OPTERON 165 definitey of if your going to OC, dont even think about the 4200+, its garbage. heres a suggestoin, between now and when you order, read A LOT about OCing, then buy the Opteron 165, and u can get it to minimum 2.4GHz on stock cooling, 2 guys here got theirs to 2.8Ghz on stock cooling, you can go higher on liquide cooling im sure, probably past 3GHz.