Cpu usage goes down with fps drops

[Psyche_Liquid]

So , I have been facing this problem in which I get massive fps drops and then fps goes back to what it was . I monitored my voltage and I realized whenever my fps drops come , the voltage goes down . I ran a prim95 test , it didnt show any errors and the cpu usage was always 100% and no voltage drops . But in games this happens . If someone has a fix please do tell me.

[TetraSky]

Specs?
Could be a case of throttling, either from overheating or from a GPU that doesn't match the performances of the CPU.