains (writing). The electronics are all contained on a small board that detaches from the rest of the drive:

Inside: Beneath the Board

Underneath the board are the connections for the motor that spins the platters, as well as a highly-filtered vent hole that lets internal and external air pressures equalize:

Removing the cover from the drive reveals an extremely simple but very precise interior:

In this picture you can see:

The platters - These typically spin at 3,600 or 7,200 rpm when the drive is operating. These platters are manufactured to amazing tolerances and are mirror-smooth (as you can see in this interesting self-portrait of the author... no easy way to avoid that!).

The arm - This holds the read/write heads and is controlled by the mechanism in the upper-left corner. The arm is able to move the heads from the hub to the edge of the drive. The arm and its movement mechanism are extremely light and fast. The arm on a typical hard-disk drive can move from hub to edge and back up to 50 times per second -- it is an amazing thing to watch!

Inside: Platters and Heads

In order to increase the amount of information the drive can store, most hard disks have multiple platters. This drive has three platters and six read/write heads:

The mechanism that moves the arms on a hard disk has to be incredibly fast and precise. It can be constructed using a high-speed linear motor.

Many drives use a "voice coil" approach -- the same technique used to move the cone of a speaker on your stereo is used to move the arm.

Storing the Data

Data is stored on the surface of a platter in sectors and tracks. Tracks are concentric circles, and sectors are pie-shaped wedges on a track, like this:

A typical track is shown in yellow; a typical sector is shown in blue. A sector contains a fixed number of bytes -- for example, 256 or 512. Either at the drive or the operating system level, sectors are often grouped together into clusters.

The process of low-level formatting a drive establishes the tracks and sectors on the platter. The starting and ending points of each sector are written onto the platter. This process prepares the drive to hold blocks of bytes. High-level formatting then writes the file-storage structures, like the file-allocation table, into the sectors. This process prepares the drive to hold files.

Graph Data Structures - PHIGS and Databases

PHIGS

PHIGS was the first commercial scene-graph specification, and became an ANSI standard in 1988. Disparate implementations were provided by Unix hardware vendors. The "HOOPS 3D Graphics System" appears to have been the first commercial scene graph library provided by a single software vendor. It was designed to run on disparate lower-level 2D and 3D interfaces, with the first major production version (v3.0) completed in 1991. Shortly thereafter, Silicon Graphics released IRIS Inventor 1.0 (1992), which was a scene-graph built on top of the IRIS GL 3D API. It was followed up with Open Inventor in 1994, a portable scene graph built on top of OpenGL. More 3D scenegraph libraries can be found in Category:3D Scenegraph APIs.

Database

In computing, a database can be defined as a structured collection of records or data that is stored in a computer so that a program can consult it to answer queries. The records retrieved in answer to queries become information that can be used to make decisions. The computer program used to manage and query a database is known as a database management system (DBMS). The properties and design of database systems are included in the study of information science.

The term "database" originated within the computing discipline. Although its meaning has been broadened by popular use, even to include non-electronic databases, this article is about computer databases. Database-like records have been in existence since well before the industrial revolution in the form of ledgers, sales receipts and other business related collections of data.

The central concept of a database is that of a collection of records, or pieces of knowledge. Typically, for a given database, there is a structural description of the type of facts held in that database: this description is known as a schema. The schema describes the objects that are represented in the database, and the relationships among them. There are a number of different ways of organizing a schema, that is, of modeling the database structure: these are known as database models (or data models). The model in most common use today is the relational model, which in layman's terms represents all information in the form of multiple related tables each consisting of rows and columns (the true definition uses mathematical terminology). This model represents relationships by the use of values common to more than one table. Other models such as the hierarchical model and the network model use a more explicit representation of relationships.

The term database refers to the collection of related records, and the software should be referred to as the database management system or DBMS. When the context is unambiguous, however, many database administrators and programmers use the term database to cover both meanings.

Many professionals consider a collection of data to constitute a database only if it has certain properties: for example, if the data is managed to ensure its integrity and quality, if it allows shared access by a community of users, if it has a schema, or if it supports a query language. However, there is no agreed definition of these properties.

Database management systems are usually categorized according to the data model that they support: relational, object-relational, network, and so on. The data model will tend to determine the query languages that are available to access the database. A great deal of the internal engineering of a DBMS, however, is independent of the data model, and is concerned with managing factors such as performance, concurrency, integrity, and recovery from hardware failures. In these areas there are large differences between products.

History

The earliest known use of the term 'data base' was in July 1973, when the System Development Corporation sponsored a symposium under the title Development and Management of a Computer-centered Data Base. Database as a single word became common in Europe in the early 1970s and by the end of the decade it was being used in major American newspapers. (Databank, a comparable term, had been used in the Washington Post newspaper as early as 1966.)

The first database management systems were developed in the 1960s. A pioneer in the field was Charles Bachman. Bachman's early papers show that his aim was to make more effective use of the new direct access storage devices becoming available: until then, data processing had been based on punched cards and magnetic tape, so that serial processing was the dominant activity. Two key data models arose at this time: CODASYL developed the network model based on Bachman's ideas, and (apparently independently) the hierarchical model was used in a system developed by North American Rockwell, later adopted by IBM as the cornerstone of their IMS product. While IMS along with the CODASYL IDMS were the big, high visibility databases developed in the 1960's, several others were also born in that decade, some of which have a significant installed base today. Two worthy of mention are the PICK and MUMPS databases, with the former developed originally as an operating system with an embedded database and the latter as a programming language and database for the development of data-based software.

The relational model was proposed by E. F. Codd in 1970. He criticized existing models for confusing the abstract description of information structure with descriptions of physical access mechanisms. For a longwhile, however, the relational model remained of academic interest only. While CODASYL products (IDMS) and network model products (IMS) were conceived as practical engineering solutions taking account of the technology as it existed at the time, the relational model took a much more theoretical perspective, arguing (correctly) that hardware and software technology would catch up in time. Among the first implementations were Michael Stonebraker's Ingres at Berkeley, and the System R project at IBM. Both of these were research prototypes, announced during 1976. The first commercial products, Oracle and DB2, did not appear until around 1980. The first successful database product for microcomputers was dBASE for the CP/M and PC-DOS/MS-DOS operating systems.

During the 1980s, research activity focused on distributed database systems and database machines, but these developments had little effect on the market. Another important theoretical idea was the Functional Data Model, but apart from some specialized applications in genetics, molecular biology, and fraud investigation, the world took little notice.

In the 1990s, attention shifted to object-oriented databases. These had some success in fields where it was necessary to handle more complex data than relational systems could easily cope with, such as spatial databases, engineering data (including software engineering repositories), and multimedia data. Some of these ideas were adopted by the relational vendors, who integrated new features into their products as a result. The 1990s also saw the spread of Open Source databases, such as PostgreSQL and MySQL.

In the 2000s, the fashionable area for innovation is the XML database. As with object databases, this has spawned a new collection of startup companies, but at the same time the key ideas are being integrated into the established relational products. XML databases aim to remove the traditional divide between documents and data, allowing all of an organization's information resources to be held in one place, whether they are highly structured or not.

Database models

Various techniques are used to model data structure. Most database systems are built around one particular data model, although it is increasingly common for products to offer support for more than one model. For any one logical model various physical implementations may be possible, and most products will offer the user some level of control in tuning the physical implementation, since the choices that are made have a significant effect on performance. An example of this is the relational model: all serious implementations of the relational model allow the creation of indexes which provide fast access to rows in a table if the values of certain columns are known.

Flat model

This may not strictly qualify as a data model, as defined above. The flat (or table) model consists of a single, two-dimensional array of data elements, where all members of a given column are assumed to be similar values, and all members of a row are assumed to be related to one another.

Hierarchical model

In a hierarchical model, data is organized into a tree-like structure, implying a single upward link in each record to describe the nesting, and a sort field to keep the records in a particular order in each same-level list.

Relational model

Three key terms are used extensively in relational database models: relations, attributes, and domains. A relation is a table with columns and rows. The named columns of the relation are called attributes, and the domain is the set of values the attributes are allowed to take.

The basic data structure of the relational model is the table, where information about a particular entity (say, an employee) is represented in columns and rows (also called tuples). Thus, the "relation" in "relational database" refers to the various tables in the database; a relation is a set of tuples. The columns enumerate the various attributes of the entity (the employee's name, address or phone number, for example), and a row is an actual instance of the entity (a specific employee) that is represented by the relation. As a result, each tuple of the employee table represents various attributes of a single employee.

All relations (and, thus, tables) in a relational database have to adhere to some basic rules to qualify as relations. First, the ordering of columns is immaterial in a table. Second, there can't be identical tuples or rows in a table. And third, each tuple will contain a single value for each of its attributes.

A relational database contains multiple tables, each similar to the one in the "flat" database model. One of the strengths of the relational model is that, in principle, any value occurring in two different records (belonging to the same table or to different tables), implies a relationship among those two records. Yet, in order to enforce explicit integrity constraints, relationships between records in tables can also be defined explicitly, by identifying or non-identifying parent-child relationships characterized by assigning cardinality (1:1, (0)1:M, M:M). Tables can also have a designated single attribute or a set of attributes that can act as a "key", which can be used to uniquely identify each tuple in the table.

A key that can be used to uniquely identify a row in a table is called a primary key. Keys are commonly used to join or combine data from two or more tables. For example, an Employee table may contain a column named Location which contains a value that matches the key of a Location table. Keys are also critical in the creation of indexes, which facilitate fast retrieval of data from large tables. Any column can be a key, or multiple columns can be grouped together into a compound key. It is not necessary to define all the keys in advance; a column can be used as a key even if it was not originally intended to be one.

Relational operations

Users (or programs) request data from a relational database by sending it a query that is written in a special language, usually a dialect of SQL. Although SQL was originally intended for end-users, it is much more common for SQL queries to be embedded into software that provides an easier user interface. Many web sites, such as Wikipedia, perform SQL queries when generating pages.

In response to a query, the database returns a result set, which is just a list of rows containing the answers. The simplest query is just to return all the rows from a table, but more often, the rows are filtered in some way to return just the answer wanted. Often, data from multiple tables are combined into one, by doing a join. There are a number of relational operations in addition to join.

Normal Forms

Relations are classified based upon the types of anomalies to which they're vulnerable. A database that's in the first normal form is vulnerable to all types of anomalies, while a database that's in the domain/key normal form has no modification anomalies. Normal forms are hierarchical in nature. That is, the lowest level is the first normal form, and the database cannot meet the requirements for higher level normal forms without first having met all the requirements of the lesser normal forms.

Object database models

In recent years, the object-oriented paradigm has been applied to database technology, creating a new programming model known as object databases. These databases attempt to bring the database world and the application programming world closer together, in particular by ensuring that the database uses the same type system as the application program. This aims to avoid the overhead (sometimes referred to as the impedance mismatch) of converting information between its representation in the database (for example as rows in tables) and its representation in the application program (typically as objects). At the same time, object databases attempt to introduce the key ideas of object programming, such as encapsulation and polymorphism, into the world of databases.

A variety of these ways have been tried for storing objects in a database. Some products have approached the problem from the application programming end, by making the objects manipulated by the program persistent. This also typically requires the addition of some kind of query language, since conventional programming languages do not have the ability to find objects based on their information content. Others have attacked the problem from the database end, by defining an object-oriented data model for the database, and defining a database programming language that allows full programming capabilities as well as traditional query facilities.

Post-relational database models

Several products have been identified as post-relational because the data model incorporates relations but is not constrained by the Information Principle, requiring that all information is represented by data values in relations. Products using a post-relational data model typically employ a model that actually pre-dates the relational model. These might be identified as a directed graph with trees on the nodes.

Examples of models that could be classified as post-relational are PICK aka MultiValue, and MUMPS, aka M.

CPU Technology - part 9

Mobile Athlon 4

Emulating Intel's practice of introducing new technology in lower volume market sectors first, AMD's first deployment of the Palomino core was in their Mobile Athlon 4 processor. At the time it appeared that the "Athlon 4" nomenclature had more than a little to do with Intel's multi-million dollar "Pentium 4" marketing campaign. In the event, it was used exclusively for AMD's mobile CPUs, with the desktop versions of the Palomino adopting the "XP" branding.

The Mobile Athlon 4 has all the same enhancements as the desktop Palomino core:

an improved hardware data prefetch mechanism
enhancements to the processor's data TLB
full support for Intel's SSE instruction set
reduced power consumption
implementation of a thermal diode to monitor processor temperature.

Like previous CPUs the Mobile Athlon 4 also features AMD's PowerNow! technology, which allows a processor to dynamically change its clock speed and operating voltage depending on the prevailing application demands. Appropriate BIOS and chipset support is necessary for PowerNow! to be taken advantage of.

By the spring of 2002 the fastest available Mobile Athlon 4 CPU was the Model 1600+.

PowerNow!

PowerNow! is effectively AMD's version of Intel's SpeedStep technology. The premise is a simple one: some applications require less processing power than others. Word processing, for example, consumes relatively few processor cycles, whereas playing a DVD, photo editing or running other media-rich applications requires more processor cycles to deliver a responsive level of performance.

AMD PowerNow! controls the level of processor performance automatically, dynamically adjusting the operating frequency and voltage many times per second, according to the task at hand. When an application does not require full performance, significant amounts of power can be saved. The Mobile Athlon 4 implementation of the technology allows for a total of 32 speed/voltage steps between 500MHz at 1.2V and the maximum clock speed of the processor. Realistically, in normal usage only between 4 and 8 steps are likely to be used. The only user-noticeable effect of PowerNow! technology is extended battery life.

Mobile Pentium 4

Intel's Pentium 4-M CPU came to market in the spring of 2002 at a clock frequency of up to 1.7GHz. The CPU's Micro FCPGA packaging technology results in the CPU using less power in both the performance and battery optimised modes, making it run cooler and thereby allowing the processor to fit into smaller notebook form factors.

On the average a Mobile Pentium 4-M chip uses two watts of power. It achieves this by dropping to an operating voltage of less than 1V whenever possible and ramping up to its maximum 1.3V only when peak performance is necessary. This real-time dynamic switching of voltage levels is one of the techniques by which battery life is extended. Another is the dynamic power management's Deeper Sleep Alert State which allows further power savings to be made during periods of inactivity - which can be as brief as microseconds between key strokes.

With Tualatin-based Pentium III-M and Mobile Celeron CPUs offering a wide range of price/performance points across the entire range of notebook form factors and Intel having already announced that it expects its next generation Mobile Pentium 4 processor - codenamed "Banias" and expected in the first half of 2003 - to become the mainstay in the notebook sector going forward, it remains to be seen how big an impact the Pentium 4-M will have.

Billed as Intel's "first chip designed from the ground up to power notebooks", Banias - named after an archaeological site in the Middle East - will be fundamentally different from other Intel notebook chips, having an architecture that is distinct from that of desktop CPUs and that is designed to support more power conservation features than previous generations of mobile chips.

Creative - DAP Jukebox Review

Creative's DAP is a different creature from the rest of the MP3 devices in this group. It's an MP3 jukebox and its main advantage over a conventional player is that you can record over 100 hours of audio (around 150 albums worth) on it at one time - more than many people's entire music collections.

DAP uses a 6GB hard drive to hold and play back MP3 or WMA format music files. This has two immediate consequences - three if you include the price. First, the DAP player is much bigger than most MP3 players, close to the size of a portable CD player. Second, it needs reasonably careful handling; using a hard drive, with its delicate moving parts, instead of solid state memory, means you should handle it with the same care as a notebook. Finally, it costs nearly as much as two conventional MP3 players.

The device is easy to use, with an eight-line, back-lit LCD display showing details of your music. You can set up your own playlists and view track names and artist details using an array of 11 buttons on its top surface.

The PC-based software consists of Play Center, which converts CD tracks, manages your music and downloads it from Internet and to the DAP, Lava, which displays 3D visuals for your music, and MediaRing Talk which, rather incongruously, is an Internet phone utility.

Overall, this is a great system for those with a lot of music and no desire to go jogging. Treat it gently and you can take all your music with you.

Creative - DAP Jukebox price

379 inc. VAT

Creative: 01189 344322

www.creativejukebox.com

Sorting Algorithms - Heapsort

Heapsort

A run of the heapsort algorithm sorting an array of randomly permuted values. In the first stage of the algorithm the array elements are reordered to satisfy the heap property. Before the actual sorting takes place, the heap tree structure is shown briefly for illustration.

Heapsort is one of the best general- purpose sorting algorithms, a comparison sort and part of the selection sort family. Although somewhat slower in practice on most machines than a good implementation of quicksort, it has the advantages of worst-case O (n log n) runtime. Heapsort is an in-place algorithm and is not a stable sort.

Overview

One simple way to sort a list of objects is to use a heap data structure. All elements to be sorted are inserted into a heap, and the heap organizes the elements added to it in such a way that either the largest value (in a max-heap) or the smallest value (in a min-heap) can be quickly extracted. Moreover, because this operation preserves the heap's structure, the largest/smallest value can be repeatedly extracted until none remain. This gives us the elements in order.

In doing so, the only extra space required is that needed to store the heap. In order to achieve constant space overhead, we use a trick: we store a binary heap (or alternatively, a heap with more than two children) inside the part of the input array which has not yet been sorted. (The structure of this heap is described at Binary heap: Heap implementation.) Heapsort makes use of two standard heap operations: insertion and root deletion. Each time we delete (extract) the maximum, we place it in the last location of the array not yet occupied, and use the remaining prefix of the array as a heap holding the remaining unsorted elements:

Heap of remaining unsorted elements ||

Sorted elements

Variations

The most important variation to the simple variant is an improvement by R.W.Floyd which gives in practice about 25% speed improvement by using only one comparison in each siftup run which then needs to be followed by a siftdown for the original child; moreover it is more elegant to formulate. Heapsort's natural way of indexing works on indices from 1 up to the number of items. Therefore the start address of the data should be shifted such that this logic can be implemented avoiding unnecessary +/- 1 offsets in the coded algorithm.

Although not widely known, it is possible to define a ternary heapsort which uses a ternary heap instead of a binary heap; that is, each element in the heap has three children. Ternary heapsort is somewhat more complicated to program, but it is potentially faster. Each step in the shift operation of a ternary heap requires three comparisons and one swap, whereas in a binary heap two comparisons and one swap are required. The ternary heap can do two steps in less time than the binary heap requires for three steps. But two steps of a ternary tree multiply the index by a factor of 9, which is more than the factor 8 of three binary steps. Ternary heapsort is about 12% faster than the simple variant of binary heapsort.

The smoothsort sorting algorithm is a variation of heapsort developed by Edsger Dijkstra in 1981. Like heapsort, smoothsort's upper bound is O (n log n). The advantage of smoothsort is that it comes closer to O(n) time if the input is already sorted to some degree, whereas heapsort averages O(n log n) regardless of the initial sorted state. Due to its complexity, smoothsort is rarely used.

Comparison with other sorts

Heapsort primarily competes with quicksort, another very efficient general purpose nearly-in-place comparison-based sort algorithm.

Quicksort is typically somewhat faster, due to better cache behavior and other factors, but the worst-case running time for quicksort is O(n²), which is unacceptable for large data sets and can be deliberately triggered given enough knowledge of the implementation, creating a security risk. See quicksort for a detailed discussion of this problem, and possible solutions.

The quicksort algorithm also requires Ω(log n) extra storage space, making it not a strictly in-place algorithm. This typically does not pose a problem except on the smallest embedded systems, or on systems where memory allocation is highly restricted. Constant space (in-place) variants of quicksort are possible to construct, but are rarely used in practice due to their extra complexity.

Thus, because of the O(n log n) upper bound on heapsort's running time and constant upper bound on its auxiliary storage, embedded systems with real-time constraints or systems concerned with security often use heapsort.

Heapsort also competes with merge sort, which has the same time bounds, but requires Ω(n) auxiliary space, whereas heapsort requires only a constant amount. Heapsort also typically runs more quickly in practice on machines with small or slow data caches. On the other hand, merge sort has several advantages over heapsort:

Like quicksort, merge sort on arrays has considerably better data cache performance, often outperforming heapsort on a modern desktop PC, because it accesses the elements in order.
Merge sort is a stable sort.
Merge sort parallelises better; the most trivial way of parallelising merge sort achieves close to linear speedup, while there is no obvious way to parallelise heapsort at all.
Merge sort can be easily adapted to operate on linked lists and very large lists stored on slow-to-access media such as disk storage or network attached storage. Heapsort relies strongly on random access, and its poor locality of reference makes it very slow on media with long access times.

Pseudocode

The following is the "simple" way to implement the algorithm, in pseudocode, where swap is used to swap two elements of the array. Notice that the arrays are zero based in this example.

 function heapSort(a, count) is

     input:  an unordered array a of length count

     (first place a in max-heap order)

     heapify(a, count)

     end := count - 1

     while end > 0 do

         (swap the root(maximum value) of the heap with the last element of the heap)

         swap(a[end], a[0])

         (decrease the size of the heap by one so that the previous max value will

         stay in its proper placement)

         end := end - 1

         (put the heap back in max-heap order)

         siftDown(a, 0, end)

 function heapify(a,count) is

     (start is assigned the index in a of the last parent node)

     start := count 2 - 1

     while start ≥ 0 do

         (sift down the node at index start to the proper place such that all nodes below

          the start index are in heap order)

         siftDown(a, start, count-1)

         start := start - 1

     (after sifting down the root all nodes/elements are in heap order)

 function siftDown(a, start, end) is

     input:  end represents the limit of how far down the heap

                   to sift.

     root := start

     while root * 2 + 1 ≤ end do          (While the root has at least one child)

         child := root * 2 + 1            (root*2+1 points to the left child)

         (If the child has a sibling and the child's value is less than its sibling's...)

         if child < end and a[child] < a[child + 1] then

             child := child + 1           (... then point to the right child instead)

         if a[root] < a[child] then       (out of max-heap order)

             swap(a[root], a[child])

             root := child                (repeat to continue sifting down the child now)

         else

             return

The heapify function can be thought of as successively inserting into the heap and sifting up. The two versions only differ in the order of data processing. The above heapify function starts at the bottom and moves up while sifting down (bottom-up). The following heapify function starts at the top and moves down while sifting up (top-down).

 function heapify(a,count) is

     (end is assigned the index of the first (left) child of the root)

     end := 1

     while end < count

         (sift up the node at index end to the proper place such that all nodes above

          the end index are in heap order)

         siftUp(a, 0, end)

         end := end + 1

     (after sifting up the last node all nodes are in heap order)

 function siftUp(a, start, end) is

     input:  start represents the limit of how far up the heap to sift.

                   end is the node to sift up.

     child := end

     while child > start

         parent := ⌊(child - 1) 2⌋

         if a[parent] < a[child] then (out of max-heap order)

             swap(a[parent], a[child])

             child := parent (repeat to continue sifting up the parent now)

         else

             return

C-code

Below is an implementation of the "standard" heapsort (also called bottom-up-heapsort). It is faster on average (see Knuth. Sec. 5.2.3, Ex. 18) and even better in worst-case behavior (1.5n log n) than the simple heapsort (2n log n). The sift_in routine is first a sift_up of the free position followed by a sift_down of the new item. The needed data-comparison is only in the macro data_i_LESS_THAN_ for easy adaption.

/*  Heapsort based on ideas of J.W.Williams/R.W.Floyd/S.Carlsson  */

#define  data_i_LESS_THAN_(other)   (data[i] < other)

#define  MOVE_i_TO_free  { data[free]=data[i];  free=i; }

void sift_in(unsigned count, SORTTYPE *data, unsigned free, SORTTYPE next)

   unsigned  i;

   /** sift up the free node **/

   for (i=2*free;i<count;i+=i)

   {  if (data_i_LESS_THAN_(data[i+1]))  i++;

      MOVE_i_TO_free

   /* special case in sift up if the last inner node has only 1 child */

   if (i==count)

      MOVE_i_TO_free

   /** sift down the new item next **/

   while((i=free/2)  &&  data_i_LESS_THAN_(next))

      MOVE_i_TO_free

   data[free] = next;

void heapsort(unsigned count, SORTTYPE *data)

   unsigned  j;

   if (count <= 1)  return;

   data-=1;   /* map addresses to indices 1 til count  */

   /** build the heap structure **/

   for(j=count/2;j;j-=1)

   {  SORTTYPE  next = data[j];

      sift_in(count, data, j, next);

   /** search next by next remaining extremal element **/

   for(j=count-1;j;j-=1)

   {  SORTTYPE  next = data[j+1];

      data[j+1] = data[1];   /* extract extremal element from the heap */

      sift_in(j, data, 1, next);

Are You Safe Online?

Minimizing the risks related to the Internet security is of primary concern for any online business site. Internet security is very important and must be guarded severely at all costs. Minimizing the risks related to online security will ensure that you will be able to attract many customers to your online sites. Many security measures can be installed in an online site for lessening the risk of Internet security.

If the customers are not sure about the security of their personal details and financial statements, they will never conduct online business. Internet privacy security is very important for any online business site.

Internet Computer privacy is at risk due to the presence of different elements. The presence of spyware is one factor of risk for Internet privacy security. The spyware that is present in your computer can track your online behavior. Spyware software is enabled with the advanced features that allow the spyware manufacturers to surreptitiously track the actions of a computer user. The information gathered through this process can be used to commit frauds and other illegal activities.

Where there is data, there is a threat to its security. More so for very large organizations that need to be ready with disaster recovery measures and return to work as quickly as possible. Maybe you have firewalls, a regularly up to date anti virus program to protect your system and other software that detects spy ware and so on. But time is money. With the RollBack Rx system restore software, which also prevents data loss, you save both! As a snapshot-based approach this software helps you manage the configuration of your systems and lets you save money on PC support. This naturally results in minimizing downtime.

All Microsoft Windows based PCs support RollBack Rx software. It operates at the sector level and enables both remote and local update. It helps in patch management as well, making it faster and more effective since it has the ability to make a snapshot of the system before the patch was installed, which means making it possible to instantly RollBack to the pre-patch state.

Most computers have anti virus or spy ware protection installed in them. RollBack Rx is compatible with all anti-virus and anti-spy ware applications and software. You can just instruct your RollBack Rx to take a snapshot of your system before or after anti virus updates.

Imagine yourself in a situation where someone else is able to monitor every move that you make. This is a terrifying situation to face. The best way for you to escape such a situation is to install the best security features in your Computer. You will then be able to surf online peacefully without constantly worrying about your Internet privacy security.

Iomega - HipZip Review

Iomega is a late arrival at the MP3 ball, but its HipZip has a key extra. It stores its music files on removable, 8 Clik (sorry, Pocket Zip) disks. This means you can build up a stack of disks much more cheaply than using memory cards and leave files on disk, rather than having to download new music before every trip.

The HipZip is a chunky, well-designed unit which can easily be operated with your left hand. The menu system controls are on the right side, with playback controlled from four on its front panel. The menu system on the backlit display is straightforward and download is via USB, as it is with all five of these players.

The supporting PC software comprises MusicMatch and Iomega's Iomegaware. MusicMatch handles download of files from the Internet and converting them from CD, as well as copying them to your HipZip.

There are three hang-ups with the HipZip, which may slow its adoption. First, it costs a lot, not much less than the Creative DAP and 100 more than any of the other main contenders. Second, 8 per Pocket Zip disk may look cheap against memory cards, but it doesn't measure up against MiniDisc, where blanks cost around 1.50 each. Finally, if you want decent audio quality, a 40MB Pocket Zip disk only holds around half a typical album.

The HipZip has a lot of potential, but the player should cost no more than 199 and an 80MB Pocket Zip disk (Iomega's working on a larger capacity) should be no more than 3. Sales would then fly.

Iomega - HipZip price

290 inc. VAT

Iomega: 020 73659527

www.iomega.com/hipzip

Pine - D'Music Review

Hoorah! Finally we find an MP3 player that displays the track name on the LCD screen.

The D'Music player (an earlier version of which we've reviewed here) looks very similar to the Rio player. In terms of functionality it doesn't differ much either - there's random and A-B play, for example, alongside repeat play. But the casing is made out of a strange plastic that feels better to the touch.

Sound quality was also very good indeed, with the in-ear headphones producing a clear sound. We reckon that perhaps it wasn't quite as punchy and well-defined as the Rio, but it was close.

The usual three EQ modes are available and are accompanied by a frequency bar display on the LCD panel showing which parts of the sound are beefed-up. There's also an 'Ex-Bass' mode which effectively gives a MegaBass effect.

Like the Philex player, the D'Music player is able to record voice via a built-in microphone although, unlike the Philex machine, there's no line-in to record from an external source. Once again the recorded sound quality is poor although Pine claim that you will get around 2 hours and 15 minutes recording time before you fill the memory, which is not bad going.

The software lacks sparkle and has much of the rough and ready feel of the Philex player. The songs take a long time to transfer to the machine, too. Downloading eight or so songs takes a good fifteen minutes, whereas with the Rio 300 it takes around five. The Pine D'Music runs on two AAA batteries.

Pine - D'Music price

90 + VAT

Pine: 01908 218812

How to Install a Second Hard Disk - part 4

Configuring BIOS

Once the second hard drive is physically installed, you then need to let the computer's operating system and software know that it exists.

Insert the MS-DOS startup disk in your floppy disk drive and power on your PC. After the POST (Power On Self Test) process has started enter the system's CMOS setup routine as described in your system's documentation (normally by pressing the DEL, F1 or F2 key.

To have the BIOS automatically detect the new drive and set its parameters you need to enter the Standard CMOS Setup category of the BIOS Setup and ensure that both the Primary IDE Master and Primary IDE Slave are set to Auto to autodetect the drives on startup.

If your hard disks and system BIOS are fairly recent, it's likely that they'll provide support for the S.M.A.R.T hard disk capability. It's not vital to do this right now, but if you do intend to use it, you should enable it before too long.

Save the settings and exit the setup routine, allowing the system to boot from the startup disk.

S.M.A.R.T can usually be enabled via the Advanced BIOS Features category of the BIOS Setup.

It's origins date from 1992, when IBM began shipping 3.5-inch hard disk drives that could actually predict their own failure - an industry first. These drives were equipped with Predictive Failure Analysis (PFA), an IBM-developed technology that periodically measured selected drive attributes and sent a warning message when a predefined threshold is exceeded. Industry acceptance of PFA technology eventually led to S.M.A.R.T (Self-Monitoring, Analysis and Reporting Technology) becoming the industry-standard reliability prediction indicator for both IDE/ATA and SCSI hard disk drives.

Today all major hard disk drive manufacturers support S.M.A.R.T. It needs to be enabled in your system BIOS. When it is it will typically monitor the following:

Head flying height data
Throughput performance
Spin-up time
Re-allocated sector count
Seek error rate
Seek time performance
Spin try recount
Drive calibration retry count

S.M.A.R.T should be enabled when a hard disk drive is new since it is designed to monitor a hard disk drive over time and needs first to establish a baseline assessment of your drive's performance characteristics. When performance starts to drop below the average it has established for your drive, it will notify you of an impending hard drive failure.

A number of Windows-based utilities are available that effectively provide a GUI front end to S.M.A.R.T.

Partitioning the drive

If your second drive is a new, empty hard disk, you're going to have to first create a primary partition on the disk and then format a file system on that partition. If you're installing on a disk you've been using previously, you may want to delete it's existing partitions before creating new ones. Each allocated space on the hard disk is assigned a drive letter and the Fdisk utility may be used to create, change, delete, or display information about the current partitions on a hard disk. It allows you to specify partition sizes and to define which partition will be the active (boot) partition. Fdisk writes the partition table into the first sector of track zero of the partitionable disk. This partition table also contains the master boot block. When the machine is turned on, the ROM BIOS will read this master boot block and transfer control to it. The master boot block then finds out which partition is active, reads the boot code from that partition, and then transfers control to that boot code. FAT - the acronym stands for File Allocation Table - is a file system that was first introduced in 1981. Windows 98 supports both the FAT16 and FAT32 variants, and you need to decide which you are going to use before proceeding any further.
FAT16: The FAT16 file system has a maximum of 2 gigabytes (GB) for each allocated space or drive letter. For example, if you use the FAT16 file system and have a 6GB hard disk, you can have three drive letters (C, D, and E), each with 2GB of allocated space. The 2GB partition limit is imposed by the maximum number of clusters and the largest cluster size supported by the FAT file system. The FAT file system is limited to 65,525 clusters. The size of a cluster must be a power of 2 and less than 65,536 bytes - this results in a maximum cluster size of 32,768 bytes (32K). Multiplying number of clusters (65,525) by the maximum cluster size (32,768) equals 2GB. FAT32: Windows 95 OEM Service Release version 2 and later support drives larger than 2GB using the FAT32 file system. This offers the following enhancements over previous implementations of the FAT file system. FAT32 supports drives that are up to 2 terabytes (TB) in size and stores files on smaller sections of the hard disk than the FAT16 file system does. This results in more free space on the hard disk. FAT32 is also more robust, being less susceptible to a single point of failure than earlier version of the file system. The FAT32 file system does not support drives that are smaller than 512MB.
After the system has booted to your startup disk, proceed as follows:
1.	At the A:> prompt type fdisk and press Enter.
2.	If the hard disk is larger than 512 MB, you receive the following prompt:

3.	If you want to use the FAT32 file system, press Y, and then press Enter. If you want to use the FAT16 file system, press N, and then press Enter.
4.	After you press Enter, the Fdisk Options menu is displayed:

5.	Select option 5 so that you can switch to the newly installed D: drive:

6.	Enter 2 and press Esc to return to the FDISK Options.

7.	Enter 4 to remind yourself of the current information for the D: drive.

8.	Press Esc to return to the FDISK Options and select option 3 to delete existing partitions.

9.	When you've deleted all the existing partitions you require, return to the FDISK Options menu. Press 1 to select the Create DOS partition or Logical DOS Drive option:

10.	Press 1 to select the Create Primary DOS Partition option. After you press Enter, you receive the following prompt: Do you wish to use the maximum available size for primary DOS partition? Enter Y and Fdisk proceeds to allocate the whole disk to the partition.
Depending on its size, you may choose to divide your hard disk in multiple partitions. The precise manner in which you do this depends on your purpose in partitioning in the first place. For example, if your purpose is to create a dual-boot system, capable of running different operating systems, the method you use will be different from if you're using partitioning simply as an organisational and data management device.
There are a number of reasons why you may want to organise your hard disk into multiple partitions: Organisation: Partitions provide a higher level of organisation than is possible with folders and files alone. Flexibility: The ability to boot your machine to multiple operating systems - Windows 98 and Windows NT say - is best achieved via the use of separate primary partitions. Resiliency: The failure of a single partition won't necessarily render the entire system unusable. Security: The separation of data and software into different partitions can make for a simplified and more efficient security backup regime. Performance: Partitioning can benefit both general system performance and certain housekeeping tasks such as disk defragmentation. Efficiency: Use of multiple partitions can reduce cluster sizes and, in turn, wasted disk storage capacity. Convenience: Perhaps the most compelling reason of all is the degree to which the isolation of the operating system into a dedicated partition can simplify things when you find yourself having to perform a clean reinstallation of Windows! Assuming your system has only one physical hard disk drive, it will need to have at least one "primary" partition. A drive may actually have up to four primary partitions, but only one of these can be "active" at any given time. If you want to organise your disk into anything more than a single primary partition, you need to create an "extended" partition, which may then be sub-divided into a number of "logical DOS drives". A bootable operating system can only reside on a primary partition, and a in a typical single-drive system the partition will be the C: drive, with the logical DOS drives being assigned drive letters D:, E:, :F etc. An "extended" partition counts as one of a disk's four allowable primary partitions, and does not itself have a drive letter. Drive referencing can become confusing in a multiple hard disk system, since drive-letters are assigned to all primary partitions first. If you subsequently add a further hard disk to your system, you can avoid impact on your existing drive letters by not creating a primary partition on the new drive. but instead creating an extended partition - the size of the entire physical disk - and sub-dividing this into multiple Logical DOS drives.

Computer Warning: Precaution to Remember Before Working on Your

If you re going to open-up your personal computer on checking some computer hardware components or for cleaning-up the hardware you must have to take these some precautions I listed. Computer motherboards and components, such as sound card, video card, and memory, contain very delicate Integrated Circuit (IC) chips. To protect computers against damage from static electricity, Anyway for brief information on what static is, it s a major contributing factor in the breakdown of computers, eliminating the damage from ESD (Electrostatic Discharge) can save a lot of money. Here are some warnings you must remember and follow some precautions whenever you work on your computer.

1. Unplug your computer when working on the inside or well known inside of central processing unit (CPU). You must unplug the power cord to ensure that there is no power to the motherboard.
2. Capacitors can still store electric charge for a short from the time you turned off the power switch, so it's a wise to make is to wait a few minutes after pulling the plug before working on your PC.
3. Use a grounded wrist strap before handling computer components such as the video card, memory, hard disk, and etc. if you do not have one, touch both of your hands to a safety grounded object or to a metal object, such as the power supply case.
4. Hold components in both edges and try not to touch the IC chips, leads, capacitors, or circuitry as these are miniature electronic components and it may damage.
5. Place components on a grounded anti-static pad or on the bag that came with the components whenever the components are separated from the system. Remember, avoid dropping your hard disk in the surface or in the floor because cylinder of the hard disk is sensitive which may cause not to working at all.
6. Don t ever touch the non-serviceable. When you come across labels that say "No serviceable components inside" don't take it as a challenge because it s a serious statement. Remember some parts of a computer are just not meant to repaired which usually seen on the power supply.

Keep in mind that failure in protecting yourself can cause injuries and it can also damage your computer and the most common accident is erasing stored data (due crash board). These are simple to remember to protect yourself, software, hardware, and the most important to protect our precious stored data from our computer.

CPU Technology - part 2

Tillamook

Conspicuous by its absence from Intel's launch of MMX at the beginning of 1997 was a 200MHz version of the Pentium MMX for notebooks. This omission was addressed before the year was out, however, with the announcement of its latest mobile processor codenamed "Tillamook", after a small town in Oregon. The new processors were originally available at speeds of 200MHz and 233MHz - with a 266MHz version following early in 1998.

The Tillamook was one of the first processors to be built on an Intel-developed pop-out Mobile Module for notebooks, called MMO. The module held the processor, 512KB of secondary cache, a voltage regulator to buffer the processor from higher voltage components, a clock, and the new 430TX PCI Northbridge chipset. It was connected to the motherboard by a single array of 280 pins, similar to the Pentium II's SEC cartridge.

On the chip itself, the biggest difference was in the 0.25-micron process: down from 0.35 microns in the older-style mobile Pentium chips, and much smaller than the 0.35-micron process used on desktop Pentiums. The lower micron value had a knock-on effect on the speed and the voltage.

As the transitions (the electrical pulses of ones and zeros) occurring on the processor are physically closer together, the speed is automatically increased. Intel claimed a performance increase of 30%. As the transitions are closer together, the voltage has to be reduced to avoid damage caused by a strong electrical field. Previous versions of the Intel mobile Pentium had 2.45V at the core but on Tillamook this was reduced to 1.8V. A voltage regulator was needed to protect the chip from the PCI bus and the memory bus, both of which ran at 3.3V.

The mobile 200MHz and 233MHz CPUs generated 3.4 watts and 3.9 watts TDP (thermal design power) typical respectively. These improvements represented nearly a 50% decrease in power consumption over the previous generation 166MHz mobile Pentium processor with MMX technology. This was just as well, as many of the notebooks using this chip were driving energy-sapping 13.3in and 14.1in screens intended for graphics-intensive applications. On the plus side, a lower voltage also meant lower heat emissions - a real problem with desktop chips.

The processor was sold to manufacturers either on its own in a Tape Carrier Package (TCP) format, or mounted on a Mobile Module (MMO). The module held the processor, 512KB of L2 cache, a VRM to buffer the processor from higher voltage components, a clock, and the new 430TX PCI Northbridge chipset. The module was connected to the motherboard by a single array of 280 pins, just as on the Pentium II's SEC cartridge.

There were various reasons for putting the chip on a module. From an engineering point of view, it made it easier to combat the two main problems which arose in the area around the processor; namely heat and connections. The voltage regulator and the lower voltage of the chip helped dissipate the heat. A temperature sensor was located right by the processor, which triggered whatever heat dissipation method the manufacturer had built in. The 430TX chipset then bridged the gap between the processor and the other components, communicating with a second part of the chipset on the motherboard which controlled the memory bus and other controllers such as the graphics and audio chips.

Intel maintained that the MMO made life easier for the notebook OEMs, which could now devote more time to improving the other features of notebooks rather than having to spend too much R&D time and effort on making their systems compatible with each new processor. And, of course, as most processors required a new chipset to support their functionality, manufacturers were spared the dual problem of redesigning motherboards for the purpose and of holding obsolete stock when the new processors came in.

On the flipside, it neatly cut off the route for Intel's competitors by forcing notebook OEMs to go with Intel's proprietary slot. However, the much-vaunted idea that the module meant easy upgrading for the consumer was little more than wishful thinking. In practice, it was far more complicated than just opening up the back and slotting in a new SEC, as in a Pentium II desktop. Its size was also a downside. At 4in (101.6mm) L x 2.5in (63.5mm) W x 0.315in (8mm) H (0.39in or 10mm high at the connector), the module was too bulky to fit into the ultra-slim notebooks of the day.

January 1999 saw the family of mobile Pentium processors with MMX technology completed with the release of the 300MHz version.

Laying Out A Great Looking CD-ROM: 7 Tips To Increase Usability

Don t you just hate popping a CD into your drive and having to guess at what to do next? Yeah, me too!

As a software/multimedia developer your aim is to educate and/or entertain your users, so giving them a CD which takes them straight to the heart of your content will only enhance their experience. So, before mailing your master disc to your favourite CD duplication company, here are a few ideas to think about:

1. Does the CD autorun?

The vast majority of Windows users expect their discs to autorun, so why disappoint them? Make the CD autorun the way you want by popping a simple text file, called autorun.inf, into the root directory of your disc. There are loads of websites explaining how to do this, just Google "How to create an autorun CD".

2. Have you assigned an electronic volume label to the disc?

Many CD authors overlook this, so when users navigate their PCs using Explorer they can see that a CD is in the drive, but the text next to it says New or maybe something like 130982 not very descriptive! Set the volume label using your burning software, or try using the label command inside the autorun.inf file.

3. Do the CD and main executable file have their own icons?

Replace the default CD icon the one you see when viewing the disc in Explorer with something more appropriate, your logo or a small graphic for example. Grab a free icon from the Internet or use one of the available free icon editors to create your own and use the icon command inside the autorun.inf file to assign it to the CD. Also, you can assign the same icon to the main executable file when compiling, or if that s not possible, use a program like Resource Hacker to add it afterwards.

4. Is the root directory free of clutter?

People don t want to be confronted with a choice of files to click, so make the choice for them and only leave the most important one in the root directory (along with your autorun file of course!). Maybe give the file a name such as start or run to make it obvious, and move all the other files into sub-folders.

5. Do the sub-folders and files have real names?

By giving folders and files human-readable names it allows your users to navigate around the CD and locate documents and images outside of your software or presentation.

6. Have you removed all unnecessary files from the CD?

When creating your master disc be sure not to include unnecessary files, images or templates. As well as a clean file structure, it prevents you giving away source code and any half-completed, unused ideas!

7. Is the CD to be used on PC and Mac?

If the disc is to run on both platforms make it a true hybrid CD, so there are dedicated PC and Mac areas to the disc with any files common to both sides being shared. This way you can hide the PC files from the Mac and vice-versa, making for a cleaner disc.

Follow these tips and you ll end up with an easy to use and professional looking CD.

Speeding Up a Slow Computer

Whether you re a home user or you use your computer for business purposes, a slow running system can be quite annoying. It doesn t take long for a once fast computer to seemingly slow to a halt.

Older computers are expected to be a little slower, unless you ve done a lot of upgrading they just aren t equipped to keep up with todays standards. But, even a brand new computer can become slow after even a few months of use.

A computer can become slower due to hardware problems, but many times the problem occurs simply because there s to many processes running at the same time. Often when you install a program it will by default set itself to start as soon as you start your computer.

There are probably processes running in the background that you re not aware of and they re consuming your computers resources. Anytime you install any program carefully watch the selection screens, sometimes you will be offered the option of either automatically starting the program or manually starting it.

If the choice isn t offered then you will need to go into the preferences tab in the program itself and customize the options. Aside from your operating system the only programs that should run each time you start your computer are your anti-virus, firewall and anit-spyware programs that you have.

Another major cause of a slow computer is a crowded or fragmented hard drive. Your operating system needs a little "elbow room" to properly perform, at least 10% of your hard drive space should be left free for paging operations.

Even during normal use files become separated and stored in different places on your hard drive. But, moving, deleting files. installing or uninstalling programs leave fragments of files behind. Performing the defrag option on your computer will rejoin these files and help optimize the performance and speed of your hard drive.

Regularly clearing your cache files and cookies can provide faster internet browsing. The cache files consist of temporary files that are stored each time you visit a web site. These eventually take up much of the memory of your computer and will cause it to run slower.

Integrating a pop-up blocker into your browser will also speed up the amount of time it takes pages to load. Some sites are full of pop-up s that eat up CPU usage to load. There are several free pop-up blockers available and many browsers will offer plug-ins that will block pop-ups.

Most of the things that will slow your computer down actually occur over a gradual period of time and are sometimes not real noticeable. But, if your computer ran fine yesterday and is dragging today, the most likely cause is a virus, spyware or trojan.

Never run your computer without a anti-virus and firewall and make sure to do perform regular updates. The best way to keep your anti-virus updated is to set it to do automatic updates, that way you won t have to remember to do the updates! Having an outdated anti-virus program is almost as bad as not having one at all, any new threats since the last update will not be detected.

Just as your hard drive becomes covered with files that are no longer needed, your registry also contains left over files from things such as uninstalled programs that can decrease the speed of your computer.

Finding and using a registry cleaner will remove these file fragments and speed up your computer. However, the registry contains everything that windows needs to run and one deleted file can prevent your operating system from working at all!

Before you download and install any registry cleaner do some research, there are many places online that offer individual reviews of programs. After running the registry cleaner, always look through the list of files to be deleted.

Sometimes files are included that are necessary to the operating system or programs that you use on a regular basis. If you re unsure whether or not to delete a particular file, do a internet search and see what the file is for.

If you ve taken all the steps needed to increase your computers speed and it s still running slow, then the problem is probably with the hard ware. Either something is experiencing problems or just needs to be updated!

Writing In Information With Customised USB Pens

There are several ways to help others remember who you are or to put together something that is different from the rest of the office and technology items that they have. If you want to make sure that you are putting together a different set of items then you can combine your options with customised USB pens. These gadgets are designed to create all in one features that add into the memory for the office.

When you begin to look into customised USB pens it is important to start with knowing how the different pens

are designed. Typically, there will be a USB drive on one side of the pen. This may be attached at the back of the pen or will open in the middle of the pen. This allows you to save the information needed on the pen. When the pen is attached together, there is also the ability to write with the pen on a piece of paper. The result is the ability to get two items in one.

If you want to make the most out of this item then you can work towards customised USB pens. This provides you with more capabilities towards having a unique object in the office. Customised USB pens are a convenient item to give as an office gift or can be used if you are working on promoting your business. The result is the ability to use the pen as a way to create memories in more than one way.

Looking into customised USB pens starts with finding the right way to customise the object. With most of the pens you can begin with printing the name of something or putting a graphic on the outside. This can help you with promotional items or allows you to create a style that completely belongs to you. By adding in the right prints you can make sure that you have the most effective statement on the outside of the pens that will remain written on for others to remember specific concepts that apply your own ideals and philosophies.

For anyone who wants to write in memories, the best way to start is by combining in technology with personalised options. One of the best tools that can be used for this is through customised USB pens. This hybrid piece of equipment can help you to make the most out of writing, saving files and helping others to remember who you are. Knowing the basics of this is the beginning to creating the perfect image through the items that you have.

Service Contracts - Part II, Fax Machines

If you are shopping for a new fax machine you may need a service contract to go along with it. In this article you will learn the ins and the outs of service contracts, read on

Welcome to Part II of our three part series on service contracts. This article covers service contracts on high volume laser fax machines. Service contracts on high volume fax machines are much different than service contracts on a copy machines. The difference is that fax machines are not billed by cost per copy. If you read my previous article Service Contracts on Copiers," then you know that cost per copy means that you are billed each time you make a copy. Fax machine service contracts are billed differently.

Understanding what is covered and what is not covered is very important to find out before you purchase a service contract on your fax machine. Most fax machine service contracts are billed annually and the supplies are normally not covered. Many service contracts do not include toner, drums or heat rollers. Many service companies will sell you supplies at a discounted rate as long as you are continuing to keep your machine on contract. They also may add an additional charge to cover circuit boards.

You can also purchase a cleaning only contract." You can purchase two or three cleanings or service calls per year in advance at a discounted rate. This way you keep your machine clean and if you run into trouble and you need to place a service call you will save money.

I always recommend installing a high quality surge protector on all copiers, fax machines and laser printers. This will protect your machine from power surges that could destroy your machine. Some surge protector companies have a guarantee that covers your machine if their surge protector does protect your machine against a high voltage surge.

Service contracts are similar to an insurance policy. They may or may not save you money. Many companies do not purchase service contracts on fax machines because they don t cover everything as copier contracts do. They service their machine(s) on a per call basis. You will have to decide for yourself or your company if you will purchase a service contract for your fax machine.

How To Choose The Best PC Gaming Headset

A good PC gaming headset is almost a must if you want to have the best gaming experience. Most games nowadays are embedded with high definition audio effects. To really enjoy the game and be in the game, a good gaming headset is necessary.

So what constitutes a good PC gaming headset?

Comfort

A good computer gaming

headset must be able to provide comfort to the user. This is necessary since you will be wearing it for a long period of time. There is only one way to test whether a headset is comfortable or not, and that is to try it out before you make your purchase.

Most of the time, the comfort factor is dependent on the:

Padding - Is it thick and soft enough to protect your ear?

Ear cups - Is it big enough to contain your ear?

Headband - Is it freely adjustable to suit the size of your head?

Weight - Is it too heavy for your ear to carry?

Put it on for 15 minutes and you will know whether it is suitable for you or not.

Sound Quality

A good PC gaming headset must have the ability to produce great sound quality. While different people perceive sound differently, you can use these few guideline to distinguish a headset with good sound quality from a bad one.

Bass

A gaming headset with a powerful bass will show significant differences in first person shooting game such as Counterstrike. You will be able to hear clearly the bullets flying around you and distinct explosion in the background.

Surround Sound

Surround sound effect is necessary to create the realism in your gameplay. Those PC gaming headsets with 5.1 digital audio encoded will be useful to help you identify the enemy that is sneaking behind you or shooting at you

Noise Cancellation

Some gaming headset uses an external microphone to pick up external noise and invert them to cancel out any unwanted noise. This is extremely useful if you are always playing in a noisy environment, such as an Internet cafe.

Cable Length

The cable length will determine how far away you can stay behind the screen. A typical gaming headset should have a cable length of 2m. Anything shorter than this length will restrict your movement and cause inconvenience to you. If you are playing game console, such as Xbox or PS3, in your living room, you might consider getting a headset with longer cable or an extra extensible cable to connect to your headset.

Wireless Headset

If you always move around and do not wish to be bothered by the cable, you can choose the wireless gaming headset that makes use of Bluetooth or RF technology. A word of caution, wireless headsets might be more prone to noise interference and/or loss of signal during the transmission, which can lead to static, pops or annoying noise.

Microphone

Some of the PC gaming headsets are geared with a microphone to allow interaction during gameplay. This might be a useful feature that you want to include in your gaming headset.

Volume Control

This may seem a trivial feature, but it matter a lot when you are far away from your sound system. For a gaming headset with surround sound feature, it would be useful to have an inline volume control to control the individual speaker levels. You can customize the volume setting for each speaker to enhance your gaming experience.

Vibrator

Force feedback gaming headsets make use of vibration to try to recreate the physical sensation of bass frequencies. The headset can vibrate in sympathy with the low frequencies in the audio signal, so that listeners both hear and feel the bass.

These should sum up most of the features found in a good PC gaming headset.

In conclusion, choosing a good PC gaming headset can be a very personal thing. A headset might fit comfortably on others, but not on you. You will have to try out the headset before deciding whether it is suitable for you.

Apples Pages 08 is All Grown Up

Apples Pages 08 is All Grown Up

Previously known more for its page layout capabilities than for its word processing capabilities, Pages now enables users to switch seamlessly between writing and designing documents.

School District Uses Laptop Tracking to Simplify IT Asset Management

Mitigating Expensive Data Center Changes!

Incorporating the iPhone into the Enterprise

Financing IT in Tough Economic Times

iWork 08 is reasonably priced, at $79 (or free with the purchase of any new Mac computer). The suite requires Mac OS X version 10.4.10 or later.

Perusing Pages

CPU Technology - part 4

Cyrix MediaGXi

The merging of graphics, audio, memory control and the PCI interface onto the microprocessor itself, made Cyrix's revolutionary MediaGX architecture a natural for use with notebook PCs, delivering easy-to-use multimedia technology at an affordable price while optimising battery life with its low-power design. In late 1998 the MediaGXi processor was instrumental in enabling notebooks to break the sub-$1,000 price point. The processor's suitability for deployment on a small, sparsely populated motherboard also made it an attractive option for use in the sub-A4 "mini-notebook" format.

Virtual System Architecture (VSA) was Cyrix's software technology which replaced hardware functionality traditionally implemented in add-on expansion cards. VSA and the integrated features were complemented by three exclusive processor technologies that managed the multimedia and system functions of the MediaGX processor - XpressRAM, XpressGRAPHICS, and XpressAUDIO:

XpressGRAPHICS technology eliminated the need for a graphics card. In a traditional PC, graphics are processed away from the main CPU through the slower PCI bus. However, with the graphics controller and accelerator moved onto the MediaGX processor, graphics processing took place at the full megahertz speed of the CPU. XpressGRAPHICS also implemented an innovative graphics compression scheme with high-speed buffering, allowing flexibility in memory configuration without the need to add expensive video memory.
XpressRAM technology enabled the MediaGX processor to avoid the delays of data moving between the external cache and main memory. By placing the memory controller onto the chip, data lookups moved directly to SDRAM and back to the CPU, eliminating the need for external cache
XpressAUDIO technology took over the operations of a separate sound card. Compatible with industry-standard sound cards, it generated all sound directly from the processor set, thereby avoiding the performance and compatibility conflicts that often occurred between audio and other components.

The MediaGX architecture represented true system-design innovation and intelligent integration. However, the lack of a Level 2 cache had an adverse effect on overall system performance, reinforcing the impression that the processor was best suited to low-end, low-cost systems.

Mobile Celeron

Co-incident with the launch of Dixon, Intel also introduced its first Mobile Celeron CPUs, at clock speeds of 266MHz and 300MHz. Technically, these CPUs were distinguished from the Dixon range only by the fact that they had 128KB of on-die Level 2 cache, rather than 256KB. However, they were priced extremely competitively, confirming Intel's determination to gain market share at the budget end of the market.

By the autumn of 1999 the Mobile Celeron range had been extended to provide versions at clock speeds up to 466MHz, all based on Intel's advanced P6 microarchitecture and having an integrated 128KB L2 cache for increased performance, and the 466MHz and 433MHz versions available in all of Ball Grid Array (BGA), Micro Pin Grid Array (PGA) packaging - consisting of a processor and a tiny socket - and Mobile Module (MMO) packaging.

In 2001 the 0.13-micron Pentium III Tualatin chip became key to Intel's mobile CPU strategy. By that time notebooks were available in a variety of sizes, ranging from full-featured models with 15in screens to ultraportables as thin as 20mm and weighing as little as between 2 and 3 pounds. Different manufacturers refer to the smaller form factors variously as "slimline", "thin and light", "mini-notebooks" and "sub-notebooks".

The situation had become equally as confusing with respect to versions of mobile chips. For example, Intel manufactures a mobile Pentium III and a corresponding Celeron chip for each notebook category. Whilst the latter cost less, they were based on the same technology as their siblings differing only in cache sizes, core voltages and processor packaging.

By the spring of 2002 Mobile Celeron CPUs were available for core voltages between 1.15V and 1.7V in a variety of speed grades up to 1.2GHz for standard voltage versions and 677MHz and 670MHz for low voltage and ultra low voltage versions respectively.

Reducing Costs - WAN Acceleration

WAN Acceleration

According to Gartner, WAN optimization is about improving the performance of business applications over WAN connections. Most networks carry a variety of types of traffic, of differing characteristics and importance. Many organizations are striving to manage this traffic to optimize the response times of critical applications

and reduce costs, given that bandwidth continues to represent a significant proportion of operating expenditure for wide-area data networks.

The primary function of a Web Optimization Controller (WOC) is to improve the response times of business-critical applications over WAN links, but they can also help to maximize return on the investment in WAN bandwidth, and sometimes avoid the need for costly bandwidth upgrades. To achieve these objectives, WOCs use a combination of techniques, including:

- Ensuring fair access for mission-critical applications during periods of congestion by prioritizing business critical traffic, through QoS policing and traffic shaping, for example

- Minimizing the effects of network latency using methods like protocol- and application-specific optimization

- Reducing the bandwidth required to transfer WAN traffic by compressing it, for example.

Click here to read more from Gartner about the WAN optimization market.

The WOC market is maturing rapidly, but it is still dynamic with a high level of vendor innovation.This has led to different vendors offering different combinations of features. In order to ensure that the most effective solution is put in place, providing the best overall return on investment, a detailed analysis should first be undertaken. This will establish:

- The real bandwidth you are achieving

- The real usage of that bandwidth

- Applications and services running on your network and the protocols they use

Also conduct a detailed analysis of your network traffic to identify specific problems, for example, excessive latency, bandwidth over subscription or lack of prioritization for certain types of traffic.