I have a Dell Precision with:
Dual Quad Core Xeon Processors
I have been trying to CLEAN INSTALL windows 7 64bit or 32bit. Ive tryed both but neither seem to work. I've made a bootable USB with both iso's. I've burned both iso's to DVD's. With every try to install it i get the same results. It gets past the "windows is loading files" screen, then once it gets to the "starting windows" screen the 4 orbs show up start to make a circle and freeze. It doesnt go any further.
Couple of things can cause this, the easiest to check is RAM and hard-drive, try variations of both. If that does not get you fixed, see if it starts in Safe Mode. If that does not start either, or starts but locks up soon after, may need a motherboard replacement.
I worked with an HP workstation that did this with every operating system, it would install but crash soon as it tried to start. XP, 7, both did the same thing. HP replaced the motherboard, fixed the issue.