Took the MacPro to TechRoom to diagnose the problem. They wanted to charge me $50 per drive (x4) to back them up, plus the $50 to diagnostic test. I only opted to have them backup the system drive. They kept it for a week, told me the problem was the original RAM modules. It wasn’t the RAM. It’s most likely the Video card. The computer seems to work fine when I’m not actually using it. Bleh, what a waste of $100.