Hello Dantcm,
I'm not aware of any such charts, and I could possibly see why. It would be fairly hard to graph out just exactly how much a video card can stress out a CPU and other components because it also may depend on how the application utilizes such resources. For example, one video game with ridiculous visuals may be written better, or have better drivers, so it processes better than another combination on possibly another application.
I could speculate that you would probably end up bottlenecked by something not named 5750 in your system ; ) (Depending on what you're using your system for, at what settings, etc), but I wouldn't know which part. Could be your processor, could be RAM, etc.