Get a Motherboard that supports C.O.P. (CPU Overheating Protection), I run the asus A7V333 and COP saved my ass once.
Also you cank eek more performance off your AMD chips with a great HS/fan combo, I run an SK78 Pro from 3dcool.com, unfortunatly that fan was fased out, the SLk800 is a nice one though
http://www.3dcool.com/?module=product&sku=SLK800