Is your comp. a DELL by chance. If it is you need to get the updated drivers from DELL and not ATI.

My comp. is a DELL and I found this out a couple of months ago when I did video driver updates from ATI. I had to uninstall the ATI drivers and install the DELL drivers for my video card to work right even though the video card is made by ATI.

Don't ask me what the difference is I have no idea, but everything straightened up with my video card when I installed the DELL drivers.