You are bottlenecked with the 4100. But come on, all the way to 20 FPS? I don't think so, it has shown MUCH better benchmarks than that with lower end cards.
Try this for me; Take out on 560 and run it with a single card. See your performance then. Please post back results.
Well it was a low of 20, sorry for not clarifying, the max was around 40. I took one out and got creamed on ultra.