Red Hat Bugzilla – Bug 1263788
Test case failure: Outputs - DP on ATI Pitcairn PRO [Radeon HD 7850] [1002:6819]
Last modified: 2015-09-23 10:34:19 EDT
Filed from caserun (https://tcms.engineering.redhat.com/run/260129/#caserun_10820272)
Version-Release number of selected component (if applicable):
Steps to Reproduce:
obtain a box with DP output and as much screens as can be attached
1. connect screens through DP port
2. perform suspend/resume cycle two times
If machine booted without DP, hotplugging will cause it to reboot immediately.
Otherwise (if booted with DP plugged in) DP works, but repeated hotpluging with 3+ monitors will cause it to stop working (xrandr will show DP monitor as working, but the monitor will go to sleep from lack of signal).
Screens should be correctly set, their native resolution should be set and
suspend/resume cycles should work as well
DP also suffers from mild temporary corruption on wake from standby - same as every digital output on this video card, this is a separate bug: https://bugzilla.redhat.com/show_bug.cgi?id=1263784
So talked with Vasiliy and we believe this was some electrical grounding issue on his test setup. We could not reproduce on mine.