Linux is mostly on par with Windows 8.1... if you’re willing ignore benchmarks
Ubuntu Linux Gaming Performance Mostly On Par With Windows 8.1…
Given the recent release of Microsoft Windows 8.1, at Phoronix we took 13 different AMD Radeon and NVIDIA GeForce graphics cards and compared the performance between Ubuntu Linux and Windows 8.1 with the same hardware and set of OpenGL games/benchmarks. For AMD and NVIDIA graphics cards with their official drivers, the performance is largely similar between the competing desktop operating systems but there are some performance exceptions.
By exceptions they mean nearly 2x the performance gap on the highest end graphics cards stress tests. Linux wins if you consider OpenArena your game of choice.
I’m still sold on SteamBox as the future of game consoles but let’s not pretend that Steam’s choice doesn’t have anything to do with licensing Windows, the Windows (app) Store and tailoring a complete living room user-experience.