Basic low resolution game stuttering

Why is my game stuttering even after changing scalability settings to medium for shadows and textures, it seems to drop 10fps at specific points.

I’m after smooth motion at 720p how can I configure my game so PIE runs at this res.

My game is running at 1680x1050 currently stats fps is showing a massive 120fps but it keeps dropping to 110fps intermittently, hence the annoying stutter.

My question is how can I configure this to get smooth gameplay regardless of fps at 720p without the stutter?

I’m running a 1080gtx, I’m surprised this is happening with such a basic game.