(Solved) 2nd monitor is incorrectly recognized after a start up

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(Solved) 2nd monitor is incorrectly recognized after a start up

Post by David Chiang »

The manufacturer (LG) is recognized correctly, but 52" are assigned instead of 32". How can I change this without constant re-setting, so that the selected resolution remains permanently assigned? I think that once the monitor is recognized correctly, the settings should remain stable afterwards.
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Re: Second monitor is incorrectly recognized

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David Chiang wrote: Wed Jul 21, 2021 6:56 am The manufacturer (LG) is recognized correctly, but 52" are assigned instead of 32". How can I change this without constant re-setting, so that the selected resolution remains permanently assigned? I think that once the monitor is recognized correctly, the settings should remain stable afterwards.
Please post the output of inxi -Fxz from a terminal and enclose it in code tags [code]output.here[/code]. You'll see the code tags icon </> when you reply.
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Re: Second monitor is incorrectly recognized

Post by David Chiang »

The relevant section looks like this:

The second resolution is the wrong one!
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Re: Second monitor is incorrectly recognized

Post by Moonstone Man »

David Chiang wrote: Wed Jul 21, 2021 7:07 am The relevant section looks like this:
I specifically asked for the output of inxi -Fxz, not what you consider the "relevant section". Given that you can't solve the problem, you are not in a position to determine what I might consider to be relevant.
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Re: Second monitor is incorrectly recognized

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It is extremely unlikely that you will need all of the information it contains. If you need any further specific information, please let me know what exactly. By the way, you are in no position to ask anything of me that you actually don't need! :roll:
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Re: Second monitor is incorrectly recognized

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David Chiang wrote: Wed Jul 21, 2021 7:25 am It is extremely unlikely that you will ...
It's even more unlikely you'll get any more help.
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Re: Second monitor is incorrectly recognized

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Kadaitcha Man wrote: Wed Jul 21, 2021 7:28 am It's even more unlikely you'll get any more help.
That wasn't to be expected from you anyway! :lol:
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Re: Second monitor is incorrectly recognized

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David Chiang wrote: Wed Jul 21, 2021 7:25 am It is extremely unlikely that you will need all of the information it contains. If you need any further specific information, please let me know what exactly. By the way, you are in no position to ask anything of me that you actually don't need! :roll:
If you would have read Section 5 of READ: How To Get Help! you would know we need more than the one section you provided. That information does not include any personally identifying information so you just prolong your ability to get help when you do not provide what was asked.

Some people run into issues with LMDE because it uses an older kernel. That is relevant to your situation because AMD graphics drivers come from the kernel. To know if you might benefit from running a newer kernel through backports, we would need to see your hardware info and how Mint views that hardware info. That is why the full output of inxi -Fxxxrz is requested.
David Chiang wrote: Wed Jul 21, 2021 6:56 amI think that once the monitor is recognized correctly, the settings should remain stable afterwards.
And you saved the settings in the Display app after they were recognized correctly? By the way, those settings are saved in a Cinnamon file, but you didn't supply the requested inxi info so we do not know what version of Cinnamon you are using.

Please supply the info requested.
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Re: Second monitor is incorrectly recognized

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SMG wrote: Wed Jul 21, 2021 9:21 am Please supply the info requested.
Don't count on it. I expect that the avoidance is deliberate. Not that I place any weight whatsoever on signatures, but it does lead me to suspect that we may not be dealing with either LMDE or Linux Mint at all, and that the poster is under the misapprehension that we are stupid.
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Re: Second monitor is incorrectly recognized

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SMG wrote: Wed Jul 21, 2021 9:21 am If you would have read Section 5 of READ: "How To Get Help", you would know we need more than the one section you provided. That information does not include any personally identifying information ...
That's not true, the list contains several pieces of information that are not in the least related to the problem, such as the host name etc.
SMG wrote: Wed Jul 21, 2021 9:21 amSome people run into issues with LMDE because it uses an older kernel. That is relevant to your situation because AMD graphics drivers come from the kernel. To know if you might benefit from running a newer kernel through backports, we would need to see your hardware info and how Mint views that hardware info. That is why the full output of inxi -Fxxxrz is requested.
I don't think you need all the sections of the list to do this, although you need more than one.
SMG wrote: Wed Jul 21, 2021 9:21 amAnd you saved the settings in the Display app after they were recognized correctly?
Of course, how could I forget? I don't use the monitors at the same time, only individually, that means I switch one off and the other one on. Only the settings of the correctly recognized monitor are retained, those of the other one are automatically reset to the recommended value and that's not usable for me. An annoying side effect is also that the icons on the desktop are repeatedly deranged and then put back into order. By the way, the correctly recognized monitor is much newer than the other one from LG, so I find it quite unusual that the older device is not clearly recognized.

Wherever the cause may lie, I don't think the kernel is causing the problem!
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Re: Second monitor is incorrectly recognized

Post by AndyMH »

LG monitors can be troublesome, I've got one, what model and what is the native resolution?

With the monitor plugged in post the output from xrandr --verbose.

How is it connected, vga, DP, HDMI?
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Re: Second monitor is incorrectly recognized

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David Chiang wrote: Thu Jul 22, 2021 3:57 amThat's not true, the list contains several pieces of information that are not in the least related to the problem, such as the host name etc.
Host name does not show in the version of inxi I currently have, but when it did in past versions I just substituted my forum username. I've seen others put xxx for the host name.
David Chiang wrote: Thu Jul 22, 2021 3:57 amI don't use the monitors at the same time, only individually, that means I switch one off and the other one on.
There is a ~/.config/cinnamon-monitors.xml file which is supposed to retain saved information. Does it appear that file is being updated when you save in the Display app?

X Server re-polls the ports on the GPU periodically and if the monitor is turned off then it is removed from the server. When turned back on, the GPU sends what it detects. That is a factor of the GPU hardware and the graphics driver as well as the Mint code.

I am not able to tell from your description whether the identifier for the monitor is not correct and that may be why the wrong info is being used. There might be information in the Xorg log (/var/log/Xorg.0.log) which may give some clues as to how the monitor is being recognized. Unfortunately, not all monitors are correctly labeled by the manufacturer.
David Chiang wrote: Thu Jul 22, 2021 3:57 amWherever the cause may lie, I don't think the kernel is causing the problem!
Your computer's graphics drivers are loaded from the kernel. That is what the v. kernel means. If the graphics driver is the issue, then, in effect, the kernel is "causing" the problem.

Device-1: AMD Ellesmere [Radeon Pro WX 7100] driver: amdgpu v: kernel

That amdgpu driver does interact with your GPU and the ports on it which transmit the information to and from the monitor. That is one reason we ask what type of connection to your monitor you are using. Sometimes there are issues with the driver, but they only affect one type of port on the GPU. The specs I found for your GPU indicate it only had DisplayPorts.

TUF B450M-PRO GAMING: BIOS & FIRMWARE lists the latest version as 3202. I mention that because I see some of listed items affecting port and GPU issue. There is also an update for Ryzen 3000 Series Processors.

Machine:
Type: Desktop Mobo: ASUSTeK model: TUF B450M-PRO GAMING v: Rev X.0x
serial: <filter> UEFI: American Megatrends v: 2006 date: 11/13/2019
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Re: Second monitor is incorrectly recognized

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AndyMH wrote: Thu Jul 22, 2021 4:13 am LG monitors can be troublesome, I've got one, what model and what is the native resolution?
The Model is LG 32LH4900 and its maximum resolution for HDMI is 1920×1080 (HSync: 67.5 kHz, VSync: 60.0 Hz).
AndyMH wrote: Thu Jul 22, 2021 4:13 amWith the monitor plugged in post the output from xrandr --verbose.
Both monitors are permanently connected to the HTPC, they are only used alternatively, but never at the same time! The system can also distinguish between the main monitor and the secondary monitor depending on the respective setting. The sections for DP2 and DP3 are excluded here as they are not connected. It should also be mentioned that both devices are switched on at this point and the LG only shows the wallpaper, as it's not the "active" monitor at the moment. In addition, DP1 currently shows the last values I set that are normally to be used!
AndyMH wrote: Thu Jul 22, 2021 4:13 amHow is it connected, VGA, DP, HDMI?
The graphics card Radeon PRO WX 7100 has 4 DP connectors (DP0 - DP3).
The NEC MultiSync PA242W is directly connected from port DP0 to its DP-in connector and is always recognized without any problems,
the LG 32LH4900 is connected from port DP1 to a DP/HDMI adapter and from there to its HDMI-1 input, it doesn't have a DisplayPort input.
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Re: Second monitor is incorrectly recognized

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SMG wrote: Thu Jul 22, 2021 6:45 pm Host name does not show in the version of inxi I currently have, but when it did in past versions I just substituted my forum username. I've seen others put xxx for the host name.
I can only talk about my version and here is this information included which I had to cancel manually.
SMG wrote: Thu Jul 22, 2021 6:45 pmThere is a ~/.config/cinnamon-monitors.xml file which is supposed to retain saved information. Does it appear that file is being updated when you save in the Display app?
Yes it's always updated, last time was yesterday.
SMG wrote: Thu Jul 22, 2021 6:45 pmThere might be information in the Xorg log (/var/log/Xorg.0.log) which may give some clues as to how the monitor is being recognized. Unfortunately, not all monitors are correctly labeled by the manufacturer.
I have already thought about this, since the LG is a comparatively quite old device, it can not be ruled out that it does not identify itself completely. But since we don't really know that at the moment, it's too early for this diagnosis. :wink:
SMG wrote: Thu Jul 22, 2021 6:45 pm TUF B450M-PRO GAMING: BIOS & FIRMWARE lists the latest version as 3202. I mention that because I see some of listed items affecting port and GPU issue. There is also an update for Ryzen 3000 Series Processors.
I know that, but as long as there is no decisive reason, I will run my hardware as it is. I have already spent enough time in advance with almost endless research, just to make sure that all components are compatible with each other without restrictions, that should be enough for the time being. As far as I could tell, there have also been consumers who couldn't use a whole bunch of processors without an immediate BIOS upgrade. Fortunately, I am not affected by this! In addition, there is also a Linux driver from AMD for the graphics card, but despite its comprehensive functions it hasn't yet been installed, as it isn't yet needed. :lol:

One more word to the BIOS version: 2006 is from November 2019, so the version is new enough to recognise 99% of all devices from the last 20 years and as you can probably see, both of my monitors falls into this period. An update wouldn't change anything, because the problem exists with an older device and not with the very latest hardware as so often. Not to forget, my LMDE 4 system is still completely up-to-date (including the kernel), I hope that's enough for the moment!
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Re: Second monitor is incorrectly recognized

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Most people have complaints about monitor resolution because the native resolution is not showing. My understanding of what you have presented so far is that is not the case here. You have a personal preference you want for each monitor and Mint is only remembering to use that personal preference for the NEC MultiSync attached to DP-0. You are not using the native resolution (designated by the + preferred) for either monitor. You are using what is listed as * current.

Code: Select all

DisplayPort-0 connected primary 1280x800+0+0 (0x68) normal (normal left inverted right x axis y axis) 518mm x 324mm
  1920x1200 (0x5a) 154.000MHz -HSync +VSync +preferred
        h: width  1920 start 1968 end 2000 total 2080 skew    0 clock  74.04KHz
        v: height 1200 start 1203 end 1209 total 1235           clock  59.95Hz
  1280x800 (0x68) 154.000MHz -HSync +VSync *current
        h: width  1280 start 1968 end 2000 total 2080 skew    0 clock  74.04KHz
        v: height  800 start 1203 end 1209 total 1235           clock  59.95Hz
DisplayPort-1 connected 1360x768+1280+72 (0x81) normal (normal left inverted right x axis y axis) 1150mm x 650mm
  1920x1080 (0x78) 148.500MHz +HSync +VSync +preferred
        h: width  1920 start 2008 end 2052 total 2200 skew    0 clock  67.50KHz
        v: height 1080 start 1084 end 1089 total 1125           clock  60.00Hz
  1360x768 (0x81) 85.500MHz +HSync +VSync *current
        h: width  1360 start 1424 end 1536 total 1792 skew    0 clock  47.71KHz
        v: height  768 start  771 end  777 total  795           clock  60.02Hz
David Chiang wrote: Fri Jul 23, 2021 4:53 am The system can also distinguish between the main monitor and the secondary monitor depending on the respective setting.
For clarity, what "respective setting"? Does this just mean the correct resolution is showing when the NEC is in use?
David Chiang wrote: Fri Jul 23, 2021 6:14 amYes it's always updated, last time was yesterday, take a look:
I'm going to make an observation strictly based on what I see in the code (because I do not have much experience with this particular file).

You indicated, "Both monitors are permanently connected to the HTPC, they are only used alternatively, but never at the same time!" I would think that would mean there would be two configurations and each one would only have one monitor in them. That is not what I see. There is one configuration with just DP1 and another configuration with DP0 and DP1 and that second configuration has a different offset for x,y for DP1 as if both monitors are being used. To me, that would seem something other than what you wanted is what was saved?
David Chiang wrote: Fri Jul 23, 2021 6:14 amHere is an interesting excerpt from the log file, it even shows the serial number of the LG monitor (cancelled):
Which I take to mean that is the correct serial number, especially since the driver is picking up what appears to be the correct options for resolutions. (Sometimes different values show up in Xorg that do not show up in xrandr which is why I make that comment.)

It also indicates:

Code: Select all

[    21.673] (II) AMDGPU(0): First detailed timing is preferred mode
...
[    21.673] (II) AMDGPU(0): Supported detailed timing:
[    21.673] (II) AMDGPU(0): clock: 148.5 MHz   Image Size:  1150 x 650 mm
[    21.673] (II) AMDGPU(0): h_active: 1920  h_sync: 2008  h_sync_end 2052 h_blank_end 2200 h_border: 0
[    21.673] (II) AMDGPU(0): v_active: 1080  v_sync: 1084  v_sync_end 1089 v_blanking: 1125 v_border: 0
so it appears to be reading the monitor correctly.

And it does pick up your preferred resolution as an option.

Code: Select all

[    21.673] (II) AMDGPU(0): Monitor name: LG TV
...
[    21.673] (II) AMDGPU(0): h_active: 1360  h_sync: 1424  h_sync_end 1536 h_blank_end 1792 h_border: 0
[    21.673] (II) AMDGPU(0): v_active: 768  v_sync: 771  v_sync_end 777 v_blanking: 795 v_border: 0
David Chiang wrote: Fri Jul 23, 2021 6:14 amIn addition, there is also a Linux driver from AMD for the graphics card, but despite its comprehensive functions it hasn't yet been installed, as it isn't yet needed.
While there is a closed-source component to that driver archive, the bulk of the files are the same files are the same open-source files one can get from the kernel (depending upon which version of the kernel is used).

I was not able to find the specific driver which would work with your LMDE kernel, but the Release Notes for a newer version indicate a known issue "Display resolution resets to default for displays connected through multi display hub.". That is not the issue you are seeing, but it is an issue related to the GPU/driver regardless of the monitor. Such issues do exist which is why I mentioned that type of possibility.
David Chiang wrote: Fri Jul 23, 2021 6:14 amOne more word to the BIOS version: 2006 is from November 2019, so the version is new enough to recognise 99% of all devices from the last 20 years and as you can probably see, both of my monitors falls into this period. An update wouldn't change anything, because the problem exists with an older device and not with the very latest hardware as so often.
Your monitors are not connected to the mobo. I looked at the listed changes which indicate they would affect your GPU and your CPU which is why I let you know the updates are available. I only mention BIOS updates when I think they have applicability to the issue in the thread.

It appears to me that issues with the Display app are part of linuxmint / cinnamon-control-center because I found some issues posted related to the app.

In this older issue Display Module: Displays not detected? #241 I see a comment from the developer, "The new monitors.xml file (cinnamon-monitors.xml actually now) will only be created when you 'apply' changes. If you deleted your existing one, it's just autodetecting everything."

If you have two monitors and only one is ever used at a time, is the system seeing one as primary and the other as secondary or do they both show up as primary when they are in use? I wonder if that might be why both monitors are in the second configuration in the cinnamon-monitors.xml you posted.
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Re: Second monitor is incorrectly recognized

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SMG wrote: Fri Jul 23, 2021 4:17 pm For clarity, what "respective setting"? Does this just mean the correct resolution is showing when the NEC is in use?
The user has the possibility to determine which of his monitors is considered the main monitor and which is the secondary monitor. This setting is then also decisive for the further behaviour in the setup.
SMG wrote: Fri Jul 23, 2021 4:17 pmYou indicated, "Both monitors are permanently connected to the HTPC, they are only used alternatively, but never at the same time!" I would think that would mean there would be two configurations and each one would only have one monitor in them.
You have observed this correctly so far, this is also where part of the problem has arisen. :D
SMG wrote: Fri Jul 23, 2021 4:17 pmThere is one configuration with just DP1 and another configuration with DP0 and DP1 and that second configuration has a different offset for x,y for DP1 as if both monitors are being used. To me, that would seem something other than what you wanted is what was saved?
Correct, but why this could happen I will tell you below.
SMG wrote: Fri Jul 23, 2021 4:17 pmWhile there is a closed-source component to that driver archive, the bulk of the files are the same files are the same open-source files one can get from the kernel (depending upon which version of the kernel is used).
No, they are never the same, too many changes in the further development take place at AMD. Don't be misled here!
SMG wrote: Fri Jul 23, 2021 4:17 pmYour monitors are not connected to the mobo. I looked at the listed changes which indicate they would affect your GPU and your CPU which is why I let you know the updates are available. I only mention BIOS updates when I think they have applicability to the issue in the thread.
It no longer plays a major role where and how a component or device is connected to the hardware, the detection takes place via all bus systems, since most devices already communicate with each other. Moreover, with the best of intentions, I cannot imagine that someone without a reason will perform 5 BIOS upgrades in a period of 20 months just because they happen to be available. That would be an upgrade on average every 4 months and I don't know anyone who would update their BIOS just because of a vague suspicion. Forget it, you're totally wrong here!
SMG wrote: Fri Jul 23, 2021 4:17 pmIt appears to me that issues with the Display app are part of linuxmint / cinnamon-control-center because I found some issues posted related to the app.
This software is certainly underdeveloped and poorly documented, but definitely not the cause.
SMG wrote: Fri Jul 23, 2021 4:17 pmIn this older issue Display Module: Displays not detected? #241 I see a comment from the developer, "The new monitors.xml file (cinnamon-monitors.xml actually now) will only be created when you 'apply' changes. If you deleted your existing one, it's just autodetecting everything."
Ok, here you are on the right track, this is probably part of two causes that led to the problem.
SMG wrote: Fri Jul 23, 2021 4:17 pmIf you have two monitors and only one is ever used at a time, is the system seeing one as primary and the other as secondary or do they both show up as primary when they are in use? I wonder if that might be why both monitors are in the second configuration in the cinnamon-monitors.xml you posted.
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Re: 2nd monitor is incorrectly recognized when I start up with it

Post by David Chiang »

First of all, I would like to state what was demonstrably not the cause of the problem:
the BIOS, the graphics card and its generic driver software, the CPU, the GPU, the kernel, the operating system as a whole, the distribution and its update status, the hardware equipment of the HTPC, the topological arrangement of the respective devices, the type of connections and their underlying standards and a lot of things more.

And now let's get to the hard facts:
  1. For whatever reason, the LG monitor suppresses its type designation (32LH4900) in the EDID code, which means that the resolution recommended by the system is always the highest possible, because the monitor is not recognized well and therefore the wrong size (52" instead of 32") is assumed by the system. This fact was clear from the beginning and at the same time the cause for everything else.
  2. By considering only using one of the two monitors at a time, I let myself be carried away to configure them separately, which turned out to be an error that led to an unstable state in the configuration. This means that switching back and forth between the two monitors meant that the settings for the secondary monitor (LG) were lost each time and were reset by the system. Only after assigning the recognized NEC monitor as the main monitor and subsequently setting both resolutions from there, the situation has changed radically. It follows that it is absolutely necessary to first define the main monitor in order to then set both resolutions from there. Shouldn't this be possible from both monitors? Yes, with a high probability, but only if both monitors are recognized perfectly! At the same time, however, this is also an indicator that the configuration software is faulty, as it shouldn't actually allow any incorrect operation in this circumstances.
The main clues to solve my problem came from these two files: cinnamon-monitors.xml and Xorg.0.log, the latter clearly showing the core of the problem. By the way, thank you SMG for this hint, only then was it possible to circle the real causes. Everything else was unfortunately more or less useless, but this is just normal, as remote diagnosis is always difficult. :wink:
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Re: (Solved) 2nd monitor is incorrectly recognized when I start up with it

Post by AndyMH »

It sounds like you have fixed the problem. Can you state exactly what you did to solve it. This is for the benefit of others who may have the same problem.
You can also go back to your first post and edit it so you can added [solved] into the title.
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David Chiang
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Location: Higashiōsaka, Japan
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Re: (Solved) 2nd monitor is incorrectly recognized after a start up

Post by David Chiang »

After about a year and an upgrade to LMDE 5 Elsie plus the various updates for Cinnamon that followed, the following improvements and bug fixes have now emerged:
  1. The settings for two separately operated monitors are retained even if one of them was not correctly recognized.
  2. There is now a separate configuration file for each monitor, with each device being operated as a single device instead as one single and the other one as a double.
  3. Therefore, only one output is used on the graphics card at a time, exclusively DP0 or DP1 and no longer DP0 or DP0 + DP1 as before.
  4. The temperature of the graphics card remains at approx. 45°C in normal operation and at approx. 60°C for videos with 4K / 60 fps.
  5. At the same time, the arrangement of the icons on the desktop is now correct on both monitors, since the image formats set remain independent of one another.
Conclusion:
Even if the problem with the EDID device detection still exists, at least there are no more unpleasant side effects and the system is now much more consistent and stable than before. 8)
LMDE 5 Elsie (64-bit), Linux Kernel 5.10.0, Cinnamon 5.6.8, inxi 3.3.28;
HTPC: ASUS TUF B450M-Pro Gaming, 3.6 GHz AMD Ryzen 7 3700X (8 cores),
AMD Radeon Pro WX 7100, 2 × 4 TiB Seagate BarraCuda ES.3, 4 × 16 GiB HyperX Predator DDR4;
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SMG
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Location: USA

Re: (Solved) 2nd monitor is incorrectly recognized after a start up

Post by SMG »

David Chiang wrote: Wed Aug 10, 2022 6:18 am[*]There is now a separate configuration file for each monitor, with each device being operated as a single device instead as one single and the other one as a double.
What is the naming convention used for the files when there is more than one? Is it just a cinnamon-monitors1.xml and cinnamon-monitors2.xml type of situation?
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