Please Help P5N-MX

Ok well, I just bought a Radeon 4870 512 gfx card and I am seeing like 15-30 fps while playing (get ready for a lol) World of Warcraft. I have talked to several people and they say that its my processor bottlenecking. I have a intel e2180 2ghz cpu and a P5N-MX mobo. So before replacing my processor I would like to attempt to overclock it. While in the bios settings I dont see any option to actually change the fsb of the cpu. I have 2 gigs of DDR2 800 memory and I do see an option in the bios to change fsb but its set at 800 mhz already so im assuming thats for the Ram itself not the CPU. Any help on how to OC with this mobo would be greatly appreciated. Thank you in advance for your time.