WhisperingWind You can set 8 bits with the command:
xrandr --output HDMI-1 --set "max bpc" 8
moonpie sudo cat /sys/kernel/debug/dri/1/i915_display_info
Run that command to find out if dithering is even on.
I thought I would migrate the latter discussion over here (out of the ditherig.exe topic). This is the MacBook Pro model with the "Intel Iris Pro 5200 Graphics " only. By default on Xubuntu, I get:
xubuntu@xubuntu:~$ sudo cat /sys/kernel/debug/dri/1/i915_display_info | grep -i dither
pipe src=2880x1800+0+0, dither=no, bpp=24
pipe src=0x0+0+0, dither=no, bpp=0
pipe src=0x0+0+0, dither=no, bpp=0
After xrandr --output eDP-1 --set "max bpc" 6, now I get:
xubuntu@xubuntu:~$ sudo cat /sys/kernel/debug/dri/1/i915_display_info | grep -i dither
pipe src=2880x1800+0+0, dither=yes, bpp=18
pipe src=0x0+0+0, dither=no, bpp=0
pipe src=0x0+0+0, dither=no, bpp=0
So maybe I wasn't crazy when I thought it felt worse after switching to 6-bit color. It seems bizarre to me that reducing the color depth would cause the driver to enable dithering. I must be missing some piece here.
Here are the full (original, 8bpc) details.