Slight fps drop looks like a stutter

[MouseProblems11]

I've become very frustrated after getting a new PC because the problems of the old still affect me. Essentially, my PC constantly stutters in game. No matter what. It's noticeable when nothing but the game is open, but worse when watching youtube videos, and terrible when watching Netflix. 
I have a GTX 1080 ti, an i5 8600k, windows 10, and a 240hertz gsync monitor. 
When watching netflix, my game stutters every few seconds. I have my frame rate capped at 234 fps and it usually stays there but when it stutters it drops to 190. I moved my frame cap down to 90 but the game still stutters, but instead going down to 88 fps when it stutters. It only stays there for a second and the rises back to the capped fps but a few seconds later it goes down again and stutters. 
I disabled vsync, use high performance, checked that nothing is at 100% usage and nothing seems to fix it. I downloaded windows tweaker and that didn't fix it. 
I reinstalled nvidia drivers and no fix. 
The only thing that I can think of is that my version of windows is corrupted. These same issues plagued my old PC, and I just downloaded windows onto this PC using a USB flashdrive. 
Should I get another version of windows or try something else? 
Thank you because I don't know what else to do.