Question Frequent stuttering in no particular order

[dobboman]

My PC has been on and off stuttering for a while now.
I have tried re-seating my GPU, RAM, and tried another power supply.
I cannot figure out what is causing it, however, there is a buzzing sound inside the computer, and when it stops, is when the stutters occur. Still unable to find where the buzzing sound is from. When plugging in my power supply cable in to my power supply, I hear electricity, not sure if that helps.
SPECS:
CPU i5 8400
GPU GTX 1060 6GB OC
MOBO H310M Pro VH
RAM 2x8 GB DDR4 2400MHZ RAM
Any details required don't hesitate to ask! Thanks so much.

 

[dobboman]

To add on, I have noticed that my cpu drops to around 80% usage in the stutters when usually on 100% during gaming.