Tuesday, June 4th 2019
Microsoft Extends Variable Refresh Rate to Games that Lack Native Support
Microsoft extended variable refresh-rate (VRR) to games that don't natively support it, through a new global setting under Graphics Settings. To access this setting, you must have the latest Windows 10 May 2019 Update (version 1903), a display that supports NVIDIA G-Sync, AMD FreeSync, or VESA Adaptive-Sync, and a graphics processor with a WDDM 2.6-compliant driver that supports these VRR technologies. For now, this setting only works with DirectX 11 games in exclusive-fullscreen mode. Microsoft clarified that this setting is not designed to override the VRR options presented by the control panels of your display driver provider (eg: NVIDIA Control Panel or AMD Radeon Settings). The option is disabled by default, and isn't visible to users who don't meet both the hardware- and software-requirements of VRR.
Source:
Microsoft DevBlogs
9 Comments on Microsoft Extends Variable Refresh Rate to Games that Lack Native Support
This is frame based, not game based.
forums.geforce.com/default/topic/1118895/geforce-drivers/windows-10-1903-variable-refresh-rate-system-option-is-missing/
I think this setting is specifically for games that are on Microsoft's store that comes with disabled vrr on them. Probably when you start it , it overrides your system to disable vrr, it doesn't make any sense but that is the only explanation. Games can disable vrr if active or vice versa but for that vrr needs to be global active.