Can't run the game

[loftar]

OpenGL is good, but it's not well supported on desktop graphics cards unless you own a Mac.

Sorry, but this isn't true either. :)

It may be true if you're using Microsoft's built-in drivers (which you shouldn't do in any case), but at least nVidia seem to be quite committed to their OpenGL implementation, and it is well-published that eg. Valve has found their engines to run faster on OpenGL than Direct3D when both have been compared on Windows.

It was true quite a while ago that Direct3D had an edge over OpenGL back when the ARB was still the governing body of OpenGL, but since Khronos took over, OpenGL and Direct3D have been competing head-to-head even on Windows, and that was quite a long time ago by now.

[MagicManICT]

Then I'll stand corrected. Even just a couple of years ago it was the case, and I'll be honest that I haven't kept up with latest generation of cards quite as well since my interest in it has declined. However, is it just Valve making these claims, or is everyone working on it? (I'll note I clearly recall a time when DirectX was just a glimmer in Microsoft's eye and nobody would use it due to lack of performance.)

From my limited experience working with OGL, and you're statement on the changes, loftar, I'm going to say my statement holds true for older versions unless the gpu manufacturers are optimizing for older versions of OGL. (I don't see why they would be... would be like asking them to optimize for Glide.)