4000+ or 4400+

well im going to be getting my gaming rig soon and what woulkd be better play gaming bf2 and all that on high and i want something that is going to be able to play all thes game on high say 1 year down the line

The most important thing is going to be the video card. X1900XTX is what I'd recommend.
Regarding CPUs, if you can afford a dual core, then there's no reason to go single core is my moto.
Might want to get an Opty 170, its a 2GHz chip, OCs like mad and will cost you a lot less.

The way I see it... there is no point in buying a top-end chip since the lower-end chips tend to overclock to about the same speed.

Opteron 144:
http://www.newegg.com/Product/Product.asp?Item=N82E16819103600

I see threads all the time where people have these over 2.8GHz on air cooling.

For dual core, it may or may not be worth getting a 4400+ over a 3800+, and certainly is not worth getting over an Opteron 165 or 170. The extra cache (vs 3800+) will net you a few percent in the best case scenario, but it won't be noticable. The Opterons should overclock better, AND have the extra cache.

You either get a 144/146 Opteron or a 165 Opteron.

144 + X1900XT >>>>>>>>>>>>>>>>>> 165 + 7800GT or something along those lines