You want it turned off
V-sync connects your video card and monitor and forces the video card to stay at the monitors setting no matter what u change
Off would be best especially since you got a 780 so an upper end card
Also theres a setting in game and sometimes the graphics control panels may have one as well but I'd start in game, if you can't turn vsync off in game again if you look into the editing of the INI files, usually vsync is a setting in the same file as fps since they're related to one another
But again you'd wanna look into this for the games themselves as you don't want the game to label you as a cheater for no reason
Also forgot this earlier editing INI files can cause the game to no longer run so if you find that that's a route you wish to take plz take the time to research it a bit will save a lot of headaches later on
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