[*]About what does the Physx when a dedicated card isn't there, I believe all those calculations are done on the GPU, and the CPU doesn't do anything about that. The only time it does use the CPU is when a CUDA-based GPU isn't detected. With that being said, I do plan on OC'ing my CPU more to ensure it's not as much a bottleneck in general (current OC at 3.75GHz).
Btw, I'm actually going to post more results, but run the benchmarks in 3D to see if that has any difference as to what's going on right now.
2. I predict, turning on 3D will cut framerate by 50%