See if you are into mainly office works then go for AMD Sempron 2800+. If you are into serious gaming go for Intel Prescott Extreme Edition 3.2GHz and if you are into digital jobs, designing and hardcore multimedia then go for AMD Athlon 64 3200+.
ive two computers at home and both are amd ... and till now i have had no probs with any 1 ... i am an amd fan(fan as in case of lover ..not the cpu fan ) and i recommend amd processors (preferrably athlon 64 3200+)
currently AMD dual code is best, intel is no where near in performance. if you google search , 99 out of 100 will sugest AMD . here is one more link ,it is very simple,easy and clear to understand.even layman can understand. comparision in single graph of all dual core processor:
*reviews.cnet.com/4520-10442_7-6389077-2.html?tag=lnav
intel sucks AMD rocks, i say this coz i am using AMD duron 800MHZ processor but my friend is using p4 1.9GHZ processor still my processor stands way ahead from intel.