Just this past weekend I had to format and reinstall 2 client machines... I backed up their data onto one of my machines and while doing so I decided to do windows update on my computer... there was an ATI display driver update that Windows update wanted to install for a while now, and I figured WHY NOT GIVE IT A GO just for gits and shiggles.
Anyway, my Windows 7 RC tanked... I could get to desktop, but the screen would go BLANK within a short amount of time. LAST KNOWN GOOD CONFIG, SAFE MODE, nothing would help... SAFE MODE worked, but I couldn't uninstall ATI stuff from CP in Safe Mode. System restore only gave me a day prior to restore to, and still that didn't fix the problem.
I'm not sure if it was the viruses on the client's data that I was backing up, or if it was the ATI update from within Windows Update, but even my keyboard wouldn't respond to the machine when the screen was blank. I always hit CAPSLOCK as a test to see if the CAPSLOCK light turns off and on...
I will never trust Windows driver updates again. I could be wrong and the problem may have been a virus on my client's data, but I've had issues with Microsoft's driver updates... I'll only do them if I have NO OTHER AVENUE.