Lines of color radiating out of the fish? Sounds great! Where can I get this feature?

OK seriously now... the Geforce256 was indeed the first series and it should work great with the aquarium. Mine is running 85 fps at 1280x1024. I use the "latest" drivers from Asus which are pretty old (v.3.75 april 7, 2000). At first I was pissed at Asus for not updating the drivers like for example Creative does, but since then I have seen that drivers supposedly compatible with all NVidia chipsets only benefit the newest and often screw up older chipsets.
So for a stable performance I would recommend using the latest drivers from the card manufacturer specifically made for the Geforce256 and leave the NVidia detonators alone.