I've got a AGP Voodoo 5 5500 that refuses to function under any drivers aside from Microsofts generic sets.

*Windows 98 - it boots up and says it can't set any video modes aside from 16 color 640x480 due to hardware problems.
*Ubuntu - the edges of windows would "wiggle". It was like a side winder going up and around the edges of window. This is without any 3dfx support, just vanilla Ubuntu.
*Windows XP - works fine, wouldn't know that you were using the default video driver at all. Install the 3dfx driver or a 3rd party model and it would boot to a black screen. Rolling back the driver fixes it but of course its rolled back to the XP generic.

XP also reports that it's only got 1 VSA-100 chip and 32mb of ram. I'm not sure if its supposed to say 2 chips or not because my pci v5 isn't in any of my XP boxes right now. The bios at boot says it has a full 64mb and I have flashed it with the last bios available.

It was in an old Socket A Soyo and it did the same things as listed above as well as an Asus P2B with a 350mhz p2. Currently it's in an Asus P2L97-DS. I've tried just about everything and hope someones got some random idea that I haven't thought of.

seems like the card is damaged.