Will upgrading my CPU work successfully?

I have everything upgraded on my computer except for my CPU which is 5 years old. My current cpu is AMD Athlon 64 X2 Dual Core Processor 3800+ 2.0 Ghz. I want to upgrade to this new CPU called, "AMD Phenom II X4 955 Black Edition AM3 CPU HDZ955FBGMBOX - 3.20GHz, Socket AM3, 6MB Cache, 2000MHz (4000 MT/s) FSB, Retail, Processor with Fan". Would it install and operate correctly on my computer? Im upgrading by the way because my current FPS while playing video games is very low and I'm uming its my CPU because everything else is well upgraded.