The only thing I can think of is that your cpu might be bottlenecking your system a bit.
Now for your games not going over 60 fps... the reason is that in your graphic settings in your games you have vsync turned on which limits your frames to your monitors frequency. For example your monitor, like most, is 60hz so you'll only get the 60fps... with vsync on. Turn it off and your frames will go higher but you always run the risk of getting screen tears, which is what vsync prevents. Or just buy a 120hz monitor and then you'll be able to get higher frames.
Do you have 4 sticks of RAM? If not, you're operating in single-channel mode, which reduces performance.
Your CPU isn't the strongest, and you will see drops in your framerate when there's a lot going on or a huge draw distance because of that.
Far Cry 3 is incredibly demanding, and the best advice would be to turn off MSAA.
As for the other two games at 60fps, it may be capped in-game, or you may have Vsync on. Either way, you are right - you will not see the extra frames if you go over 60, so be happy you're maxing out the game.