AMD is working on LiquidVR while nVidia is working on VRWorks. Both of these API’s divide the workload of the graphics among the multiple GPU’s only if the game developer programmed it to use them. With VR, they can have a single GPU render and display graphics to a single eye while having another GPU render and display to the other eye. This division of the workload among separate GPU’s is similar to the DX12 multi explicit GPU technology. I believe Vulkan also uses this method too. These new methods are the reasons why the GPU manufacturer’s have proclaimed AMD’s CrossfireX and nVidia’s SLI as “dead”. Nothing “new” is being developed for DX11 or DX9 which is what CrossfireX and SLI use in order to combine the two (or more) to act as a single GPU. There are some reports that some DX11 titles can utilize the CrossfireX and SLI in conjunction with VR, but not much has been talked about in depth or have examples of them working together.