Yes, I've been able to run quake3 on my dual processor NT4 system with a Diamond Monster Fusion banshee card. It's relativly simple, after doing a standard install just download the file 3dfxOGL.dll (I belive it's in the 3dfxgamers.com NT4 refrence driver pack for the banshee, if it's not there I can send it to you), rename it to 3dfxvgl.dll and put it in your quake3 base directory. When it asks you if you want to run windowed or full screen hit 'OK' and you're in the game. If some of the menu's and buttons are distorted (dosent happen all the time), then hit F11 to deal with the problem.
I get 80+ fps at 1024x768 with my dual 333's
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