I recently reformatted my girlfreinds computer that wasnt working properly and re-installed windows xp, drivers, ect. So the computer is at my house and working perfectly. So I bring the newly fixed computer back to my girlfreinds house and hook it up and turn it on. As soon as I turn it on the 'spalsh' screen is all distorted, like a few inches of lines are missing and blinking above, but this is all over the screen. The computer still boots up and you can see the text is even all screwy, but when the windows desktop should be showing it goes back the the mother board spalsh screen with all the distortion and just sits there. So I reboot, again and again, no luck, take the cover off and clean all the dust out, check and re-check all the cables ect. No luck .
So the weird thing is it worked fine at my place and not fine there. Could the cable from the video card to the monitor be screwed up? Could it be that there is no real "ground" in the electrical system at my girlfreinds house (it is an old house). I have also noticed before I fixed my GF computer the screen every so often would ficker these lins of distortion - thats why i am thinking a buggered up video cable?. Or do computers 100% NEED a ground to function properly? (I am not concered about saftey at this point - I am an electrican).
The computer it self is an intel P4 2.60GHZ 768 ram, Intergrated video card radeon 9100 IGP.
Any insight in this problem would be greatly appreiated

Reseat the graphics card and anything that might have been jarred during transportation.

At a basic level the electrical ground should not be a factor as to this issue.

Also check the location near any magnetic source such as large speakers etc.

If it is a CRT monitor hit the Degauss button.

Ok the graphic card is intergrated, so it cant be reseated.. but I did clean out the dust
there is no magnetic sources close by
it is not a crt its a flat LCD

Does it work OK in Safe Mode?