Actually it works just fine when you're using Nvidia 8800
series. You can use the Nvidia 400 series but I'm not sure how well it works with AMD/ATI cards.
The annoying thing when running PhysX with an ATI card is whenever you update the ATI driver, you need to reinstall the PhysX driver (this is highly recommended
). If you do not do this, you will run into annoying problems & then you will start to complain