Low GPU usage but not hitting high frames

[connorcam123]

When playing games my FPS will almost never hit 144 FPS on Dota 2 I hit 120 FPS max and on Overwatch around 110 max. However my GPU usage always stays at around 40% is there a bottleneck and if so where? My parts are as follows,

CPU: Intel Core i7 4790K (Overclocked 4.8 GHz)
GPU: Nvidia GTX 1070 TI (Memory Clock upped to 4482 MHz)
Motherboard: Gigabyte Z97X-SLI-CF
SSD: SanDisk Ultra II 480GB
HDD: Seagate 1TB

 

[TechyInAZ]

Make sure V sync and/or G sync is disabled.

I'm not sure about both of those games, but there is a possibility that the game itself has a frame limiter built in, for example in Titanfall 2 there is an in game limit of 144fps and Portal 2/CSGO has an in game FPS limit of 300 (which you can change in the console).