October '98 Video Accelerator Comparisonby Anand Lal Shimpi on October 12, 1998 8:42 PM EST
- Posted in
What to look for in a Graphics Accelerator
Acceleration Strengths - What sort of acceleration do you primarily need? While a card may offer excellent 3D acceleration there are some out there that need more than the ability to run Quake 2 at unbelievable speeds.
API Support - Glide, Direct3D, and OpenGL. Those are the three major Application Programming Interfaces (API's) you'll see present in the 3D world, while only 3Dfx cards support the least used Glide API Direct3D and OpenGL support are provided for with virtually any card/chipset. If OpenGL is something you're looking forward to having outstanding performance under, then make sure that the card you're after has full OpenGL support now with an OpenGL Installable Client Driver (ICD) available for download.
Drivers & 3DNow! - Make sure that the manufacturer of your next-generation graphics accelerator won't leave you in the dark when the time to upgrade your drivers comes around. Keep track of all driver updates made to manufacturer websites and be sure to keep communication lines open between yourself and the manufacturer (that's what email is for). For you K6-2 users, you may want to lean towards a graphics accelerator chipset that has either current or planned support for AMD's 3DNow! instructions in their drivers. Among others, 3Dfx, 3DLabs, Matrox and nVidia have either announced or currently have drivers out that support the AMD 3DNow! instructions.
Interface & Card Length - Two very important factors in purchasing a graphics accelerator, the Bus Interface and the physical length of the card. For PCI cards, you must make sure that you have at least one open PCI slot that can accommodate the physical length of the card. Voodoo2 accelerators, for example, require full-length PCI slots due to their incredible length. Unfortunately those are luxuries denied to most AT-Super7 motherboard owners, in which case an AGP accelerator becomes more attractive especially since PCI slots are quickly increasing in scarcity among upgraders.
Refresh Rates & Integrated RAMDAC - If you have a 14" monitor and don't have any plans on upgrading your monitor in the near future then you should probably skip this section. For those of you that have either taken advantage of or are planning to take advantage of the rock bottom prices on 17" monitors or for those of you that simply have the budget for a 21" monitor, then you will want to pay close attention to the supported Refresh Rates and Integrated RAMDAC of any graphics accelerator you purchase. The rule of thumb here, the higher the better, it is as simple as that. Remember that when outputting video you must take the digital data stored in your video memory or RAM and send it down your VGA cable to your monitor. However monitors, in spite of what you may think, do not receive information in digital bits since they are analog devices. In order to convert the digital signal from the RAM to an analog signal the monitor can use a RAMDAC (Random Access Memory Digital-Analog Converter) is present on the video card itself. The faster a RAMDAC the better the 2D image quality you see on your monitor will be. Expect most RAMDAC's to fall in the 200MHz - 250MHz with 230MHz as the sweet spot for most users.
Rendering Capabilities - Need to be able to render in a window rather than a full screen application? Look into the specifications of the graphics chipset you're considering and ask yourself: does it allow for a 32-bit internal accuracy for rendering calculations? Does it support 32-bpp rendering? Is color expansion optional in the future with this chipset, and what sort of performance hit will result if such an expansion is initiated?
Resolutions & Video Memory - If you have an ideal resolution in mind, one you would like to run all of your games at as well as another you wish to keep your windows desktop at you need to make sure that the video card you're purchasing has enough memory (or a large enough frame buffer in the case of 3D accelerators) to accommodate for the resolution. The once sought after 640 x 480 gaming resolution is now a thing of the past, you should accept no 3D accelerator that doesn't allow for 800 x 600 support, and provided that the performance is decent, support for higher 3D resolutions such as 1024 x 768 and 1280 x 1024 can be desired as well. Just remember that your monitor must also be able to handle the resolutions you're aiming for, 800 x 600 and 1024 x 768 are pretty much supported on all monitors (even 14" monitors have 1024 x 768 support) however once you break 1024 x 768 you may want to start looking for a 17" or larger screen.
Texture Units - A key to continued levels of high performance in future gaming titles will lie in the ability of a card to process textures in an efficient and effective manner. Currently, the most popular way of achieving this effective and efficient is by offering two separate texture units, each of which capable of processing a single texture - paving the way for high performance under multi-textured gaming situations where a single texture is overlapped by the presence of another one.
TV-Output - The world of TV-Output has matured tremendously since the days when ATI's 3DXpression+ dominated the boards with its "crisp and clear" TV-Output. Companies have already begun pushing the limits of TV-Output to previously unheard of degrees, Matrox's Mystique G200 supports a TV-Out resolution of up to 1024 x 768. If you have a large enough TV in the area where your computer will reside, then you may want to give TV-Output another look, for the first time.
Finally, there's price, and without further ado let's get to the roundup...