Low GPU Usage on Low settings?

elfman5

Prominent
Nov 6, 2017
16
0
510
In Overwatch with Epic settings I get like 90-150 FPS, and my GPU usage is at 99% however when I switch over to low settings (for less input delay and my 180hz monitor) my GPU just sits at 30-50% my fps drops as low as 90 at times and it kinda sucks I cant maintain 180+ fps. Is this my cards problem? or is it designed to be this way , I've already tried using the "Prefer max performance" option in the nvidia control panel. any help would be appreciated thanks

PC specs
i5 7600k
GTX 1070 SC
16GB ram
 
so is it a CPU bottleneck?