I was wondering if its worth it to go with a intel core i7 4770k even if i have to switch out y motherboard, or would it be better to just go with a i7 3770k and just stick with my current motherboard. I currently have a nvidia gtx 660 and an intel core i3 2120 processor. Im running games like arma that are very cpu dependent and id like to be getting 50-60fps on maxed graphics.
If your motherboard will support an i7-3770k, go ahead and upgrade to that. While the new features baked into the 4770K are nice, it's not a huge upgrade from Ivy Bridge, so no need to go replacing your motherboard for such little return.