With regards to core-for-core processing power, Intel is on top, performance-wise right now. BUT - the prices of Intel's offerings are pretty ridiculous. If you're talking price-to-performance, then AMD wins, hands down. You can grab an 8-core, 3.6GHz AMD FX-8150 for $199. Hell, you can grab the 8-core, 3.1GHz FX-8120 at $150 and overclock that sucker. Those things overclock like beasts. Benchmarks will show that Intel's offerings beat out AMD's, clock-for-clock - but the margin is virtually negligible. There just is NOT enough of a difference between the power of Intel and AMD's CPU's to justify the huge premium you'll pay for going with Intel. I mean, seriously:
If someone absolutely NEEDS to have the very best because they get off on synthetic benchmarks, and because money is no object for them - then by all means, they should go with Intel. But if you want to be smart and get 90+ percent of the performance you'd get with Intel at a fraction of the cost, then you'll go with AMD.
Also to the OP, I wouldn't go the AM3 CPU on your AM2 board route if I were you. As someone stated, you won't be able to use DDR3 memory and your AM3 CPU will be limited to the AM2 hypertransport speeds. You'll be crippling the CPU's capabilities by limiting it to a slow bus and cause bottlenecks. Imagine a car has this very powerful engine - something from a race car - but the transmission is from some old minivan: sure, the car is capable of going very fast because it has a great engine, but the transmission is just too old or slow to properly transfer that power to your wheels.
This post has been edited by HeartAttack: 25 May 2012 - 07:42 PM