10.04.3 Hangs and Reboots when switching out and in to GUI Screen

[H in OH]

Hello,

I am trying to install 10.04.3 LTS on a system with an Intel Xeon E3-1225 CPU and built in graphics from the Xeon. I have to add a driver from a USB stick for the Adaptec 6805 RAID card, so I switch to a text console with CTRL+ALT+F1 and follow the instructions for copying in the kernel module that I need. When I switch back to the graphical installation with CTRL+ALT+F7, the system completely freezes, the mouse pointer won't move, and after a few seconds, it reboots.

As a test I tried switching at the first screen that appears with the CD boot before even choosing to install (the screen with the "Run Ubuntu Live" and "Install Ubuntu" button choices). All I did was press CTRL+ALT+F1 and then CTRL+ALT+F7, and it still froze and then rebooted.

Any ideas on what would make the installer freeze and reboot when switching screens?

Thanks.
---H

[H in OH]

Removed all components except the motherboard, and replaced the monitor and keyboard, and it is still causing the same problem during installation. No problem switching between multiple text screens. Any attempt to switch back into the graphical screen after switching to a text console will lock the system and eventually reboot.