Upgrading CPU

[nikkob]

Hey i was looking to upgrade my CPU for games to play such as Diablo 3. I can run at a smooth 60 fps, but once i jump into co op, it becomes a little annoying dropping down to around 10-20 fps during an encounter. I upgraded my video card to a Nvidia GTX 560 Ti not to long ago and it runs very nicely, but im assuming a game like Diablo rellies mostly on the proccessor for mathematical information. So my question is, what is a cpu I should look into buying with a fair price?

Spec: http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01643511&tmp_task=prodinfoCategory&cc=us&dlc=en&jumpid=reg_r1002_usen&lc=en&product=3856272

 

[DJDeCiBeL]

If you already have the Phenom X4 9550 (like it says in the link) you're pretty much maxed out on the CPU upgrade options for that mobo. A X4 9850 is the best you can do, but that wouldn't really be worth "upgrading" to for only a 300Mhz difference.