HELP Low FPS Low CPU/ GPU Usage.

[DonLyke]

Gonna keep this short. Up until today my laptop's been running fine. I tried playing PUBG today and the sound was very choppy and the game was very stuttery, fps was average 25 (I get 60+ usually). I've tried a lot of other games and it's the same thing. CPU and GPU aren't being used above 50%, and it isn't throttling because the temps max out at around 50 degrees. I've tried everything under the sun, last resort would be to factory restore the PC.
It's an MSI 6QF with an i7 6700hq and a 970m.

Any ideas guys? Help would be massively appreciated

 

[GhislainG]

Does your CPU run at 2.6 GHz when all cores are busy and up to 3.5 GHz when only one core is used? You need to check how fast the CPU runs; percentage isn't that significant with a 4 cores / 8 threads CPU. Monitor in Task Manager, Resources monitor or Intel XTU.