Terrible CPU usage from i7-5820k

[Supertoaster77]

I get terrible CPU usage in games. For example, Fallout 4 which was touted to be very resource greedy, never goes above 25% CPU usage. I've tweaked the hyperthread setting in the ini file but it does nothing. I get shit framerates because of this.
Asus X99-A mobo
i7-5820k @ 3.3 GHz (12 cpus)
Nvidia Geforce GTX 980 ti
16 gigabyte DDR4 RAM at ~2133 MHz
Windows 10
Monitor refresh rate is 60 hertz

 

[Supertoaster77]

I get a CPU mark score of 12666 and all temps check out under load.