SirKnight wrote on Apr 24, 2012, 23:41: The tessellation features ATI put in the 360 GPU is not completely what DX11 exposes.
Right... ATi (AMD) had Truform on the PC Graphics Cards since early 2000. I think Return to Castle Wolfenstein was one of the few major titles in 2001 that supported it. It could be enabled with either DirectX or OpenGL.
While it is tessellation... it is NOT DX11 tessellation, and very primitive by comparison.
As others have said... Some of the other features are available in DX9, and some of the features are implemented "in software" (not gpu hardware accelerated)