It's not worth getting X79 unless you pair it with a 6-core CPU.
However, I feel obliged to point out that used 3930K/3960X CPUs are now selling for the same or
less than a new 4820K, so you get go X79 and buy a used CPU (I've bought several recently).
But if your main usage is gaming, then ksham is right, a 4790K would be better.
As for the mbd, do you intend to only ever have one GPU? Or do you want to be able to
add a 2nd for SLI/CF in the future? If possible I'd recommend a board with tri-slot spacing
for better cooling.
I specialise in X79 builds, but for gaming I'd go Z97, 4790K, H100i with 4 good fans (eg.
Nanoxia DS 120mm PWM), two GTX 780 Ti, something like the ASUS Maximums VII Ranger
or related ROG board, 16GB GSkill TridentX 2400, 840/850 Pro 256GB C-drive.
Ian.