I'm signing in for this, too, I am also using ditherig.exe, and in my case (the screen is B156HAN01 v1.1) there is an easy way to detect when dithering is off, because banding appears. I have a Zbook 15 G3 and I have switched the display with one from Zbook 15, because of PWM. A am trying to attach 2 pictures to show the difference