Low CPU and GPU utilization with Vsync disabled, in blank scene GPU Usage "other" spikes to ~20ms

been working on optimizing a scene when I started finding it odd that I could not hit 144fps with my set up (gtx 970 SLI + i5 4670k)

upon looking into the profiler, i'm noticing lots of spikes of up to ~20ms on the GPU. SO i simplified the scene down, eventually going so far as to make a new scene with no scripts, only an camera, light and cube. Spikes are still happening.

-Sli has been Disabled -vsync turn off in Unity -Forced Vsync off via Nvidia Control panel -Updated to latest graphics Drivers -restarted computer and unity -created whole new project with no imported assets -tested both forward and deferred rendering -disabled AA in game view -disabled all shadows -switched from standard to mobile diffuse only shader -disabled bake and realtime GI -lowered resolution of game window - removed box collider from cube

-used MSI afterburner to measure D3D11 reported fps and frame times, confirms what profiler shows.

Looked around for the past few hours and am unable to find any information of the GPU Usage "other" that i'm seeing in the profiler. Unable to find anything useful

Spikes correspond to spikes in "GFX.WaitForPresent" on the CPU. From the forms apparantly all this means is that the cpu finished its work before the GPU and had to wait. Which while understandable, really doesn't mean anything. Still unable to figure out why it takes unity 5 up to ~20ms to render a simple cube with no reflections, shadows, scripts, physics, or textures.

I'm at a total loss.

http://imgur.com/bPy3cNm - picture of profiler