So right now I have a S939 NF4 Motherboard and I don't feel like doing an entire system rebuild at the moment but I kinda get the feeling that my CPU is getting left behind. Most of the time I will be playing TF2, UT3, and WoW. I took a quick look at Newegg and there aren't many CPU choices out there for my S939, and most of the time I'm not sure if upgrading will even get me any more performance. So what's your take on this? Basically it's between some Opterons (175,180,185) and a Manchester 4200+.