I think you can't because DX12 doesn't has exclusive fullscreen at moment, the lack of that feature results in bordless fullscreen that use the V-Sync from your desktop, I don't know if there is a way to disable that.
So, for now you should use a backend that has exclusive fullscreen and turn off V-Sync.
So, for now you should use a backend that has exclusive fullscreen and turn off V-Sync.
CPU: Intel Core i7 3770 3.4 GHz (3.9 GHz with turbo boost) 4.23GHz with OC
RAM 12GB DDR3
[color=#009900]NVIDIA[/color] GTX 1070 [color=#000099]Asus[/color]
Windows [color=#3333ff]10[/color] Pro 64bit
Currently using Driver 452.06 [color=#00ff00]WHQL[/color]
RAM 12GB DDR3
[color=#009900]NVIDIA[/color] GTX 1070 [color=#000099]Asus[/color]
Windows [color=#3333ff]10[/color] Pro 64bit
Currently using Driver 452.06 [color=#00ff00]WHQL[/color]