It appears as though the Nvidia driver (258.96) has an incompatibility on some faster machines with Windows 7's "Desktop Windows Manager" (dwm.exe). If so, until either Microsoft or Nvidia provides a fix , mine is to go to task manager and stop the "dwm.exe"
process. You'll have to do it two times, as it will not completely shutdown after the first try. That may solve your problem for now. One other thing: I recommend setting Vertical Sync to "ON". (In case you have timing issues,.) In my case it was Zune
that didn't like dwm.exe.(Also, double-check the rest of your Nvidia Control Panel settings.) You should be able to fix it.