Voodoo3™ Reviewers Guide
August 1999
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SECTION 5: Testing Recommendations
Testing the Voodoo3 Board
When testing Voodoo3 2000 or 3000, we recommend you work in the highest resolution
possible. The key strengths of Voodoo3 are phenomenal graphics memory bandwidth and high
pixel fill rates. In other words, you can still achieve high frame rates at high resolutions. As an
example, when working with a Voodoo3 3000 card running on a 400MHz CPU or better, try
testing Quake II at 1024 x 768 resolution: You should expect to see well over 30 frames per
second! Leading triangle setup and pixel fill rates mean Voodoo3 will rarely be the “bottleneck”
to gaming performance in a PC system: Indeed, the faster your PC’s CPU, the more you will be
able to witness the extent of Voodoo3’s graphics power.
Voodoo3 incorporates many features to optimize the image quality of 3D content. For
example, to see the impact of Voodoo3’s per-pixel trilinear mapmaking and accurate LOD
calculations - simply look at a polygon in perspective, e.g. a floor or wall in Quake or Wiz and
move slowly forward/backward. You won’t see any mipmap bands (caused by bilinear or poor
trilinear filtering). Neither will you find aliening or sparkling (caused by inaccurate LOD), or
mipmap "popping," which is an abrupt change in sharpness or blur (per-polygon mapmaking will
cause this).
Cures to common benchmarking and image quality issues
•
Be sure to use the New MiniGL drivers that are on the CD.
•
When testing Quake II, go to the video options and turn off 8-bit textures. This
removes banding when viewing the sky by allowing the game to use the higher quality
16-bit textures.
•
Prior to testing frame rates, ensure that vsync is disabled. Before you do any frame
rate testing make sure that vsync is disabled. You can do this by downloading
PowerStrip from http://www.entechtaiwan.com/ps.htm or by adding the following to
your autoexec for opengl/glide:
SET FX_GLIDE_SWAPINTERVAL=0
•
For D3D, you will need to edit the registry and enter a new string value under
[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\Display\xxxx\D3D]
(xxxx will be 0000, 0001 or higher)
SSTH3_SWAPINTERVAL 0
•
When grabbing screenshots, keep in mind
3dfx has a unique way of converting data
in the frame buffer before we send it to the screen to be displayed. As a result, we
store “unfiltered” data in the frame buffer - and the filtering is performed at scan-out on
the way to display. This improves the quality of the picture displayed on the monitor,
but doesn’t actually change the data in the frame buffer. Typically when you are
doing a frame grab, you are just grabbing data directly from the frame buffer, which is
“unfiltered” so the quality of raw images grabbed from the frame buffer is actually
lower than what is actually displayed. HyperSnap, a frame grabbing utility, actually
implements our filtering technique on their frame grabs, producing a more accurate
