Card name: NVIDIA GeForce 8800 GTS
Current Mode: 1920 x 1080 (32 bit) (30Hz)
Native Mode: 1920 x 1080(p) (60.000Hz)
This looks unusual. Why does your display run at 30Hz?
I don't know if it causes the problem, but i would try setting it to the native 60Hz.
Also, there are two Monitors listed. Disabling one is worth a try.