Pettervu, I was surprised to get an alert on this old post. I should have documented the solution better. My recollection is that I had to download the ATI driver "suite" (then called ATI Catalyst Control Center, now AMD Catalyst Control Center), from the computer manufacturer's web site. The download from AMD's web site wasn't compatible with the OEM hardware.
As I recall, everything in that package has to be of the matching version number. I tried replacing just the atipcie.sys with one I found online and it wasn't compatible. Uninstall the existing CCC (I think I did that from Windows Control Panel, uninstall programs), then install the replacement.
That's as much as I remember. The episode drove me nuts for days and I...