not sure if it has to do with sse2 but apparently the geforce3 doesn't work well with the p4 yet. here's the repeort. i'd include the link to the actual source but it's dead.
"Voodoo5, which was physically incompatible with some of the Pentium4 boards has almost dissapered from the horizon, but it looks like we have a really nice "follower" for it... GeForce3. According to eyewitnesses, a Pentium4 system with GeForce3 is quite unstable, in some cases, even dynamic test could not be passed. Thus some of the manufacturers may delay GeForce3 cards launch and some of them has even declined to make them. We don`t know what is the reason of such behaviour of the card (drivers or a card itself), however, this fact is very annoying.
Probably, NVidia has hastened with the announce of NV20 - it was necessary to wait some time to reinsure from this kind of incidents. It is very funny - a week ago NVidia has informed about Pentium4 and SSE2 optimization for the GF3 GPU, and now it becomes clears that GeForce3 cards can`t work in Pentium4 system properly... I understand, that actually, the drivers, not cards, are optimized, but it it is great when the card simply works
It seems, that there is at least one reason not to send GeForce3 samples for rewievers..."
Source: Reactor Critical