Originally posted by Kevin Turch
Make sure you 3x check ur bios settings, my A7N8X came with them all screwed up, also make sure the heat sink on the cpu is the correct way, there is a lip that sits on top of the cpu holder that, if not seated the right way, will not make contact with the cpu and cause it to overheat, hence the lockup.rebooting.
Also, get the latest bios update, i had the same exact issues as you with my MB.
Good luck.
Kevin