none??!! Far Cry 2 is multi-core optimized proven by the benchmarks between the Phenom II x2 & x4 @ 3.2http://www.anandtech.com/bench/Product/88?vs=120
and the athlon II x2 and x4http://www.anandtech.com/bench/Product/121?vs=122
so you comment above falls into the epic fail category
You do realize the Athlon II X2 is pulling 45fps and the Athlon II X4 is pulling 40fps in that link right?
I did just notice they added some new games to that bench, and well Dragon Age is the only game that shows any real gains going from 2-4 cores.