Ugh, you might be SOL, 3Dfx died long before XP was released and its major product lines (V3, V4/5) have been kept alive on life support only through the generous contributions of enthusiast programmers out there.
Your best bet might be to check out
Voodoofiles or guru3D, as they're a few of the sites that continue to provide 3Dfx drivers on a regular basis. The only other thing I would try is the reference drivers for the capture chip on your tuner card. Not sure what it is though.
Chiz