My aim is to run Witcher 3 at 80% or 90% of 4K, and with HDR. Special K gives me a black screen unless a) GOG overlay is disabled and b)the game is in borderless full screen at native res. If I run at fullscreen with SpecialK, I get a black screen. I made a custom resolution in Nvidia Control Panel for 90% of 4K, however if I select it even with borderless fullscreen then SpecialK again gives me a black screen/frozen screen.
This behaviour seems to be consistent regardless of whether HDR is enabled, and HDR works fine at native res and borderless fullscreen.
So any ideas of how I can get a custom resolution to work with specialK in this game? Thanks!
Also, out of curiosity, why does Window Resolution 3840x2160 at the top of SpecialK have a 250% next to it?