Video Cards Simplified

Cut through all the geek speak to identify what you really need to know.

Basic Concepts

The graphics/video card of a computer converts the electronic signals that the computer generates or transfers to it from external input into visual images. The level of clarity, definition and detail of the images depends on the power of the video card being used. The frame rate or the number of images or frames per second (fps) affect the quality of a moving or changing image and determine whether the motion will look jerky or be missing detail or will appear realistic.

In simplified terms, the video card needs intelligence provided either by the main computer of the system (i.e. the CPU or Central Processing Unit) or a special GPU – Graphics Processing Unit in the video hardware. It also needs memory to hold the information it is processing. It can share the computer’s main memory or provide some if its own memory and only use a fraction of the main memory or it may have its own independent memory. The more specialized the card is by having dedicated hardware the more powerful it will be and the more expensive it will be.

Selecting the right card for you

Dell Computers defines 3 levels according to this breakdown;

1. Low end – video uses computer CPU and memory

2. Mid Range – video card provides GPU and generally uses its own memory but may share some computer memory

3. High end – GPU and memory all provided by video card.

(See Dell Video Card Link )

The way you use your computer will determine what type of video solution you require

1. Basic user – word processing, internet browsing, email and DVD movies

The basic level card will suffice for this. It should have at least 128MB. 2 representative cards are the Nvidia 7300GT and ATI 1300XT.

2. Vista Aero User or light gaming, rich media, and general entertainment

Microsoft’s new operating system uses dramatic video effects to aid and enhance the user’s experience in working with their computer. Details are here;

http://www.microsoft.com/windows/products/windowsvista/seeit/default.mspx .

This capability requires mid level graphics power and a card with at least 256 MB of its own internal memory should be purchased. A sample card would be ATI HD2600XT.

3. Edit and view photographs in brilliant color

A mid level card should be used for this. One example is the NVidia 8600GT, All cards from this level and up should have at least 256 MB.

4. Playback HD quality content

The card should have HDMI outputs to attach to external displays. 2 possibilities are Nvidia 8600gt or ATI HD2600XT.

5. 3D accelerated gamesin high definition player, CAD (Computer Aided Design), video editing or high level graphic design

3D gaming makes the greatest demands on the computer’s video systems and the sky is the limit here. In general, the highest level card that your system will accept will provide the most satisfying experience.

The choice of video card will generally be made when you purchase a new system. Upgrading to a higher level would require having a new card installed. The ability of your system to accept a new card will depend on the age of your main computer hardware board known as the motherboard. The newer video cards require special types of connecters on the motherboard which will not be available on the older motherboards. This issue will be discussed in more detail in another article.

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3/22/2009