First, thank you very much , guys.
A lot of great advice here, it really helped me make my computer usable, and most of the headaches, or maybe all are gone.

My current setup:
OS:Windows 10 1903,
Ditherig.exe v1.13,
Graphic Card: Intel HD5500 Graphics,
Graphics Driver:Intel HD drivers, Version: 15.40.26.4474 , 2016, Intel says they're especially againt flicker[1].
Display:Benq GW2270, supposed to be flicker free. At 100% brightness. Browser brighteness is controlled via "Dark REader" chrome extension.

I'm currently testing my display using my phone camera and the notepad app fully opened. At a certain distance, i do see flicker lines.
Same results when graphics driver is disabled.

Is it possible, under windows, to fully solve that ? And for that , would i need to install windows 10 1507?

[1]https://downloadcenter.intel.com/download/27414/Beta-Intel-Graphics-Driver-for-Windows-10-and-Windows-7-8-1-15-40-?product=86210

It could help if you post a picture of the flicker. I doubt that Windows 1507 removes visible flicker though.

autobot That's just the moiré effect that happens when watching any pixel raster through a digital camera. Nothing to worry about.

    dev