Well I've been running this opteron 170 at stock in my a8n-sli premium for about 2 years now and decided to have a play. Now appears to be stable (after admittedly only about 20 min of prime 2004) so far at 2.7Ghz with a divider on the ram to get it running at 450Mhz.

Always intended to overclock it but better late never I suppose, rather happy with the results so far, a 35% overclock ain't bad.