pc BSOD for xp, but will boot vista. [HELP]

hi.

had a look at a friends pc few weeks back. they had win xp, and could only log onto a limited account. everytime i tried to log off and go on admin account it would blue screen and shut down.

nothing i could do to fix it. tried everything.

so i formatted, and installed vista. everything works fine, except i cant find the audio driver for the mobo. aparently, its not compatible so say the company.

so i went to re-format again the other day.
i insert the win xp cd, get through the beginning of installation, and get to where i partition/select where to install windows to.

it shows no devices listed, and as soon as i press any button, it blue screen's again, and re-boots.

its a generic blue screen with no error messages.

i removed the harddrive, and tried a new one thinking it could be that, but the same error.
i removed both sticks of ram and tried a new stick, but same problem.

any suggestions on what i can do?
i find it strange that vista works perfectly, but when i try install xp, it doesnt find a harddrive, and blue screen's.