Factors Affecting Video Card Performance
To a newbie shopping for a video card, the long list of specifications and features on the card's packaging may seem like a foreign language. But hidden somewhere in all that geekspeak are important facts that can help you estimate how well the card will work for you.
The most important factors affecting video card performance include:
Type of Interface
PCI-Express. The PCI-E bus is the current standard, replacing the AGP bus as the interface of choice for high-end video cards due to its phenomenal data speed.
AGP (Accelerated Graphics Port). AGP is a dedicated, high-bandwidth interface that is custom-tailored to video cards. AGP speeds of up to 8X are still available. The card's speed should match the speed of the motherboard's AGP interface.
PCI. PCI video cards are still available, but are used mainly as replacements or upgrades for pre-AGP motherboards.
Amount and Type of Video RAM
All video cards have at least some RAM on the card. The amount and speed of the onboard RAM has a major effect on the card's performance.
For typing documents in Word, for example, you don't need a high-end video card with tons of RAM. Pretty much any video card that's supported by your operating system will do in that case.
But for image manipulation, video editing, watching DVD movies, gaming, watching HDTV, or running CAD/CAM applications, more and faster RAM is needed. For these uses, you should consider an AGP or PCI-E card with at least 512 MB of fast RAM (like DDR-SDRAM). For high-end gaming or video editing, 2048 MB would be even better.
Similarly, if you're building a computer that's going to be used for text-only display, such as a Linux server without any graphical abilities, then you really don't need much in the way of video. The only thing that really matters in that case is that the video card or onboard video processor is compatible with your operating system. So don't spend a lot of money on a video card that has capabilities that you'll never use.
3-D/Open GL Support
All but the very lowest-end video cards come with 3D and Open GL support. Open GL is the industry standard for high-performance video, and is supported on Windows, Mac, and Unix machines, as well as on many industrial and other specialized devices.
Most high-end and many mid-range video cards now come with their own onboard cooling fans. This little feature can make a big difference when using the computer for video, gaming, or other graphics-intensive applications.
Aftermarket coolers are also available quite inexpensively for many video cards that don't come with them. (They're usually the same fans that are used as motherboard chipset coolers.) But installation of a fan on a video card can be a little tricky, so be careful.