Currently, the Nvidia G-sync activation algorithm does not trigger for any Window/Overlay that doesn’t hook into the game, while AMD and Intel’s VRR do.
Use any application that creates an unfocused Window. G Sync will be disabled for the game.
See an Example of “Lossless Scaling” Below:
LS creates a fullscreen, unfocused overlay window that covers the game window which remains in focus for receiving inputs. This directly disables the G Sync as soon as such window is activated.
Other Examples would be any other overlay that renders on top of the game as a Window.
Such as PresentMon, when not hooking into the game application it suffers from the same problem.
It creates a Window that resides on top of the game thus this will disable the G Sync for the game.
Unless you hook directly into the Game itself which is invasive as is, especially for Multiplier Tittles. There is no way for a developer to Activate G-sync on an unfocused window.
It would be amazing if we could raise some awareness on the issue and get Nvidia to fix this or give us the option to force G-Sync on for an unfocused window.