The Voodoo3 2000 PCI would work wonders in just about anything. I personally recommend at least a P166MMX and 32MB memory. When I added it to my K6-2 350 with 32mb PC-66 and 2-8mb SIMMs I ran Q2 8-10 times faster with OUTSTANDING image quality.
Otherwise a Voodoo2 1000 might work good. They can't pull anything close to a V3 at higher resolutions, but they smoke at lower resolutions, giving older systems a BIG performance kick. They might be a better card for anything below 300Mhz.
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