I have been playing quite a bit of company of heroes, fallout 3, GTA4, and also Peggle (probably the most CPU intensive game of them all) lately and it has been bothering me for quite some time that I am never able to get much past medium settings and turn on shadows. I would like something that could handle high graphics settings with AAx2 running at 1680x1050. I have a core2duo conroe @ 2.66GH and was wondering how high I could OC it to still be stable. Like an idiot I forgot to use artic gel when putting in the CPU so all it has is it's stock fan for cooling. I am using an antec 900 case though which has PLENTY of fans. Of course only if OC'ing it is even necessary. Suggestions ?
As far as graphics cards there are many good options out there. Check out the charts on Tom's Hardware for comparison ( http://www.tomshardware.com/charts/ ). 4890s under $250, 4870s under $200, and 4850s around $100 are all great options.
Overclocking is art, not science. It might overclock to 3.2 with stock cooling, or it might not hit 3.0 with water cooling...
