Problems booting into XP pro after fresh install on new system

Motherboard: Tyan S2875 tiger K8W
Ram 4 GB reg EEC
CPU 2 x Opteron 244
Graphics ATI Radeon 9600??
1 x 40GB IDE hard drive (have more to add, but not currently installed)

I have recently built the above system to use as a fileserver, but have been having trouble getting it to boot into XP pro after a fresh install. Just Hangs and blue screens at the welcome screen and then reboots.

I have tried other operating systems ( Vista, Server 2008 and XP X64) all which boot up fine. It is currently running Vista Ultimate and seem very stable, but I would rather use XP as I hate vista. Too Slow.

I am suspecting the issue is possibly with the graphics card, but am not too sure on how to sort this other than replace it with a different one. I have also read that there are sometimes issues with ATI cards on this M/b??

Any help would be appreciated.

Regards

Andy