 In addition to common criticisms against Digital Rights Management schemes, there has been speculation that this scheme has been motivated by the fact that it would affect official free/open source graphics driver support by manufacturers.The scheme relies on the internals of graphics cards to tell whether the hardware is trustworthy (permitted to play copy-protected content).This could be subverted if an attacker knows certain details about the hardware's operation, which could be disclosed by hardware documentation or open source device drivers.