On the left are buttons for resolutions 720, 1080, 2k, 4k, window and full screen. And There is a Quality up / down buttons with a number. 0 lowest. 4 highest.
Try 720, with 0 quality setting and see if that helps. You can set it 720 then full screen it I think for best performance. I added it last minute because they said One of the judges at lowerend system specs. So I hope it will help some people.