This is going to sound bizarre, but I encountered a computer exhibiting similar problems. Except I was never able to get the PC to boot with drivers I would install, it would just black out on first try then revert to different drivers. When I took the computer back to the shop, the problems went away. It took several days but I finally figured out it was the monitor, not the drivers. Apparently, if the monitor is not "signed" my MS, you get these problems. I wasn't getting the problems at the shop because I was using a different, and ironically much older, monitor
Unfortunately, I don't recall how I resolved it. I believe it's an MSDN article where you need to force XP to allow you to use unsigned hardware.
Try using a different monitor (not the same model or brand) and see if the problem goes away.