Here is my gaming pc build. I want to play BF 4 and Arma III on high to ultra settings. I want this pc to last at least 3 years. Will this build fit the job? Should I get a Hyper 212 evo for over clocking? http://pcpartpicker.com/p/1QGUS
That's what I think you should get. With some overclocking the 8320 can be as good as the i5-3470 in single-threaded apps. The lower price, however, gets you a GTX 760 which is more powerful than an HD 7950.
I also swapped out your case for something cheaper (basically the same case but without a window - personally I think performance always trumps looks). The money saved from that went toward a better mobo.
by how much in terms of fps? Or are you just an Nvidia fanboy?
See my edit above.
And no, I'm not a Nvidia fanboy. I own Nvidia cards, but that is because they were really the best option for me when I bought them. I recommend GPUs based on the best performance you can get at a certain price point. In your case, that happens to be the GTX 760. If we were talking $50 more, however ($300 price point), I would have recommended the R9 280X, as that is the clear winner there.