NVIDIA has removed the latest ForceWare 196.75 from their servers because this driver has an important bug: it prevents the fan from spinning and caused a death of multiple graphics cards around the world.
G92-based graphics cards (GeForce 9800GT, 9800GTX and GTS 250) seem to be very affected by this bug.
I currently use this driver on a EVGA GTX 295 / Win7 64-bit without issue.
So in case of doubt, NVIDIA recommend to use ForceWare 196.21. But this driver has a bug and prevents the overclocking of GPU 😀
So the recommended driver is the ForceWare 196.34.
Le jour se lève et les conneries commencent 😉
R196.75 were also the source of artifacts in my OpenGL apps. See HERE for more details.