with the exception of the Corperate versoin of XP, when it loads, it takes a 'snapshot' of your hardware profile. If it is dramatically different, it won't load, or it will ask you to re-activate it.

The problems your having is probably related to a bad IDE connection. Check all your cables, try a diff IDE plug/port and then try a new wire. Make sure its all functioning and setup correct.

Reformated, and reinstall the OS when its in YOUR box.