Advice on upgrade

Welcome to the forums Jim,

With the exception of your GPU, you have a good gaming rig.

The CPU is great for gaming and while there are quads, they won't bring you the returns you're looking for considering the cost.

Windows 7 can increase performance in games as it supports DX11 and shouldn't be too long before games start shipping that use it. I'm guessing you have 4 gigs for ram installed, which is enough for gaming, but you would have access to all 4 in Win7 64bit. So that's a good choice if you're upgrading the OS anyway.

That leaves the GPU. The P35 boards use PCIe 1.0 x16 slots, which work at the same bandwidth as PCIe 2.0 x8 slots. The heaviest GPU I'd put into that mobo is a 5770 or stretch it to a 5850. Anything more would saturate the bandwidth and you're paying for more GPU than you can use. To give the best recommendation for a GPU, can you list the resolution of the monitor you are playing on and also the power suppy and case you're using.

I'd recommend the 5850 for that resolution if you want detail levels higher. You can get away with the 5770 with some details not at high. That will depend on the games you play. The catch though, the 5850s sell out quickly when inventories do come in.

5850 zzf in stock
http://search.zipzoomfly.com/?Key= [...] 00&x=0&y=0

5850 newegg out of stock
http://www.newegg.com/Product/Prod [...] 50&x=0&y=0

5770 instock at newegg and zzf
http://search.zipzoomfly.com/?Key= [...] 00&x=0&y=0
http://www.newegg.com/Product/Prod [...] eo%20Cards

The only other component that can really effect some games is stepping up to a SDD. I'm not the one to really ask on those, but if you play MMOPGs, it can help alot when there's a lot of avatars on the screen.

If you want to try your hand at overclocking, that CPU should get to 4ghz on air with a good aftermarket cooler. Might help a touch with games.