Yes, thank you guys. 4770 was a typo.
Installing the new catalyst driver 10.4 worked. No problems now.
edit: I also get this problem. My screen will shut off for 1-2 seconds, then it will pop up again. In the lower corner it says "Displayer driver AMD driver stopped working but has recovered successfully."
I'm using the new 10.4 catalyst, so what could cause this?