The official GT300/Fermi Thread

[Farinorco]

both ATi and nvidia use software tessellation for dx11. it is superior to hardware tessellation because of performance per transistor. so technically it does support d3d11. fixed function is only useful for ROPs.

AFAIK, Radeon HD5000 series cards have a hardware tesselation unit which makes all the fixed function tesselation work. They started to develope this as soon as they knew it was to be a main feature of DirectX (formerly DX10, then delayed until DX11), when they were designing the XBox 360 Xenos chip. Of course, the final DX11 version is wider than the previous one implemented by ATI (AFAIK, the DX11 tesselation is a superset of ATI tesselation), so previous ATI cards are NOT compatible with the new DX11 tesselation.

A dedicated hw is always more efficient in doing the speciallized task it is built for than more generic, flexible and programmable hw. You are going to use more transistors to do a task if those transistors are from a generic processor than if they are dedicated (especially designed/optimized to) to do that task. The advantage of using more generic hw, is that it can be used for different things (so if there's no need to do that task, there are no wasted transistors), and that you may balance the work load the way you want.

But a dedicated, specialized hardware for a task, is always going to be more efficient at doing it.

The question is... ¿has Fermi also a dedicated hardware to solve the fixed function tesselation, or it hasn't? If not, how big of an impact that means when the chip has to resolve tesselation, when compared with a chip with dedicated hardware to it (Radeons)?