Thanks for your work I just bought and tried a new 4K hdmi cable, with no change. I noticed that the monitor has TWO inputs, HDMI and HDMI/MHL (it had been plugged into HDMI) but switching this to HDMI/MHL gave no result.
I am using MATE but the same issue occurs in several flavours of Ubuntu that I have tried. I dont know how to try the new kernel at https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.8/ as you requested. If I attempt to ask Gdebi to load the linux-image-unsigned-5.8.0-050800-generic_5.8.0-050800.202008022230_amd64.deb package from https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.8/amd64/ it fails with unmet dependencies. kernel-modes.txt is attached ** Attachment added: "kernel-modes.txt" https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1890418/+attachment/5399129/+files/kernel-modes.txt -- 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/1890418 Title: i915 does not expose vendor-specific extended HDMI timings/modes To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1890418/+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
