I'm trying to install Windows 7 32-bit on an Optiplex 745. The install runs, reboots, says it's finishing the installation, and then the screen loses input and goes blank, hard drive activity stops, and all the fans in the case seem start to climb in RPM/volume until I decide to pull the plug.

I've had a previous problem with this PC crashing, narrowed it down to the RAM and have installed fresh RAM. Windows XP 32-bit seems to install and work fine.

Any ideas? Help appreciated.