Thanks that does seem to be an old EDID v1.3 with no defined bit depth. But there are some vendor-specific blocks there that do advertise support for 10bpc and 12bpc.
In this case I think it's correct to try and default to 10bpc or 12bpc. It's probably only the cable or dongle letting it down. I wonder if such limited cable bandwidth is something we can detect in software?... Imagine (or please test) what a newer monitor with an EDID v1.4 would do. If that reported more definite support for 10bpc then it would be even more correct to try and default to 10bpc. But we would also need more intelligent logic (somewhere) that detects when the desired bandwidth isn't being achieved due to cable or dongle problems. ** Changed in: xorg-server (Ubuntu) Importance: Undecided => Medium ** Changed in: xorg-server (Ubuntu) Status: Incomplete => Triaged ** Changed in: oem-priority Status: Incomplete => New ** Also affects: linux (Ubuntu) Importance: Undecided Status: New ** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Also affects: mutter (Ubuntu) Importance: Undecided Status: New ** Changed in: mutter (Ubuntu) Importance: Undecided => Medium -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1890772 Title: Some external 4K monitor is not working properly To manage notifications about this bug go to: https://bugs.launchpad.net/oem-priority/+bug/1890772/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp