1) Are those temps at idle or under Stress testing (if under idle, don't overclock until you adress your cooling situation [too high for idle!]).
2) Are you trying to overclock or just increase your overclock??
3) The AMD doesn't recommend over 70c for the max temp... http://www.cpu-world.com/CPUs/K10/AMD-Phenom%20II%20X4%20945%20-%20HDX945WFK4DGM%20(HDX945WFGMBOX).html
57 C is at 3.55GHz, when all four cores are working, but not stressed; using stock cooler
When stressed the cpu, temp went up to 67C
I contacted AMD thechnical support, they said max temp is 72C.
Since that time I installed CoolerMaster Hyper 212+ and now it runs at 3.61 GHz with 56 C.
Thanx for the advice, I was in Florida that is why I was slow in replying.