I’ve been thinking about a hardware-level way to get around the scaling, dithering, and other “mystery processing” that GPUs and OS pipelines add to the signal before it hits the monitor
The idea:
Output a clean 1080p signal (no HiDPI, no OS scaling) from the computer
Feed that into a Retrotink 4K
Let it do a 4× integer upscale (nearest-neighbor) to 4K
The monitor then receives a native 4K signal with perfect pixel mapping, generated by the scaler rather than the GPU/OS
Because devices like the Retrotink reclock and regenerate the HDMI signal, they might also strip out some of the subtle timing/processing artifacts, the usual suspects (dithering, weird scaling filters, pixel shifting etc...)
For 1080p monitors: you could try 960×540 → 2× upscale
For 1440p monitors: you could test 720p → 2× upscale
The Retrotink 4K is pricey to import where I am, so I can’t test it easily.
This approach should work on macOS, Windows, Linux, anything with HDMI out
Some links
https://consolemods.org/wiki/AV:RetroTINK-4K/System_Specific_Settings
https://www.youtube.com/watch?v=Ix5Zd5_JZOc