Pretty much the title..

I built my PC in 2012, right when ivy bridge came out

- i5 3570k running at 4.5GHz

- GTX 680

- 16 GB 2400 ram

I reckon a 980 would be a nice boost in performance, I would get one of them fancy hexacore i7's if i could but I don't have the cash, and if it's between a new CPU or a GPU the GPU wins of course.

I'm thinking about getting this one

Not at all, your CPU is totally fine. The 3570k is quite comparable to modern CPUs like the 4690k in gaming, you won't have a problem with it.

@mb: alright, I was almost 100% sure that it would be fine but decided to post anyway to get your expert opinion :P thanks man.

Keep in mind: Since it's a "K" processor, you'll be able to overclock it when it starts to get outdated down the road too.

@cowsnipers: I already did right out of the gate :P it's running at 4.5GHz.

@onarum: Oh nice! That should have you covered then... Reminds me that I need to OC my processor as well lol.