Well id say buying an OEM 3200 on these forums, which sell for like $100-$115 shipped now would be the best buy.
However N7 is right, opterons are better with extra cache and the fact that they OC to like 3ghz fairly easy. However, they also go for around $150 and are going to be a bit hard to find right now.
I would say if your friend is going to be buying one in store new, go for the opteron. They cost almost the same new now... so its almost a moot point. Opteron has more cache and OCs easier and higher.