When I run Skyrim in full screen mode, all I get is a black screen. I can hear the intro music, but there is no picture. If I run the game windowed, it works.

My video drivers are up to date. I had mods installed, but removed them all, and then clean installed Skyrim. I am running cross fired Radeon HD 7950s. Turning off cross fire makes no difference. I also tried alt-tabbing to no avail.

Any thoughts?