auscanzukus :
Overclocking takes time to stablize the o/c. It's not for everyone.
I think your best bet is a stock cpu & a good mobo. Start with E8400 & ASUS P5Q PRO. Pick out the rest and repost your selection in homebuilt.
arent more apps and games being quad optimized? i know that there are many games that had higher benchmarks on the E*** series over the quad core q**** series... but arent programmers going to eventually shift to the quads?
i mean it seems to me that the OP is a serious gamer .... so in my opinion, he should opt for the quad cores rather than sticking with the dual cores since games are being optimized for the quads as we speak... im pretty sure that the new games coming out will not be coded or optimized for dual cores anymore... if anything, its going to be phased out (this is just my foresight - theres a big arguement going around that programmers wont even go into quad territory for a while - but i beg to differ)
and i highly doubt programmers will even program games based on nahelem... not for years to come anyways... i dont see anyone (anyone on the regular level - which is regular people with regular computing tasks) even buying nehalem or needing it... so my point is that quad cores is the 'sweet spot' for years to come for us, regular people...
so finally....
i recommend x48 board... something like gigabyte's GA-x48-dq6 @ $285 which has crossfire option with both gpus running @ x16 speeds, also the 1600 front side bus will help decrease bottlenecks that gamers often experience
http://www.newegg.com/Product/Product.aspx?Item=N82E16813128331
if you dont want to overclock, and seeing that your budget is fairly high (in my point of view), you mind as well get the fastest stock quad core processor, say for example ... intel q9550 @ 2.83ghz @ 1333mhz front side bus @ $570
hope this helps you decide...