xp install reboot loop at “install

Here’s the situation: I am trying to upgrade to xp pro to xp pro (sounds kinda funky, but that’s what you have to do to change motherboards with xp) I fight through all the hassles and troubles that xp gives me, It starts installing devices, and just as the light at the end of the tunnel seems within reach … my computer reboots. I’m sitting here … “what the heck?” and sat thought the install again… it gets to the “installing devices” screen againand reboots. After a few times I get bored, look for a fix and then, after finding none, come to you guys for help.

System:
2.0 xp+ Athlon
KT 333 Dragon Light
80 gig Western Digital
Radeon 8500
256 megs Crucial ddr

Tried:
Rebooting (many times)
Replacing ram and video card

I‘m ‘bout to give up on xp and use 98… PLEASE HELP!