I was in a very similar position to yours and also opted for just a GPU change and just going to a GTX 780 from a GTX 580 doubled or more my FPS in virtually every game I own.
Since the i7 I think CPU's have hit a kind of block where previously to get more performance you "had" to upgrade. It seems that if you're getting speeds of 4Ghz+ then the CPU isn't the issue and simply fitted a SSD and newest GPU can massively increase the life of your PC.
Since the i7 I think CPU's have hit a kind of block where previously to get more performance you "had" to upgrade. It seems that if you're getting speeds of 4Ghz+ then the CPU isn't the issue and simply fitted a SSD and newest GPU can massively increase the life of your PC.
