Banding with displayport

kernash · 09-07-2019, 03:51 AM

Hi,

When I connect my monitor with DisplayPort, I get banding around the 128-Value.
See the vertical step in the center of the screen:

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Same happens with all colors.
When using the DVI connector, this step disappears. How can I find out what is responsible for this?

Monitor: Eizo CS2410
GPU: IGP (i5-4690K/HD4600)
OS: Debian testing

kernash · 09-07-2019, 07:13 AM

I think I can answer the question myself (partially):

The difference between DP and DVI on the EDID output was that DP supports 10 bit color depth per channel.
After I set "DefaultDepth 30" in xorg.conf, the banding is almost gone. It is still somewhat visible, but far far less.

But apparently some programs seem to have problems with 30 bit color depth, for example chrome and chromium.
https://community.brave.com/t/wrong-...tforms/50266/5

Setting "DefaultDepth 24" is causing banding again.