The Specs Explained
You can delve as deeply as you like into graphics board specs, from RAMDAC to clock speeds, until your 3D-rendered head spins. But the specs to stay focused on involve a graphics board's interface, chip set, and memory, as well as any ports that you may need.
Most PCs now have the faster PCI Express rather than the older AGP slots, but choose whichever interface your PC supports.
Important: Chip Set
After the interface, deciding on a chip set is your next major decision. Go to the links for our Top Graphics Cards charts to get an idea of how different chip sets perform.
Important: Video Memory (Installed RAM)
With more video memory, your graphics board can hold more image data, leading to faster rendering of textures and 3D graphics. These days, many of the value boards appearing on our chart have at least 256MB of RAM, an amount that is standard on mainstream boards. Power boards generally have 512MB of RAM. At least one has 768MB, and one dual-chip card has 1024MB of RAM.
Important: Graphics Processor Clock Speed
While the clock speed of the graphics processor is a good overall indicator of how fast it will render 3D graphics, the high cost associated with top-of-the-line processors is no longer an absolute indicator of performance. The same holds true on the low end.
Important: Monitor Ports
All new graphics cards have two display connectors for hooking up two monitors; and most have at least one DVI port. Still, for the maximum image quality on two LCD screens, you want to make sure you have two native DVI ports, though in a pinch a DVI port can connect to a VGA display if you have a DVI-to-VGA adapter (often included with the board itself).
Important: Output Ports
If you want to edit video, use your PC as a digital video recorder, or even just connect it to your big-screen TV to play games or watch high-definition video, you'll want a graphics board with output ports that match your video devices. Most value and mainstream boards have at least S-Video and composite ports. And most mainstream and power boards have component video, and some have HDCP support for viewing Blu-ray Disc and HD DVD content.
Important: Slots Occupied
Before you buy a huge graphics card, make sure you have the room inside your PC to fit it. Some cards take up the space of two PCI Express slots. Go to the links for our Top Graphics Cards charts to find this spec on boards that we review.
Somewhat Important: RAM Type and Speed
Graphics boards come with different flavors of memory--DDR2 and DDR3 being the two most common ones right now. The newest cards have an even faster DDR4 memory. While in theory DDR4 memory is faster than DDR3 memory, other factors on a board also affect performance. The same logic goes for RAM speed.
Somewhat Important: Input Ports
Unless you want to record video or audio from a TV or camcorder, you likely won't need video and audio inputs. Some graphics boards also come with a TV tuner, which is great for watching TV in a dorm room, for example. But keep in mind that a TV tuner adds to the cost of the board in all categories.
Somewhat Important: SLI/CrossFire Support
Unless you really plan on using two or more graphics boards in tandem, you don't need a product that supports dual-card technologies.