The Video output system  in a computer governs the quality and performance of the images and moving graphics that are displayed on your monitor. In general if the computer is being used for business programs and internet operations only, the performance requirements for video control are simple and can be carried out by an 'on-board' chip integrated into the main board of the computer.
$ 39.00
Video card upgrades should not be attempted without technical knowledge and experience. Older control systems and drivers should be removed and disabled in the correct order prior to installing the new card.  Also, the video drivers shipped with the cards should never be used as better / updated drivers are always available via download from the internet. ( broadband only ~ video drivers are quite large )  
On-board Video controller systems are a part of the main board and acquire their RAM needs from the main System RAM. This is called 'Shared RAM' and is the reason why a computer with 256MB RAM may show only 192MB available as 64MB is being taken by the on board video chip. ( these figures vary depending on adjustments via the main board BIOS if available )
    High performance 3D Computer Games, Digital video editing, DVD production and even programs like Google Earth require better Video Performance than the on-board video system can deliver.  This is because the Game or program in question is attempting to do complex 3 dimensional and lighting calculations as it displays the images onto the monitor in real time. 
Dedicated Video Cards
    A dedicated video display card greatly helps to relieve the burden of 3D video calculations from the main board CPU and RAM by not only having it's own memory to deal with managing the changing graphics but it's own built in computer to do the complex math involved with creating moving detailed images with various textures and lighting etc. This is called a GPU ( Graphic Processor Unit )  
Dedicated video display cards differ in price and suitability for the following reasons:

• The type of main board they can be installed into
• The amount and speed of memory they have built in
• The speed of it's Graphic Processing Unit  ( and model )
• The type of cooling system it uses
• The manufacturer of the actual card and GPU installed

With the right advise, your computer may be upgraded with a dedicated video card to suit your needs. Or your initial purchase of a new computer can be made easier with better understanding of what video display system it has included in the price.

Before you choose a video card to upgrade your current computer or wish to ensure your new computer will come with a certain type of card, you will have to identify what type of 'Main Board' slots are available in the computer. Most computers will have at least one of these following  'slots or ports' available  
Which one suits your computer and your needs ?
Some Video Card examples:
GeForce 32MB TNT AGP
A simple low cost solution for a minor performance increase and to release shared video memory back to the main board. Minimum for Google Earth etc.
Used mostly for when an 'onboard' video system on the main board fails or steals too much memory.
GeForce 64MB MX440 AGP
$ 59.00
Same as the above card but a little quicker as it has double the RAM. Some older games may work better than the on-board video system was coping with but this card is useless for modern games. 
ATI Radeon 9250 128MB AGP
$ 79.00
Better again, and the display screen is starting to show quicker response to opening windows and folders etc. We can now think about attempting to change the screen resolution of our monitor to 1024x768 without noticeable lag. 
PCI      Peripheral Component Interconnect
This is an older style of video connection port and therefore Video cards to suit this type are very hard to find and will cost more than the newer style AGP and PCIE. A PCI based video card will never be able to support the latest 3D games but will improve many other programs like Google Earth or any Direct X requirements in software.

AGP       Accelerated Graphics Port
A popular style of video connection that although is still found in some new computers has been replaced recently by the latest type, the PCIExpress. If you have an AGP slot available you can upgrade to a wide range of video cards still being made to suit this type of interface.

PCIE       Peripheral Component Interconnect Express
The latest technology video port and if you are lucky enough to have one, there is an abundance of options to choose from. Also, this is the type of port you will want to find on your new computer. If the computer you are considering purchasing doesn't have a PCIExpress video port, dont buy it! ( unless you never intend to upgrade the video system ) A good punt if you are unsure about your needs for a dedicated video card, is to purchase a computer with an 'on-board' video system but with a PCIExpress port available for future expansion if you ever need it. 
    The following video cards are from my current range of stock offering a broad solution for the differing needs I come across during service calls and building new computers. There are hundreds of variations and if you are hunting down a particular type and model, please email me and i will endeavour to track it down for you.    
ATI 9250 128MB PCI
PCI Cards
As explained above,  PCI video cards are very hard to find now and this model is my only available option. It will help improve performance with all general display tasks including older games, but is useless for modern 3D games
$ 95.00
AGP Cards
GeForce FX5500 256MB AGP
Okay, now we are entering the 'performance' level of video cards that really start to make a serious difference with things like 3D games. Although still considered 'entry level'  3D games like the Sims2 etc will now operate at 1024x768 and be easier to play with a video card like this. Notice now the mention of GPU speed and Memory Speed. The higher these numbers, the faster the card can go. 
270Mhz CORE / 400Mhz Clock
$ 119.00
GeForce 6200A 256MB AGP
350Mhz CORE / 500Mhz Clock
Simply going faster now and this card gives a little more grunt to all round performance of mid range computer games and greatly helps with any other display related computer operations such as DVD video editing etc. 
$ 129.00
GeForce 7600GS 256MB AGP
400Mhz CORE / 667Mhz Clock
$ 229.00
A nice decently performing gaming card but by no means is the top of the line. Serious video gaming cards can cost upwards of $500 and require special cooling systems and power supplies to support them. This card is a respectable all rounder.  
PCIE Cards
GeForce 7100GS 256MB PCIExpress
350Mhz CORE / 550Mhz Clock
A nice start to upgrade your PCIExpress mainboard with a decent video card. Great value for money.  
$ 129.00
GeForce 7600GS 256MB PCIExpress
$ 195.00
400Mhz CORE / 800Mhz Clock
Your games are going to love this.  
GeForce 7600GT 256MB PCIExpress
575Mhz CORE / 1400Mhz Clock
... and if you want to check the edge of the serious stuff, this card will tease you without being too ridiculous in cost. PCIE cards beyond this level do go faster still, but you really start paying though the roof ( and there will always be a faster card released 3 weeks after you think you have the best! )   
$ 269.00
Important note:

A computer system's total performance is the sum of
ALL of it's parts. The video card plays a major role but will never reach it's optimum output ( and may not even work at all ) without support from a decent class of CPU,  hard disk drive, system RAM, powersupply, main board and cooling systems.  Also, the condition of the operating system is critical for a computer to handle high performance video tasks. A computer that crashes constantly when playing 3D games or when trying to edit a DVD movie production is a common symptom of poor quality or inadequate supportive hardware and / or a corrupted unbalanced operating system. In many cases I have suggested to some customers that they would be better off purchasing a games console such as an X-Box etc rather than attempting a computer video card upgrade simply to play better games, as high performance computer gaming systems require serious dedication and cost a lot more to maintain.  Proffesional advice and inspection of your computer and your requirements are available by booking a free on-site assessment by phone or email.