Bizarre Behaviour with External Monitor. Help please.

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Bizarre Behaviour with External Monitor. Help please.

Postby DoubtingT » May 2nd, '21, 05:43

Hi,

Acer Aspire 5750, Intel i5 2430M, Intel HD Graphics 3000.

Dual Boot with Windows 10.

Acer S276HL monitor used as external.

I updated from Mageia 7 to 8 with a clean install (using the external monitor as usual), with a self-burned DVD (checksums matched). It seemed to go well, but after the reboot, problems started. At the outset, the behaviour was unusual because the system immediately used as wallpaper a personal photo that I've been using for decades. Usually, I have to reapply this after a fresh install.

The wallpaper came up on my external monitor, but no Task Bar, Home Folder, Desktop Folder, or weather and clock widgets. On reboot (with splash screens and login behaving normally), I got no image at all on either laptop or external screen, but the external screen had a flashing line at the top. I suspected the system had loaded correctly but that the graphics had failed to resolve, so I used Ctrl f5 to get back to the laptop screen, where I discovered the system was indeed operational. I went into System Settings to set monitor behaviour; however, none of the settings stuck. Reboot always resolved wallpaper and nothing else. After some experimentation, I discovered that through Ctrl f5 I could unify outputs, which brought back the missing folders, widgets and Task Bar but with the external monitor at an incorrect resolution. I experimented more and discovered that Ctrl f5 - Unify - Switch to External Screen finally reset it to the correct resolution.

Here's the really weird thing: I wondered if the image itself might be causing the problem, so I deleted it in Desktop Settings - but it just came back at the next reboot.

Setting Folder View rather than Desktop View did open up the Desktop Folder, but still no Task Bar. At one stage, after I tried swapping between the two views, the desktop contents remained visible, with the Desktop View overlaying it.

Currently, the computer is booting into Folder View (with personal photo wallpaper) no matter what I specify, and the wastebin puts in an appearance (sometimes on the desktop, sometimes in the desktop folder) when it feels like it.

By now I'm a bit tired of this and I'm stumped about how to proceed. The monitor doesn't appear in the list of vendor-specific models in MCC - Setup Graphical Server; there doesn't seem to be any obvious way of getting the settings to lock between reboots; and just to pile on the agony, reboot hangs half the time at the monitor splash screen - but then again it's been doing this since installation of Mageia 7. Oh, and PyChess won't launch anymore.

Where could the personal photo be coming from? Is there some file or folder I can inspect to resolve the issue? I would appreciate any help anyone can offer.

Thanks for reading. Apologies for the length of the post.
DoubtingT
 
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Re: Bizarre Behaviour with External Monitor. Help please.

Postby doktor5000 » May 2nd, '21, 14:30

DoubtingT wrote:I updated from Mageia 7 to 8 with a clean install
Sorry but that doesn't make sense. Either you have a clean install, or an upgrade. Could you add some more details what you did in particular ?

Based on the other descriptions you added, seems you did an upgrade install from DVD or reinstalled but kept your existing /home filesystem. In any case, you still have your old KDE settings.
You would need to wipe some of the KDE settings, at least those from kscreen for the monitor configuration. Also check your X server configuration in /etc/X11/xorg.conf and in /etc/X11/xorg.conf.d/ - FWIW you should NOT select something specific for the external monitor, only select "Plug&Play".

For kscreen, move away/rename the following folders, then logout/login to KDE again and set your monitor configuration again
~/.kde4/share/apps/kscreen
~/.local/share/kscreen

Also post the output of
Code: Select all
xrandr -q
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Re: Bizarre Behaviour with External Monitor. Help please.

Postby DoubtingT » May 2nd, '21, 15:24

Hi,

Thanks for looking in.

I haven't gone through the kscreen amendments you suggest yet, but briefly, with regard to what I did during the upgrade, I thought retaining the home folder counted as a clean install. During the setup procedure, I took the 'use existing partitions' option, so I specified formatting of Root (??) folder only, which is set at 12 gb capacity. Prior to the install, it had shrunk to below 1gb spare (there have been many kernel updates over the course of 7's life). It's now back up to 6gb. The process deleted all of the additional programs I installed while using 7. I therefore had to reinstall Thunderbird for instance. I have gone through the same process many times without issue.

During setup, I did choose the PnP option for monitors. I only looked into a different option through MCC after the system acted up - but I didn't actually change anything.

It seems strange that pre-existing KDE settings should be problematical. I actually wanted to keep those settings, but one way or another they're not working the way they did in 7.

Actually, another strange thing is that Seamonkey was immediately available without my having to Edit applications from the task bar. Usually, I have to make the necessary amendment before it is usable (including dragging in the correct icon). On the other hand, my task bar link to Libre Office did *not* reappear.

I can't think of anything else that could be pertinent to the issue. I'll post the more specific information from xrandr as soon as I can.

Thanks again.
DoubtingT
 
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Re: Bizarre Behaviour with External Monitor. Help please.

Postby DoubtingT » May 2nd, '21, 18:25

I have looked at xorg.conf, but I don't know what to look out for, although there is already an 'old' version of it. xorg.conf.d seems to pertain to the keyboard.

I renamed the suggested KDE folders. In Local, a new Kscreen folder appeared. In Kde4, nothing has replaced the old folder so far.

I wondered if I should give the system a chance to PnP the monitor again, so I booted a couple of times with the external monitor disconnected. When I reconnected it, the personal photo appeared on the external screen (with no Taskbar etc.) at the same time as the Mageia standard wallpaper appeared on the laptop screen with Taskbar etc. in place.

When I tried replicating laptop screen to external, the photo transferred to the laptop screen, and Taskbar etc. disappeared on both. I could only get functionality back by cycling through Ctrl f5 options. Options I chose in System Settings disappeared on reboot.

I tried to adjust the placement of my Desktop folder, but it disappeared as soon as I clicked on it. The same thing happened to my weather widget.

On the plus side, reboot seems to be working properly now.

The weirdness seems very definitely associated with the way KDE is handling the external monitor. Is there some folder specific to it that I can adjust/delete?

Output from suggested code:

Code: Select all
$ xrandr -q
Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 32767 x 32767
LVDS1 connected (normal left inverted right x axis y axis)
   1366x768      60.00 +
   1280x720      60.00    59.74 
   1152x768      68.35 
   1024x768      74.81    60.00    60.00 
   1024x576      60.00    59.90    59.82 
   832x624       74.18 
   960x540       60.00    59.63    59.82 
   800x600       60.32    56.25 
   864x486       60.00    59.92    59.57 
   640x480       59.94 
DP1 disconnected (normal left inverted right x axis y axis)
HDMI1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 600mm x 340mm
   1920x1080     60.00*+  50.00    59.94 
   1680x1050     59.88 
   1280x1024     60.02 
   1440x900      59.90 
   1280x800      59.91 
   1152x864      75.00 
   1280x720      60.00    50.00    59.94 
   1024x768      70.07    60.00 
   800x600       60.32    56.25 
   720x576       50.00 
   720x480       60.00    59.94 
   640x480       66.67    60.00    59.95    59.94 
   720x400       70.08 
VGA1 disconnected (normal left inverted right x axis y axis)
VIRTUAL1 disconnected (normal left inverted right x axis y axis)
$


Update: I tried enabling laptop screen at the same time as external. Desktop folder and weather widget reappeared on the laptop screen - but with the personal photo background. It seems I have an unwanted extended workspace.

Thanks.
DoubtingT
 
Posts: 49
Joined: Jul 11th, '12, 15:21

Re: Bizarre Behaviour with External Monitor. Help please.

Postby doktor5000 » May 2nd, '21, 21:02

DoubtingT wrote:Is there some folder specific to it that I can adjust/delete?

The kscreen folders, as mentioned. Also see https://userbase.kde.org/System_Setting ... nd_Monitor - althougg the KDE documentation for this is a bit lacking/nonexistent.

You could also create a fresh user and see if the issue with the external monitor also persists for that user.

DoubtingT wrote:Update: I tried enabling laptop screen at the same time as external. Desktop folder and weather widget reappeared on the laptop screen - but with the personal photo background. It seems I have an unwanted extended workspace.

That can also be controlled via kscreen, you can just clone/mirror your displays in the meantime or for testing.
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Re: Bizarre Behaviour with External Monitor. Help please.

Postby DoubtingT » May 3rd, '21, 00:41

Okay, Google tells me that KDE has had problems handling dual monitors for years, so I suppose in a way the weirdest thing is that I've managed to bumble along without falling foul of them before.

I've found a YouTube tutorial on the subject from 2016. It proposes a fix through Xorg that bypasses the KDE controllers in System Settings, as these are basically unhelpful.

I'm going to try it out. If I have any success, I'll post back with a link to the tutorial.

Thanks for your help.
DoubtingT
 
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Re: Bizarre Behaviour with External Monitor. Help please.

Postby doktor5000 » May 3rd, '21, 16:36

DoubtingT wrote:It proposes a fix through Xorg that bypasses the KDE controllers in System Settings, as these are basically unhelpful.

That is usually the wrong way to go, as that way you always have to restart the X server to change any settings. I'd try to figure it out with xrandr or via the kscreen console what's happening, but it's your box ...
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Re: Bizarre Behaviour with External Monitor. Help please.

Postby DoubtingT » May 3rd, '21, 17:29

Okay. You've convinced me to scratch that idea. I actually have two dual-boot computers. As a temporary stopgap, I have now installed Gnome on one of them. It remembers monitor configuration but places the login on the laptop screen to begin with. That's good enough for other members of the household. I'll update to Mageia 8 KDE on the other one and do some more searching and tinkering. I'll post again if I come up with something.

As always, thank you for your help doktor5000.

Best regards.
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