Prototype of a PhysX collision demo developed with GeeXLab
FiringSquad has published an article that compares PhysX performance of CPU versus PPU versus GPU. The softwares used for this test are Unreal Tournament 3, Nurien and Warmonger.
Read the complete article here: PhysX Performance Update: GPU vs. PPU vs. CPU
In PhysX FluidMark news, I put a graph that shows CPU/PPU/GPU comparison. The results show a larger difference between PPU and GPU but this is due to the kind of test: fluid simulation.