CPU usage really low, causes low FPS in game

[Sarqo]

So I've just overclocked my CPU (Not much, by about 0.2GHz) to run a game at slightly more FPS, and it should have been enough to make a difference, but...
It's never even usage never even crosses 30 or 40%. I have the power options set to high performance, while my throttling stays at 0%.
Is there any way to maximise the cpu usage to get the most out of the game? The game, by the way, is PlanetSide 2, which is quite cpu-intensive. While I can get up to 160fps there, this drops to 50-80 in battles, and has quite long moments of 30fps or lower. I would like to minimise the amount of time these low fps moments occur for.
Spec:
Intel core i7 5820K Haswell-e Hexcore
2x MSI GTX 970 G4 Gaming in SLI
Asus X99-A Motherboard
Windows 7 Home Premium (in case the level of control matters)

 

[Fokissed]

Most games use 1-4 threads, and your processor supports 12, hence the low usage.

4 threads at 100% utilization will only look like 33% (4/12) in Task Manager.

Planetside 2 is notoriously processor bound, and a CPU OC will be the only way to increase FPS.

 

[Sarqo]

Thank you very much for the response But my cpu only goes up to 12%... Is that just because PS2 can't run quad-core?

 

[Fokissed]

Thank you very much for the response But my cpu only goes up to 12%... Is that just because PS2 can't run quad-core?

That's very likely. Most MMOs become processor bound on a few cores when there are lots of players in the vicinity.