So yeah, this little demo, with its rudimentary graphics, takes 2x1080 in SLI to render, presumably 1 for each eye. There's also another 1080 for PhysX.
And this is with, presumably, all the exciting Pascal-only VR technology that improves performance. If this is the kind of computational power needed just for rudimentary VR then I wonder how the hell is Polaris gonna bring VR to the mainstream?