I think if you want to overclock get the opteron 144, but if you plan on not overclocking get the 3700+. Advantages of opteron is high overclockability. 3700+ runs at 2.2 i believe wont over as high but probably runs alot cooler than the opteron. But IMHO i think the your better off with a 3200+ venice mines does 2.6ghz 1.5v. Im am upgrading to dual core opterons,but if it doesnt overclock high enough, i'll get X2 3800 because they run alot cooler. Save yourself the money and get a 3200+venice rev E overclock it to 2.6-2.8 depending on your setup. If you want opteron, get a 146 instead of 144 or just go dual core. I ran both opteron and athlons and find that athlons general are equal in real life performance to opterons of the same speed. Not a huge noticeable difference. GO for whats cheaper!