Bottlenecked. New CPU advice.

Ok.

I just got an XFX 8600GT. Already I noticed it's not performing right (Choppy Low FPS, Low Benchmark scores) which I had a feeling it wouldn't given my CPU sucks. (P4/520 @ 2.8Ghz) I had planned on getting a new CPU anyway but money is tight. I have one in mind, just wanted to get someone else's opinion.

Budget on this is tight, I don't want to spend anymore than the price of this CPU. http://www.newegg.com/Product/Product.aspx?Item=N82E16819103759&Tpk=N82E16819103759

Open to suggestions.

Thanks.
:major

 

well you listed an intel cpu but linked to an amd are you changing mobo's too?

 

Yeah, I am actually sorry.

http://www.newegg.com/Product/Product.aspx?Item=N82E16813131072&Tpk=N82E16813131072

 

that board and chip should do great.I've used dual cores for the last year or so and they really do well.