I've just done a new build as the old one was so bad that I'd be lucky to get above 20fps out in the open and going into Cherno or Electro was simply a bad mistake.
Anyway, what the new build has shown, as I can now run things pretty much maxed out with over 40fps everywhere on a full server (EU #5), is that I was getting a microstutter - it would hesitate and then carry on but it was regular. Had a look around and the first thing I did was install Game-Booster and this fixed it. For me it was a process running in the background.