Quote Originally Posted by ua=42 View Post
DirectX vs OpenGL performance.

DirectX with games on windows usually perform better because the game engine usually (not always) has more optimizations for DirectX than openGL. If properly optimized, they will perform similarly (see valve's lfd port).

There are plenty of examples of unoptimized ports, I've personally dealt with NS2. In NS2 I can get 200fps with DirectX9, but with the OpenGL renderer I will only get 80-100 fps with several options turned down. I also get about 100fps with several options turned down with DirectX11 for the game. The reason is that these are new render modes for the game and they are currently both buggy and unoptimized, while the directX9 renderer has been continuously optimized over the last 4 years.

It is not the fault of the graphics drivers if the developer does a bad DirectX to OpenGL port.
It's not about whose fault is it, it's about end user results. We need benchmarks that use the default graphics stack for a platform/game. If a game targets DirectX primarily and is optimized for it then it should be DirectX that is used for the benchmark, not the unoptimized code that targets OpenGL. End users don't care whether DirectX or OpenGL is used, they only care about end results.

Speaking of end user results, this guy made a quick comparison for Metro:LL between Windows and SteamOS and it seems it's performing pretty much equally on both platforms, which is great to see (scroll down to the last video):