VR Updates - 30 NOV 18 News
keep in mind the perf increase from vulkan comes from offloading all the graphics work to the developers and app rather than having dx11 do it.
this means the developers have the opportunity to optimize their code and graphics routines, and most will, but vulkan itself does not guarantee a faster app.
some show large improvements, some barely any. with time and effort, most games will fall somewhere in between.