We recommend using this patch only if you have a high end NVIDIA Graphics Card and your PC meets the Recommended System requirements.
Recommended System requirements:
GPU PhysX effects require: Microsoft Windows Vista, graphics card with full Microsoft DirectX 10 support
Recommended GPU: NVIDIA GeForce GTX260 or higher
Note: Applying this patch will make your previous saved games unavailable. You will have to start the game over from the beginning.
You can find the patch for US (Aspyr) version here
and European (505 Games) version here
. Full list of changes you can find here