Cpu and motherboard Combo? Or new GPU?

So,  Im running an i3 3220, and a gtx 580.  I want a little bit more.  So, i can get an 4820k (Need X79 features) and get an evga x79 classified.  Or, I can get a 680.  Not going to get a 770, I like the fact that it once was a flagship card XD.  What would give more performance?  I play lots of indies(rust, limbo, trine 2, and others), but also some major AAA games like BF4, GTA 4, Skyrim (Modded of course) and countless others.  Most of the poorly coded indies get down to 30fps and lower on max settings, and so do some very intensive ones like bf4, and skyrim modded.  I have a 3gb 580 now.  


The CPU I'm pretty sure would bottleneck the 680 or 770.