witcher 2 crashes my display

hi.

i bought the witcher 2 EE from steam and playing seems to cause a lot of trouble for my graphics card. it crashes my display driver a lot and occasionaly causes a complete system freze requiring me to force the computer to shut down. so far it's only happening with the witcher 2. my graphics card is a gtx 460 768 mb OC'd to 850Mhz, and i upgraded to the latest driver

I have a GTX 285 and am experiencing heavy graphical glitching also. It ran flawlessly when first released, now I can't even play. I want to install the latest drivers, but the Nvidia site fails to auto-detect my card nor does it find any 285 GTX drivers even if I manually select them. Now I don't know where to get them. Christ if I can't get them from the damn manufacturer's website....