I repaired a laptop today with Windows Vista, it definitely does NOT have any viruses, root kits etc, system sits at 0% cpu usage. It's an Intel CPU, with a small cool running hard drive. CPU temp is at about 40c. After sitting for a few hours, I have to turn the system off with the power button because the system is not responsive, on reboot, everything is fast and normal. I did a memtest and found no memory errors. Hard drive has 15,000 hours on it and has no errors. Puzzling! Thanks guys!