I'm gonna need a sweeper
From what I can find your current GPU setup, if it scales well, it's still behind a single GTX 660. Not sure how much money you want to spend, but going to something like a GTX 760 would blow that old setup away with much less heat and power consumption. A GTX 770 would be even better if you don't mind spending the extra. I'd also suggest an SSD and switching to a proper RAM kit rather than the mixed arrangement you currently have - although RAM isn't that cheap still.