In the past, I haven't had this problem, but recently, when I'm working on an image, the screen won't refresh unless I move an element. It seems to work for a while if I close CS5 and wait for a while, which is a little odd.
I'm running CS5 12.0 for 32-bit systems. I have a GTX 660 with 2GB Ram. I've tried disabling OpenGL and updating my video card drivers.
First, make sure you have all the CS5 updates installed.
Beyond that, updating the video card drivers from Nvidia's website would be my only other suggestion.
Working now. Not sure if it's just because I haven't used it for a while, or if updating to 12.0.4 fixed it.
As a Best Buy employee, I feel really silly that I didn't actually do all the updates. I am the worst at technology.