Increasing My Fps?

arma and dayz are very cpu dependent. the 7770 is decent for entry level 1080p gaming, on medium settings. you will notice more gain in fps by upgrading your cpu first, and then your gpu later if needed.

do you know what motherboard you are using? i can check compatability for you and recommend a better cpu.
 
the 6350 is the same as the 6300 but its clocked higher from the factory. so if you were planning on overclocking, you might save a few bucks by getting a 6300. if not, it really doesnt make much of a difference.

but yes, that and a gpu down the road is a good idea.

i mention overclocking because you already are, and im assuming you already have a decent cpu cooler.