Video games supporting hardware acceleration by PhysX can be accelerated by either a PhysX PPU or a CUDA-enabled GeForce GPU, thus offloading physics calculations from the CPU allowing it to perform other tasks instead, potentially resulting in a smoother gaming experience.
So your GPU is utilized to compute physics models, using variables such as mass, velocity, friction and wind resistance. It can simulate and predict effects under different conditions that would approximate what happens in real life or in a fantasy world and then translate that into video games.
Most GeForce series 8 and higher graphics cards can handle CUDA. And as such Series 8, 9 and GTX 200 graphics cards can be utilized for NVIDIA PhysX processing.
Once once you start using this feature you will forfeit some of the overall performance of the GPU. On your average GPU this is roughly 10 to 15%
That's why in the future you could use your older CUDA ready graphics card as an add-on, and use it as a physics card while your shiny new graphics card can render the game. The idea, although not definitely new, is an interesting one.
This month a new patch is distributed for two new games as well, Sacred 2 Fallen Angel (RPG) and Star Tales (social networking game). We have some videos from Sacred 2 Fallen Angel and Star Tales showing off PhysX.
Mind you that the videos are provided by NVIDIA, thus are showing the cherry picked effects and have a logo or 50 too much in them.
Check out the effects in Sacred 2 Fallen Angel - Hint select HQ in the Youtube video.
Above you can see Star Tales. What you need to focus on is the cloth simulations. These are GPU Physics based.
So while it is hard to explain exactly what PhysX can do in your games I will give you a few examples. Imagine cloth or flags moving fluently, dynamically created force fields with changing geometry, when you shoot at stuff, loads of debris.