Last year when I ran the Windows7 compatibility test for my PC. It told me to update to the latest nVidia drivers. But when I checked with nVidia (at that time) they said, that their latest drivers were NOT compatible with Windows7.
But now I hear that they have been working with Microsoft to make sure they are.
When did you download and install your 'NEW' drivers? They may not be new enough?... click here Scroll down for the supported cards.