Your CPU is fine. Unless you are going to run 2 of those cards in Crossfire... no need to overclock or upgrade the CPU. If the CPU is a bottleneck at all, it will only be by 1-2fps. Don't worry about it.
If there is something you cannot play at a comfortable resolution with the most desired settings, you can overclock the CPU in baby steps and retest the settings... but most of the graphics processing is in the GPU, not CPU.
The CPU runs the game, it's AI, multiplayer interfaces, higher effects of reflections that your GPU can't do, and also can help scaling the resolution if your GPU can't cope. That is why people worry about a bottleneck. If they cannot play at a comfortable resolution with desired effects, sometimes the CPU is to blame. But your CPU is still a good one. http://www.anandtech.com/bench/Product/56
As you can see from that link, your framerates will still be acceptable in most cases. For Far Cry 2 it seems a little low, but great in Crysis and Left 4 Dead.
Don't worry about it.