# Dithering
Some flat panels use only 6 bits per color channel, and are not able to display the 8-bit colors the video card outputs. But it is possible to simulate 8-bit colors with a 6-bit screen by turning on and off quickly the pixels. This process is known as dithering.
## Diagnose
If you can see stripes on this [[image|http://jonas-baehr.de/~mick/gradient.png]] , then you don't have 8 bit colors. 64 stripes means your driver, video card or monitor is only able to render 6-bit colors.
## Enable Dithering in Nouveau
### Select the right output
This command :
[[!format txt """
xrandr --prop
"""]]
will output something like that :
[[!format txt """
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
HDMI-1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 353mm x 198mm
EDID:
00ffffffffffff004ca34d3100000000
00120103802314780a87f594574f8c27
27505400000001010101010101010101
0101010101011d3680a070381e403020
250061c6100000190000000f00000000
00000000002091026400000000fe0053
414d53554e470a2020202020000000fe
00313630485430332d3030310a200060
dithering: Off
supported: Off On
scaling mode: Full
supported: None Full Center Full aspect
1920x1080 60.0*+ 60.0
1680x1050 60.0
1400x1050 60.0
1280x1024 59.9
1280x960 59.9
1152x864 60.0
1024x768 59.9
800x600 59.9
640x480 59.4
720x400 59.6
640x400 60.0
640x350 59.8
(null)-1 disconnected (normal left inverted right x axis y axis)
dithering: Off
supported: Off On
scaling mode: Full
supported: None Full Center Full aspect
VGA-1 disconnected (normal left inverted right x axis y axis)
scaling mode: None
supported: None Full Center Full aspect
"""]]
### Turn dithering on or off
We can see that dithering is off for HDMI-1, which seems to be the main monitor. Let's turn it on :
[[!format txt """
xrandr --output HDMI-1 --set dithering On
"""]]
If dithering was the cause of the color depth problem, then the stripes on the attached image should have disappeared.