Agent.X7 wrote on Mar 8, 2010, 21:41: It's not a problem at all, it's marketing.
It IS a problem because it stifles real competition. Nvidia can't yet compete with AMD/ATI on the real merits of its cards (DirectX 11) so it intentionally prevents AMD/ATI cards from functioning with PhysX. And, Nvidia doesn't even allow PhysX to function on an Nvidia card if an AMD/ATI card is in the same PC being used for video.
Consumers are the ones who suffer for it in lack of choice and higher prices for Nvidia cards than they could otherwise fetch in the marketplace.