I afraid we can not just trust (EDID_version >= 1.4 && EDID_supports_10bit). Because this issue caused by any problematic component in the middle of pipeline. To ensure the compatibility, better to just defautly set bpc=8.
Think of one scenario, a speaker get his Ubuntu machine onto stage, plug the HDMI or DP projector which works well on latest speaker who is using Windows machine. Then, he get dark screen or audio function lost.... I guess the Ubuntu user might not aware it's caused by bpc. The default behavior should offer better user experience. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to mutter in Ubuntu. https://bugs.launchpad.net/bugs/1890772 Title: No signal on 4K 60Hz DisplayPort monitor by default, until "max bpc" is lowered to 8 Status in gnome-control-center: Unknown Status in Linux: Unknown Status in OEM Priority Project: New Status in X.Org X server: Unknown Status in linux package in Ubuntu: Confirmed Status in mutter package in Ubuntu: New Status in xorg-server package in Ubuntu: Triaged Bug description: The bug is originated from, https://bugs.launchpad.net/somerville/+bug/1887915/ https://bugs.launchpad.net/somerville/+bug/1886778 It has some problem when user connect to external 4K monitor with refresh rate 60. The problem can be solved by lower the bpc, or lower the refresh rate. `xrandr --output DP-3 --set "max bpc" 8` Would like to open this bug to open discussion for enhancing user experience. existed upstream bug: - https://gitlab.freedesktop.org/drm/intel/-/issues/1890 --- ProblemType: Bug ApportVersion: 2.20.11-0ubuntu27.4 Architecture: amd64 BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log' CasperMD5CheckResult: skip CompositorRunning: None CurrentDesktop: ubuntu:GNOME DistUpgraded: Fresh install DistributionChannelDescriptor: # This is the distribution channel descriptor for the OEM CDs # For more information see http://wiki.ubuntu.com/DistributionChannelDescriptor canonical-oem-somerville-focal-amd64-20200502-85+fossa-samwell-tgl+X42 DistroCodename: focal DistroRelease: Ubuntu 20.04 DistroVariant: ubuntu DkmsStatus: nvidia, 440.100, 5.6.0-1021-oem, x86_64: installed ExtraDebuggingInterest: Yes GraphicsCard: Intel Corporation Device [8086:9a49] (rev 01) (prog-if 00 [VGA controller]) Subsystem: Dell Device [1028:09fc] Subsystem: Dell GP107M [GeForce MX350] [1028:09fc] InstallationDate: Installed on 2020-08-07 (0 days ago) InstallationMedia: Ubuntu 20.04 "Focal" - Build amd64 LIVE Binary 20200502-05:58 Package: xorg 1:7.7+19ubuntu14 [origin: unknown] PackageArchitecture: amd64 ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.6.0-1021-oem root=UUID=41be2253-410a-4ef7-a096-4193a58efdbd ro quiet splash vt.handoff=7 ProcVersionSignature: Ubuntu 5.6.0-1021.21-oem 5.6.19 Tags: third-party-packages focal ubuntu Uname: Linux 5.6.0-1021-oem x86_64 UnreportableReason: This is not an official Ubuntu package. Please remove any third party package and try again. UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True version.compiz: compiz N/A version.libdrm2: libdrm2 2.4.101-2 version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.8-0ubuntu1~20.04.1 version.libgl1-mesa-glx: libgl1-mesa-glx N/A version.xserver-xorg-core: xserver-xorg-core 2:1.20.8-2ubuntu2.2 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-1 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20200226-1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1 To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1890772/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
