With current developments in rock-bottom video card pricing, improvements in 3D display technology, and massive amounts of high-speed memory available on new video cards (up to 256MB!), it makes little sense today to add most upgrades to an existing video card. The component-level upgrades that can be added generally include:

• TV tuners, permitting you to watch cable or broadcast TV on your monitor

• Video capture devices, allowing you to capture still or moving video to a file

If you need better 3D performance, more memory, or support for DVI digital displays, you need to replace your video card.

TV Tuner and Video Capture Upgrades

Most video cards don't have TV tuner and video capture upgrade features built in. New cards with these features tend to be either in the middle to high range of their manufacturers' price structures or less expensive but of poor quality. These features are exciting if you are already into video editing, want to add video to your Web site, or are trying to create CD-R/CD-RW archives of your home video.

If you have an up-to-date video card with acceptable 2D and 3D performance and at least 16MB of video RAM, compare the price of the add-ons to the price of a new card with these features. You'll probably find the add-ons to be less expensive. If your card has 8MB of video RAM or less, I'd recommend replacing it with a new card with these features.

Look at sample video captures before making your decision because all video capture solutions require image compression with at least some loss of quality. If you have a digital camcorder with IEEE-1394 (also called FireWire or i.Link) ports, you should purchase an IEEE-1394 interface board instead to use high-quality pure digital video that needs no conversion.

Note that ATI's All-in-Wonder RADEON 8500 DV includes an IEEE-1394 port as well as TV-in capability, allowing you to use a single card for high-performance business and gaming graphics as well as digital and analog video capture. The USB port found on recent systems can be used to connect TV tuner and video-capture options compatible with any manufacturer's video card, such as the ATI TV-Wonder USB Edition or Hauppauge's WinTV-USB.

Warranty and Support

Because a video card can go through several driver changes during its effective lifetime (about three years or two operating-system revisions), buying a video card from a major manufacturer usually assures you of better support during the card's lifetime.

If you buy a card that uses widely available chipsets (such as NVIDIA's), you might be able to try a different vendor's version of drivers or use the chipset vendor's "generic" drivers if you don't get satisfactory support from your card vendor. Keep in mind that using generic drivers (chipset level) or a different brand of drivers can cause problems if your original card's design was tweaked from the chipset maker's reference design.

Look at the vendor's technical support forums or third-party discussions on newsgroups, computer information Web sites such as ZDNet, or magazine Web sites to get a feel for the stability, reliability, and usefulness of a vendor's support and driver services.

These sources generally also provide alternatives in case of difficulties with a specific brand or chipset. If you use Windows Me, Windows 2000, or Windows XP, make sure you use WHQL-certified drivers for best results. These drivers have been passed by Microsoft's Windows Hardware Quality Labs and might be available through Windows Update or from the vendor's own Web site.

Comparing Video Cards with the Same Chipset

Many manufacturers create a line of video cards with the same chipset to sell at different pricing points. Why not save some dollars and get the cheapest model? Why not say "price is no object" and get the most expensive one? When you're faced with various cards in the "chipsetX" family, look for differences such as:

• RAMDAC speed - Most current 3D accelerator cards use a 300MHz or faster RAMDAC, which provides flicker-free resolutions beyond 1024x768. However, less-expensive cards in older designs often used a slower RAMDAC, which reduces maximum and flicker-free resolutions. If you use a 17'' or larger monitor, this could be an eye-straining problem.

• Amount of RAM - Although AGP video cards can use AGP memory (a section of main memory borrowed for texturing), performing as much work as possible on the card's own memory is still faster. PCI cards must perform all functions within their own memory.

Less expensive cards in a chipset family often have lower amounts of memory onboard, and most current-model cards aren't expandable. Buy a card with enough memory for your games or applications—today and tomorrow; at least 32MB or more for business and 64MB or more for gaming, 3D graphics, and video-related work.

• Memory type - Virtually all video cards on the market today use SDRAM or its faster variants (SGRAM, DDR SDRAM, or DDR-II SDRAM). Any of these provides you with high performance in business applications, although DDR or DDR-II SDRAM is preferable when running high-resolution, high-quality 3D games faster.

• Core clock speed - Many suppliers adjust the recommended speed of graphics controllers in an effort to provide users with maximum performance. Sometimes the supplier can choose to exceed the rated specification of the graphics chip. Be cautious: Current controller chips are large and can overheat.

An overclocked device in an open system with great airflow might work, or it might fail in a period of months from overstress of the circuitry. If you have questions about the rated speed of a controller, check the chip supplier's Web site. Many reputable companies do use overclocked parts, but the best vendors supply large heatsinks or powered fans to avoid overheating. Some vendors even provide on-card temperature monitoring.

• RAM Speed (ns rating) - Just as faster system RAM improves overall computer performance, faster video card RAM improves video card performance. Some high-performance 3D video cards now use DDR SDRAM memory chips with a 2.8ns access time.

• TV-out - Once a rare feature, many mid-range and most high-end video cards now feature TV-out, enabling you to display DVD movies or video games on a big-screen TV. Some of the latest models have hardware-based MPEG-2 compression for higher video quality in less disk space. Some of the latest video cards are now using a VIVO-out port to support either RCA or S-video inputs on VCRs and TVs.