Thanks Swaaye. I've tried every driver I've been able to found in the web, the one that works best is 175.16 (2008).
I've tried switching off or setting to'performance' everything in the Nvidia panel, no change 😢 .
The only thing that works is setting 'AGP aperture size' to the minimum available (4) in BIOS. This speeds up things to a degree, but the game is still unbearably slow, almost frozing sometimes 😒 .
If the marine I control is say alone inside a closed room, things are up to speed, decent FPS. But as soon as bots approach, the game slows down to a crawl, and whenever there are explosions and bits of bugs and acid flying around, it almost frozes. So it could be that the CPU is being overloaded somehow with the 6200 and bottlenecking.
I'm expecting a Tualatin 1400-S in a couple of days, if I can make it work with this mobo maybe things will improve. Otherwise I'll have to discard the 6200 and search for another video card.
I know about AvP1 Classic, but that's why I'm building a PIII retrocomp, to play the originals 😉 .