Recently 3d Labs supplied me with an 8 meg version of the Permedia 2 based accelerator on a View Top board. Unlike the memory on 3dfx boards Permedia 2's memory can be used indifferently for the color buffers, the Z-buffer, or for texture storage. So, for example, if you are running a game at 640 x 480 x 16 bpp, double-buffered, full-screen, with a 16-bit Z-buffer, then you have about 6MB of memory left, which you can use for texture storage.
To check out the board I swapped out the Velocity 128-3d from my AMD 233 and installed the P2 board. Using a recent beta driver I had no problem at all with installation. I then booted up F22: ADF. There was little perceptable difference in speed under Direct3d, and also no perceptible difference in quality.
I then booted up my Gold copy of JSF. JSF allows any resolution you can run, so I first tried the resolution I had been running previously for a comparison. At 800x600 x 16 bits speed was down slightly, I would guess about 15%. That was as high as I could run with the 4 meg limit of the Riva chipset on the V128. However, the Permedia chipset can address more memory, and I now had the option of running up to 1280 x 1024!
I tried 1024x768 first. At medium detail the sim was still playable. I increased detail to maximum and frame rate dropped to about 8 fps. I went back to medium detail and went to 1280x1024. At this resolution JSF is a very pretty slide show! But on a PII system at 300+ MHz you could run at maximum detail at 1024x768 with this board and really enjoy the view! I then ran the Tomb Raider 2 demo at 800 x 600 x 32 bpp. WOW. Lara didn't know she could look this good!
Lighting and fog effects look just fine with this board. I ran Longbow 2 in a night mission and a day mission with detail cranked up to see what it would look like. I couldn't tell any difference from the V128, but I was surprised that in Longbow 2 with detail at max my frame rate seemed the same on the ViewTop.
There are several chips out there that do triangle/geometry setup in hardware, even in Direct3D. For example, PERMEDIA 2 does full triangle setup in hardware in Direct3D, and so do the Rendition chips. However, the current version of Voodoo does not do full triangle setup in hardware, even in Glide. According to Gary Tarolli himself, Voodoo does about 2/3 of the triangle setup.
What difference does this make? With new games increasing the number of triangles because of increasingly complex object modelling, these Permedia based boards may suddenly look as good or better than even Riva based boards. It will be interesting to see how Su27 2 runs on a Permedia board, for example, since this new engine is triangle intensive.
In the meantime, if you want the ability to run at even higher resolutions than the Velocity 128, this might be a good solution. If you are running in a PII system, you could be playing JSF at higher resolution than your friends, not a bad option!
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Last Updated December 5th, 1997