I5-3470+670 gtx > i5 or i7 k + 7870.
Get the second option, the i5-3470 is a good cpu for people who doesn't want to oc the cpu, and at stock speeds there's no difference between the two cpus, but at gaming there's a difference between a 7870 vs 670 gtx.
Will there be more of a performance gain depending on if I oc the cpu, or gpu? Or is that just dependent on the game entirely, just how ps2 is cpu dependent, etc?
And the reason I went with the i5 3470 was the fact that I'm on a bit of a tight budget, and really want/need the extra cores for gaming. If an i5 2500k comes on sale, will it be inferior to the sandy i5's? Because I might get that if it does.