GTX 670 + 3570K
a 3770K can perform under a 3570K if the game doesn't like hyper threading enabled. With it disabled it gets equal fps as the 3570K.
For gaming a 3770K is $100 more than what you need from the CPU since the 3570K = 3770K minus HT.
Save yourself $200 get the 3570K and 670 and get yourself a nice set of speakers or a new monitor or a new mechanical keyboard with the money you saved
People think you need an i7 just to "multitask" those same people think its better pay $100 extra for the label i7 than for the i5 because "i7 > i5" numerically. lol.
I multitask like crazy with my 2500K and still manage to game at same time. Magic.