One of our forum members has discovered something really interesting... that’s what he wrote on our forums:
“Well for all those who have used Nvidia cards for PhysX and ATI cards to render graphics in Windows 7... All that is about to change.
Since the release of 186 graphics drivers Nvidia has decided to disable PhysX anytime a Non-Nvidia GPU is even present in the same PC. Nvidia again has shot themselves in the foot here and showed they are not customer oriented. Since they are pushing Physx this will not win over any ATI fanboys with this latest decision.” He also posted an email from Nvidia confirming his discovery."