Problems with two monitors

[Fernando]

Hi all.
I currently have two monitors: the primary one is a 2K screen with a resolution of 2560x1440 and is connected via HDMI while the secondary one has a resolution of 1440x900 and is connencted via DVI.

• The first problem is the global scale is set at 125% to make everything readable on the 2k screen, but this is too big for the secondary one so the question is: is there any way to set different scales for every monitor so I can set the secondary one to 100% while leaving the primary one as it is now at 125%?
• Second problem: with only my primary monitor connected (via HDMI) I can have sound through its built in speakers but if I connect the secondary one (via DVI), I loose the HDMI audio option. It appears in Pulse Audio Control (PAVU Control) as "not available (disconnected)". Both audio connections are on the video card. Can that have something to do?

Thanks in advance!

[jlittle]

(I have the same resolution monitors on my desktop at home. 2560x1440 is usually called QHD; 2K was originally 2048x1556 in cinema, then standardized as 2048x1080. I find my 27" QHD quite readable at my arm's length.)

Please tell us what graphics card, if any, the computer is using, and whether you are using X11 or Wayland. IIUC X11 only supports "global" scaling. If you're not using nVidia graphics, switching to Wayland might work.

DVI did not originally do audio. To use the audio on a monitor connected by DVI you had to connect it separately for audio, typically using audio cable. If your computer's DVI-D output does have audio you might need a DVI to HDMI cable to get sound to the monitor.

[Fernando]

Thanks for the quick reply, jlittle.

Please tell us what graphics card, if any, the computer is using

lspci | grep VGA

gives

01:00.0 VGA compatible controller: NVIDIA Corporation GF119 [GeForce GT 610] (rev a1)

I am using X11.

As for the driver,

sudo lshw -c video | grep 'configuration'

gives

configuration: depth=32 driver=nouveau latency=0 resolution=1920,1080

How can I try Wayland?

In relation to the audio problem, I think I didn't explain myself properly: I have perfect audio through HDMI on my primary monitor as long as I don't connect my secondary one. If i do, HDMI audio on my primary monitor is no longer available. I know I can't have audio through DVI on my secondary monitor (it also doesn't have built in speakers, so...).
Again, thanks.

[jlittle]

How can I try Wayland?

With Nvidia graphics, Wayland is supposed to have problems. I have no experience with this. One chooses a Wayland session from the the login screen. Wayland doesn't yet do, and may never do, some stuff I do with X11.

driver=nouveau

If you haven't already, you might try an Nvidia driver, if you can find one that supports the GeForce GT 610.

I have perfect audio through HDMI on my primary monitor as long as I don't connect my secondary one. If i do, HDMI audio on my primary monitor is no longer available.

Ah, I've no idea what's happening there. Perhaps an Nvidia person might have an idea.

[Fernando]

One chooses a Wayland session from the the login screen.

Login screen is not offering me that option. Am I missing something?

If you haven't already, you might try an Nvidia driver

I just went to System Settings and changed the driver to the offered proprietary driver from nVidia. I recovered the HDMI audio but I lost the 2560x1440 resolution that I had set through xrandr and now all I get is 1440x900 . If I try to run xrandr again to fix it, this happens

fer@lx-fer:~$ xrandr
Screen 0: minimum 8 x 8, current 3360 x 1170, maximum 16384 x 16384
DVI-I-0 disconnected (normal left inverted right x axis y axis)
VGA-0 disconnected (normal left inverted right x axis y axis)
DVI-I-1 connected 1440x900+0+270 (normal left inverted right x axis y axis) 410mm x 260mm
  1440x900      59.89 +  74.98*  
  1280x1024     75.02    60.02   
  1280x800      59.81   
  1152x864      75.00   
  1024x768      75.03    70.07    60.00   
  800x600       75.00    72.19    60.32    56.25   
  640x480       75.00    72.81    59.94   
HDMI-0 connected primary 1920x1080+1440+0 (normal left inverted right x axis y axis) 550mm x 310mm
  1920x1080     60.00*+  59.94    50.00    29.97    25.00    23.98    60.00    50.04   
  1680x1050     59.95   
  1600x900      60.00   
  1280x1024     75.02    60.02   
  1280x800      59.81   
  1280x720      60.00    59.94    50.00   
  1024x768      75.03    60.00   
  800x600       75.00    60.32   
  720x576       50.00   
  720x480       59.94   
  640x480       75.00    59.94    59.93   
 2560x1440_60.00 (0x2b7) 312.250MHz -HSync +VSync
       h: width  2560 start 2752 end 3024 total 3488 skew    0 clock  89.52KHz
       v: height 1440 start 1443 end 1448 total 1493           clock  59.96Hz
fer@lx-fer:~$ cvt 2560 1440 60
# 2560x1440 59.96 Hz (CVT 3.69M9) hsync: 89.52 kHz; pclk: 312.25 MHz
Modeline "2560x1440_60.00"  312.25  2560 2752 3024 3488  1440 1443 1448 1493 -hsync +vsync
fer@lx-fer:~$ sudo xrandr --newmode "2560x1440_60.00"  312.25  2560 2752 3024 3488  1440 1443 1448 1493 -hsync +vsync
X Error of failed request:  BadName (named color or font does not exist)
 Major opcode of failed request:  140 (RANDR)
 Minor opcode of failed request:  16 (RRCreateMode)
 Serial number of failed request:  31
 Current serial number in output stream:  31

So, apparently, the proprietary driver does support HDMI audio when two video outputs are connected, something that the nouveau driver seems not to but, at the same time, does not support 2560x1440 resolution...

[Fernando]

So, after much hassle, I got HDMI audio on the primary monitor back by changing the DVI connection of the secondary screen for a VGA cable and unplugging and plugging again the audio jack
The scaling problem remains unsolved.

[jlittle]

Wayland...
Login screen is not offering me that option. Am I missing something?

An Nvidia user may be able to advise on this. Ubuntu was going to make Wayland the default install in 22.04 but it was reported that Nvidia asked them not to.

Your experiences are typical of the reports we often see on KFN with Nvidia graphics. The conclusion that the closed source driver leads to problems is often made, but I can say no more.

I suspect that older Nvidia graphics will never support Wayland, so your scaling issue will have to wait for new hardware.

[claydoh]

To get get a Wayland session you need to install plasma-workspace-wayland to add the session option to your login.
Luckily, if one session is not working as desired, it is quick to log back in to the other session.