Profiling for Forward Shading VR

We are nearing the launch date for our VR title and I began to profile the CPU and GPU on both the Oculus CV1 and HTC Vive. Both machines we have tested on are very similar.

Oculus CV1 rig: i7-5930K CPU @ 3.50GHz, 32 GB RAM, GTX Geforce 980 TI

HTC Vive rig: i7-5960X CPU @ 3.0GHz, 64 GB RAM, GTX Geforce 980 TI

What I have noticed on the Vive is that the draw thread will jump up to 20 ms, of course followed by the GPU at 20ms (45 fps).

On the Oculus CV1 the draw thread will stay low around 1-3 ms with the GPU around 20 ms.

I’m guessing this is different types of projections on both HMDs.

Why do the CPU and GPU profiling numbers not add up?
Our experience can render under 11 ms but the profilers do not seem to tell me the reason for the drop to 45 fps.

I’ve attached a screen shot to show an example on the Oculus CV1. I am new to this subject so I’m hoping someone can point me in the right direction. Any help would be very much appreciated!

Thank you!