3rd monitor can't display full-resolution with amdgpu and R9 380

[Will Rouesnel]

I have an AMD R9 380. This card under Windows displays full resolution (1920x1200x60) all 3 of my monitors perfectly. The connection setup is 2 x DVI, 1 Display Port with an active adaptor convered to DVI.

Using AMDGPU, the 3rd monitor is properly detected, it's resolution is detected and the card attempts to drive it, but the monitor cannot sync the display signal and flickers endlessly trying to do so.

Dropping the 3rd monitor resolution to 1650x1080x60 displays an image, but obviously not at full resolution.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: xorg (not installed)
ProcVersionSignature: Ubuntu 4.4.0-22.39-generic 4.4.8
Uname: Linux 4.4.0-22-generic x86_64
NonfreeKernelModules: zfs zunicode zcommon znvpair zavl
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CurrentDesktop: X-Cinnamon
Date: Sat May 14 15:51:03 2016
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)

[Paul White (paulw2u)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. We are sorry that we do not always have the capacity to review all reported bugs in a timely manner.

Ubuntu 16.04 (xenial) reached end-of-standard-support on April 29, 2021.

I'm setting the status of this bug to 'Incomplete' as it's not seen any activity for some time. If this is still an issue when using a currently maintained release of Ubuntu then please let us know which one(s) otherwise this bug report can be left to expire in approximately 60 days time.

[Launchpad Janitor (janitor)]

[Expired for xorg (Ubuntu) because there has been no activity for 60 days.]