With the screen packed full I get ~170fps. I'm not familiar with how Chipmunk works, however. The demo won't use more than 1 core, so I'm guessing Chipmunk doesn't operate in its own thread? That would seem odd to me... there should be at least 2-3 threads. (Game logic / drawing / physics) Fairly confident I'm not hitting a GPU barrier at least. As is though, looks like it should be able to make at least a basic physics based game with no problem.