Thanks for the bug report. It appears your low resolution is due to the radeon kernel driver not being able to detect the monitor's EDID correctly:
[ 5.219380] radeon 0000:01:00.0: DP-1: EDID is invalid: [ 5.219384] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 5.219385] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 5.219386] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 5.219387] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 5.219387] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 5.219388] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 5.219389] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 5.219390] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 In case this was caused by a hardware change, please try a different DisplayPort cable or even a different monitor. Maybe even try just unplugging it at both ends and plugging it in again. If those don't fix the problem then the next step is to try some older kernel versions so as to try and find the last version in which the bug was not present. You can get all the kernel versions from here: https://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D ** Package changed: xorg (Ubuntu) => linux (Ubuntu) ** Summary changed: - Radeon issue + Radeon receives invalid EDID (all zeroes) ** Tags added: radeon ** Changed in: linux (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1829915 Title: Radeon receives invalid EDID (all zeroes) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1829915/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
