VR requires very high framerates, and AMD processors have trouble delivering that due to their poor single threaded performance. For a lot of games you're going to have a hard time staying above 90FPS regardless of what GPU you have, even with your CPU overclocked. Future games with DirectX 12 support might improve things for the current AMD offerings by spreading out the driver overhead and not restricting the draw calls to a single master thread which is where the AMD processors get really bogged down. As it stands now with DirectX 11 titles, you're probably out of luck unless the game you are playing is very light on the CPU.