I have the same problem with my new dually sys, I've tried every driver out there, still no luck.
dual xp1600's
asus a7m266-D mobo
gainward gf3 ti200 golden sample
512 registered crucial pc2100
The one thing that manages to prolong the inevitable crash by a few minutes is installing the drivers without nvsvc32.exe (nvidia driver helper service). Hope you have luck with one of the older drivers tho. You can download a lot of em from 3dchipset.com.