[Hardware] Second Monitor can only mirror the primary Monitor

Graphical Environments, Managers, Multimedia & Desktop questions.
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[Hardware] Second Monitor can only mirror the primary Monitor

#1 Post by opiedopy »

I have posted little since I joined but I read a lot. My issue today is that I can not get my second monitor to be a dual display with different screen material. Instead it only mirrors the primary.
Sony Vaio 64 bit Laptop, running freshly installed Debian 11. Using lightdm as display manager.
My laptop display is primary. A LCD separate monitor is connected HDMI to HDMI should be secondary.
Both monitors show same screen.
Last year, when I first posted, I was new to Debian. Soon thereafter I decided to wipe the Debian and install Raspberry Pi Desktop Debian based, because I was so fond of it from using the Raspberry Pi 4. But because I now wanted to upgrade to Arduino 2.0, I decided to wipe Raspberry Pi Desktop (32 bit) and install Debian 11. All went well. But for almost a year I have enjoyed my dual monitors out of the box with R.Pi.Desktop, with dragging different screens left and right to have two different displays on the monitors. I want that feature back. And I know the Sony Vaio is capable of dual display hardware-wise. So it is my Debian installation or my display manager that are at issue? When plugging in the second monitor now I have no dual options in the display app on Debian.
I tried many things from the web to fix it but I have to admit I am really a software novice.
I have the following file dumps saved to text if they are helpful to anyone who may be able to provide me welcomed advice.
saved to text: inxi, lshw, lsmod, lspci, xor log

And the Debian 11 "display" app shows no option for undoing "mirror."

thanks in advance.

Screenshot from 2023-01-24 11-09-37.png

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Re: [Hardware] Second Monitor can only mirror the primary Monitor

#2 Post by donald »

When you connect the HDMI cable to the laptop what messages do you see in the log? Does the WM indicate a new output source is available?
Typo perfectionish.

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Re: [Hardware] Second Monitor can only mirror the primary Monitor

#3 Post by opiedopy »

My log was the result of this command:
:~$ cat /var/log/Xorg.0.log
The log was 2600 lines long, mostly lines about the many different screen resolutions.
I took a log without the secondary monitor plugged in, and one with the monitor plugged in
I then compared all lines.
The log without the secondary monitor plugged in had more lines than when the log was produced with the secondary monitor plugged in.
The lines between the ####'s were the same with and without the 2nd monitor.

debianisaac@debian11vaio:~$ cat /var/log/Xorg.0.log
X.Org X Server 1.20.11
X Protocol Version 11, Revision 0
[ 7.276] Build Operating System: linux Debian
[ 7.276] Current Operating System: Linux debian11vaio 5.10.0-21-amd64 #1 SMP Debian 5.10.162-1 (2023-01-21) x86_64
[ 7.276] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-5.10.0-21-amd64 root=UUID=f3b69dd7-98e8-438a-84b7-b71db5b31972 ro quiet
[ 7.276] (==) Log file: "/var/log/Xorg.0.log", Time: Tue Jan 24 15:07:20 2023
[ 7.293] (==) Using config directory: "/etc/X11/xorg.conf.d"
[ 7.293] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[ 7.302] (==) No Layout section. Using the first Screen section.
[ 7.302] (==) No screen section available. Using defaults.
[ 7.302] (**) |-->Screen "Default Screen Section" (0)
[ 7.302] (**) | |-->Monitor "<default monitor>"
[ 7.303] (==) No monitor specified for screen "Default Screen Section".
Using a default monitor configuration.

The following lines were in the log without the 2nd monitor but not in the log with the 2nd monitor.

[ 7.312] (==) ModulePath set to "/usr/lib/xorg/modules"
[ 7.312] (II) The server relies on udev to provide the list of input devices.
If no devices become available, reconfigure udev or disable AutoAddDevices.
[ 7.312] (II) Loader magic: 0x564785be6e40
[ 7.312] (II) Module ABI versions:
[ 7.312] X.Org ANSI C Emulation: 0.4
[ 7.313] X.Org Video Driver: 24.1
[ 7.313] X.Org XInput driver : 24.1
[ 7.313] X.Org Server Extension : 10.0
[ 7.313] (++) using VT number 7

[ 7.313] (II) systemd-logind: logind integration requires -keeptty and -keeptty was not provided, disabling logind integration
[ 7.331] (--) PCI:*(1@0:0:0) 1002:9591:104d:9035 rev 0, Mem @ 0xa0000000/536870912, 0xc0020000/65536, I/O @ 0x0000d000/256, BIOS @ 0x????????/131072
[ 7.338] (II) LoadModule: "glx"
[ 7.351] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so
[ 7.368] (II) Module glx: vendor="X.Org Foundation"
[ 7.368] compiled for 1.20.11, module version = 1.0.0
[ 7.368] ABI class: X.Org Server Extension, version 10.0
[ 7.368] (==) Matched ati as autoconfigured driver 0
[ 7.368] (==) Matched modesetting as autoconfigured driver 1
[ 7.368] (==) Matched fbdev as autoconfigured driver 2

You anticipated that the device plugged in would trigger a device available. But the opposite occured. The system gobbled up and accepted the 2nd monitor, but mirrored the display and gives me no option to have a separate info source displayed such as I had on the R Pi desktop and as I see on youtube examples of Debian. My system setup just seems to decide that a mirror is all I will get.

Here is an attachment of what I hope to be able to see with your or someone's help, two monitors....(note: picture is from the internet, not my system..)

Screenshot from 2023-01-24 22-08-23.png
Screenshot from 2023-01-24 22-08-23.png (54.94 KiB) Viewed 127 times
Last edited by opiedopy on 2023-01-25 03:22, edited 1 time in total.

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Re: [Hardware] Second Monitor can only mirror the primary Monitor

#4 Post by opiedopy »

and the command:
inxi -Fxz
produces the following exactly the same with and without 2nd monitor plugged in and workiing.

Kernel: 5.10.0-21-amd64 x86_64 bits: 64 compiler: gcc v: 10.2.1
Desktop: Cinnamon 4.8.6 Distro: Debian GNU/Linux 11 (bullseye)
Type: Laptop System: Sony product: VGN-FW390Y v: A222DJJM serial: <filter>
Mobo: Sony model: VAIO serial: <filter> BIOS: American Megatrends
v: R2050Y0 date: 11/07/2008
ID-1: BAT0 charge: 30.0 Wh condition: 40.9/50.6 Wh (81%) model: Sony Corp.
status: Charging
Info: Dual Core model: Intel Core2 Duo P8600 bits: 64 type: MCP
arch: Penryn rev: A L2 cache: 3 MiB
flags: lm nx pae sse sse2 sse3 sse4_1 ssse3 bogomips: 9574
Speed: 798 MHz min/max: 800/2401 MHz boost: enabled Core speeds (MHz):
1: 798 2: 798
Device-1: AMD RV635/M86 [Mobility Radeon HD 3650] vendor: Sony driver: N/A
bus ID: 01:00.0
Device-2: Ricoh Sony Vaio Integrated Webcam type: USB driver: uvcvideo
bus ID: 2-2:2
Display: x11 server: X.Org 1.20.11 driver: loaded: ati,vesa
unloaded: fbdev,modesetting,radeon resolution: 1152x864
OpenGL: renderer: llvmpipe (LLVM 11.0.1 128 bits) v: 4.5 Mesa 20.3.5
direct render: Yes

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Re: [Hardware] Second Monitor can only mirror the primary Monitor

#5 Post by fabien »

Code: Select all

xrandr --current
output might help diagnose

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Re: [Hardware] Second Monitor can only mirror the primary Monitor

#6 Post by dashek »

I recently needed to connect a projector to my laptop. I just wanted to set proper resolution/size on HDMI output, and just mirroring promary display was fine for me. I don't have any fancy gui settings app to set it up, so I went with using xrandr like this:

Code: Select all

xrandr --auto --output HDMI-1 --mode 1024x768 --auto --output eDP-1
I write about it here because this tool may help you. From xrandr(1) man page:
--left-of, --right-of, --above, --below, --same-as another-output
Use one of these options to position the output
relative to the position of another output. This
allows convenient tiling of outputs within the

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