Question: do i turn off vsync with gsync?
Answer: You want VSYNC set to OFF if you are going to be using GSync, period. There's no reason to use both at the same time. Also, G-Sync already FPS caps you at 144 FPS anyway, and your eyes won't see the difference between 144 FPS and 200 FPS because your monitor can't refresh that fast anyway. Not entirely correct.