BuckeyeFPS :
its going to be a gaming rig but it needs to be able to handle Battlefield, Call of Duty and such with no lag and the processor im looking at is a AMD FX-8120
Quad-core. No game currently uses more than 4 threads, and I highly doubt developers will use more than 4 threads in their games for at least 2 more years, if not even longer than that. Running an 8-core for gaming is basically only using the half the processor. However, if you want to also record your gaming with Fraps or something similar, having 6 or 8 cores is useful, because Fraps can utilize those inactive cores without taking any cores away from the game. You'd likely notice little to no drop in FPS when recording with Fraps with more than 4 cores.
But that ability to record while playing with no decrease in performance has to be worth the extra $100+ to you. Personally I'd suggest the best-available quad-core on the market.