My brother built a new computer based around a new processor and motherboard, (intel Quad-core Q6600 and Asus P5E), along with a new case so it would be compatible(Antec 900). After transferring over these new parts along with the necessary older parts the computer works fine except for one problem. Everything powers on, the computer gets past BIOS and then goes to boot windows but instead he gets:

"Windows Error Recovery"
Windows failed to start. A recent hardware or software change might be the cause.

If windows files have been damaged or configured incorrectly start up repair can help diagnose and fix the problem. if power was interrupted during startup choose start windows normally.

Launch startup repair(reccomended)
Start windows normally

Whenever he starts windows normally he gets the blue screen of death and an instant restart. If he launches repair it goes to a loading bar that completes in about 5 seconds then just sits at 100% and does nothing.
P.S.
We do not have a copy of windows vista, it came installed on the computer and we never recieved an actual copy.
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To Tina G
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He cannot get to the actual desktop to do any of that from, windows will not launch.

I want to install a new clean OS of Windows XP on my computer.

How I usually do it is to boot from the OS CD then format the Hard drive then install a new Windows.

To do this i usually would change the priority boot sequence and put the CD-ROm Drive first… but this time it doesn't work?

I have the motherboard
INTEL D865GLC

It happens like this on all of my computers running this motherboard.

The computer will boot off the CD ONLY if there is no operating system currently on the Hard Drive.

But there is and and want to REdo it.

Is there a way to fix this, or is there another way to format the hard drive and then install a new OS?