I'm running a Gtx560 and a Phenom II X4 965 at stock and I'm getting 45-60 fps in Far Cry 3 on High at 1920x1080. If I understand what you are saying you are not seeing the results you should, from my experience.
Sadly, I'm a but of a novice, so find the problem is best left to someone other than me.
my x6 and 6770 plays high for bf3 at 35 with drop to 25 not often but def playable, so i get that on low settings ur quite upset lol
possibly ur drivers? maybe the x4 is being underclocked? monitor the gpu and cpu usage and see if the cpu is running at its 3.2ghz while gaming. Also whats ur ram? id say 4gb would lower fps and quality of play but 6gb+ shouldnt be an issue
I had a Phenom II x4 965BE overclocked to 3.9GHz and I still got fps drops in Arma II and DayZ. I'm telling you it's the CPU and it is a bottleneck. (I should note I had a 1GHz GTX 560 TI at the time and upgrading to a 670 did almost nothing to improve the fps). Not trying to be mean but it is a bottlenecking issue courtesy of the Phenom, switching to a 3570k alleviated the bottleneck for me. I'd recommend either saving up to upgrade or just disable anti-aliasing to try and boost the fps. I mean this is the nicest way possible, Phenoms are becoming outdated for demanding games like Arma, BF3, and Crysis, sorry.
the heirarchy chart puts the 965 right with bulldozer cpus and the higher end apus, which arnt great cpus but should be able to throw out decent fps with a higher end card, and at low settings shouldnt get worse when going to medium lol Maybe there was a bottleneck at higher settings but hes getting bad fps on low and medium presets lol
Arma II isn't optimized very well it seems, or else it's just extremely CPU intensive. I can't advocate for the Phenom x4 series any longer though. The x6 series is a bit stronger but not much. IvyBridge and SandyBridge have taken over the performance charts, with bulldozer and piledriver slightly behind. The Phenoms just can't compete in a modern market anymore in more demanding titles, and that's the truth.