SUMMARY On my PC, I have 2 screens: - one connected to DisplayPort (newly purchased), - one connected via HDMI. I have an AMD graphics card (newly purchased too). Putting the HDMI screen to sleep works, while the DisplayPort screen does not (the screen turns off and turns back on a few seconds later). Note that on the first attempt (after locking the session for example), the 2 screens turn off and turn on again after the configured delay, then on the 2nd attempt if I don't touch anything, only the screen in HDMI turns off for good, and the DisplayPort screen turns off and on again. I already had this problem with Plasma 5, it is still there with Plasma 6. STEPS TO REPRODUCE 1. Lock session 2. Wait for screen energy saving OBSERVED RESULT HDMI screen is turned off. DisplayPort screen is turned off and on. EXPECTED RESULT HDMI screen is turned off. DisplayPort screen is turned off. SOFTWARE/OS VERSIONS Operating System: Gentoo Linux 2.14 KDE Plasma Version: 6.0.1 KDE Frameworks Version: 6.0.0 Qt Version: 6.6.2 Kernel Version: 6.7.9-gentoo-x86_64 (64-bit) Graphics Platform: Wayland Processors: 8 × Intel® Core™ i7-9700K CPU @ 3.60GHz Memory: 31.3 Gio of RAM Graphics Processor: AMD Radeon RX 7800 XT ADDITIONAL INFORMATION If I don't connect to my Plasma wayland session, and I stay on SDDM, everything works! SDDM runs under X at the moment.
So basically, it works on X11, but not Wayland? Does it work in a full X11 session? Or only on SDDM which is running on X11?
I have just tested full X11 session on Plasma: the two screens turn off and turn back on immediately after locking followed by the configured time, then continue this cycle if I do nothing. I confirm that on SDDM with X11, without connecting to my session, everything works correctly. Should I try SDDM with Wayland? I'm not sure I'll get there quickly today.
So this is just about SDDM? Or while you are logged into your Plasma-6 session? Please note that the lockscreen is *not* SDDM. Since for me it works fine in Plasma 6 session with similar hardware (AMD RX 6700 attached to (a single) DisplayPort screen): KDE Plasma Version: 6.0.1 KDE Frameworks Version: 6.0.0 Qt Version: 6.6.2 Kernel Version: 6.6.21-gentoo (64-bit) Graphics Platform: Wayland
(In reply to Andreas Sturmlechner from comment #3) > So this is just about SDDM? Or while you are logged into your Plasma-6 > session? Please note that the lockscreen is *not* SDDM. Not at all, the issue is not about SDDM. And I know that the lockscreen is not at all SDDM, don't worry about that. ;) It is while I'm logged into my Plasma-6 session. I just tested what happen with SDDM, just to be sure it's not a general issue, because I know that SDDM is not lockscreen and vice-versa. :)
(In reply to Andreas Sturmlechner from comment #3) > Since for me it works fine in Plasma 6 session with similar hardware (AMD RX > 6700 attached to (a single) DisplayPort screen): Maybe I could try what happen if I plug only the DisplayPort Screen? And also, only the HDMI Screen? And then test in all situation I already reported (SDDM X11, Plasma-6 Wayland, Plasma-6 X11)? Would it help?
Interesting update. So far, here what I tested: - Plasma6 wayland, only HDMI screen plugged, when screen energy saving starts, it turns off and stay off! So it works if it is alone, - Plasma6 wayland, only DisplayPort screen plugged, when screen energy saving starts, it turns off and on. The bug. So we can say that when both screens are plugged, DisplayPort screen changes the behavior of HDMI screen… Also, another test came to my mind: what about a new user, with empty/default configuration of Plasma6? Well, I done this, and the bug is reproduced when both screen are plugged. Even worse, HDMI and DisplayPort screens turn off and on. (for recall, on my personal session only DisplayPort screen turns off and on, and HDMI is able to stay off, when it wants to) So we can say that it seems not linked to a specific configuration of my Plasma6 session. What do you want me to try next?
Another thing I found interesting. I was trying to change some settings of my DisplayPort Screen in Plasma6 configuration, just to test, or find something. Then I left open system settings, and after a manual lock, then wait for energy saving, then the bug… when I unlocked session, there was a message in system settings : « A new output has been added. Settings have been reloaded. » Maybe it is useful?
In any case, can you please upgrade to 6.0.2 to make sure this hasn't been fixed in the meantime.
(In reply to Andreas Sturmlechner from comment #8) > In any case, can you please upgrade to 6.0.2 to make sure this hasn't been > fixed in the meantime. Sorry, I forgot to mention it. I already upgraded to 6.0.2 today before this last test. Still same issue.
Created attachment 167187 [details] Energy Saving Settings I'm having the same issue, however this was working for me after updating to plasma 6, and only stopped working after I updated to 6.0.2 yesterday. I've tried multiple reboots, changing the power profile, still doesn't turn my displays off on the lock-screen (2 DP, 1 HDMI)
Another interesting thing: When I set "Turn off screen" to 1 minute (and keep lock screen to 5 minutes), and just wait 1 minute, then the issue is reproduced. So it seems that is not linked directly to lockscreen.
Setting to Confirmed since another user experienced the same result with 6.0.2
Upgraded to 6.0.4 some time ago, still the same issue.
Could this be a duplicate of Bug 480026? Which was fixed by ignoring display (re)connection events for 2 seconds instead of 1 after turning off the screens.
I applied the patches from https://invent.kde.org/plasma/kwin/-/merge_requests/5679. And the issue seems fixed with this! What I found weird, however: if I lock my screen, wait for 60 seconds the time before screens sleep, they try to do so, but fail, then in the next 60 seconds they succeed. It’s definitely better than before. ;)
*** This bug has been marked as a duplicate of bug 480026 ***