What's more important is the addition of DirectX 12 support, a low-level graphics API designed to increase 3D graphics performance with lower overheads while giving developers more control over how hardware is used. This is most important for gamers though as most professional 3D graphics software relies on the competing OpenGL API instead. Although it's still very early days for DirectX 12 with few titles currently taking advantage of it, if you're looking for the best 3D gaming performance available the Windows 10 is likely your best bet as DirectX 12 won't be available for Windows 8.1 or 7.