Khronos Group has the technology and gaming worlds excited over its Vulkan API, which is a low-level API that provides more performance from your graphics card in games that utilize the API - like DOOM.
But after their GDC 2017 slides were looked over, native multi-GPU support for NVIDIA GeForce SLI and AMD Radeon CrossFire setups now require WDDM to be set to "linked display adapter mode", something that is exclusive to Windows 10. This means that Vulkan and its multi-GPU goodness is locked to Windows 10, eyeing off Windows 7 and Windows 8.1 users with multi-GPUs, with a striking glare.
Game developers have to add multi-GPU, DX12, and/or Vulkan support in manually - so this isn't too much of a surprise, but whatever Khronos, Microsoft, NVIDIA, or AMD can do to make game developers' lives easier for multi-GPU goodness, they should be doing. This kind of feels like a step backwards.