System Configuration:

Machine:	Intel Dual Xeon E5-2630
OS:	Xubuntu 18.10
GPU:	NVIDIA K4000
Monitors:	Dual Planar PX212M 1600x1200 Monitors

Problem Statement:       [Updated 01-23-19]

This system has been running fine for years under all past versions of Xubuntu up through 18.04. The dual monitors are configures without Xinerama so that separate desktop sessions with separate panels launch on each screen.

After the recent upgrade to Xubuntu 18.10, even though it is properly configured (see xorg.conf) the second monitor is not being recognized. (See display and arandr output below)

However, the second monitor is actually active:

• Upon boot it goes from black to a uniform grey


• The mouse can travel onto the second screen (pointer visible) and keyboard input (e.g., volume keys) are active


• Xscreensaver displays on both monitors when it goes active


• In a terminal window, issuing the command:   DISPLAY=:0.1 xfce4-terminal   displays the new terminal on the grey background of the second screen

I have tried to manually start an xfwm4 window manager, xfdesktop desktop and xfce4-panel panel on the second screen, with no success. See results below. I have also tried to create a $HOME/.xinitrc file with the desired command but this also fails.

In the following sections I have provided as much relevant information as possible. In particular, see the notes under the Log section.

So my questions are:

• What changed between Xubuntu 18.04 and 18.10 that is keeping the OS from detecting the second screen and configuring it properly and what can I do to rectify the problem?


• Supporting dual monitors with separate window managers seems like a common set-up, yet I can't find straightforward documentation on enabling this. Am I missing something?


• What modifications do I need to implement to get this second screen and desktop configuration re-enabled?

Thanks for any help you can offer.

NVIDIA Information:

The following driver package is in use.



Note: An earlier versions of the nvidia drive (v390) package was loaded, as well as trying the X.Org drivers, with no improvement.

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NVIDIA X Server Settings: /usr/bin/nvidia-settings



Note: Two screens are reported, likely due to the /etc/X11/xorg.conf settings. (See below.)

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NVIDIA X Server Settings: Display Configuration:



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NVIDIA X Server Settings: X Screen 0



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NVIDIA X Server Settings: X Screen 1



Note: Monitors and cables were swapped and Screen 1 was switched from GPU DP-2 to DP-3 port, all with no change.

X11 Settings:

Contents of /etc/X11/xorg.conf:

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings:  version 415.13

Section "ServerLayout"
	Identifier     "Layout0"
	Screen      0  "Screen0" 1600 0
	Screen      1  "Screen1" LeftOf "Screen0"
	InputDevice    "Keyboard0" "CoreKeyboard"
	InputDevice    "Mouse0" "CorePointer"
	Option         "Xinerama" "0"
EndSection

Section "Files"
EndSection

Section "InputDevice"
	# generated from default
	Identifier     "Mouse0"
	Driver         "mouse"
	Option         "Protocol" "auto"
	Option         "Device" "/dev/psaux"
	Option         "Emulate3Buttons" "no"
	Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
	# generated from default
	Identifier     "Keyboard0"
	Driver         "kbd"
EndSection

Section "Monitor"
	# HorizSync source: edid, VertRefresh source: edid
	Identifier     "Monitor0"
	VendorName     "Planar Systems, Inc."
	ModelName      "PX212M"
	HorizSync       31.0 - 92.0
	VertRefresh     56.0 - 86.0
	Option         "DPMS"
EndSection

Section "Monitor"
	# HorizSync source: edid, VertRefresh source: edid
	Identifier     "Monitor1"
	VendorName     "Planar Systems, Inc."
	ModelName      "PX212M"
	HorizSync       31.0 - 92.0
	VertRefresh     56.0 - 86.0
	Option         "DPMS"
EndSection

Section "Device"
	Identifier     "Device0"
	Driver         "nvidia"
	VendorName     "NVIDIA Corporation"
	BoardName      "Quadro K4000"
	BusID          "PCI:4:0:0"
	Screen          0
EndSection

Section "Device"
	Identifier     "Device1"
	Driver         "nvidia"
	VendorName     "NVIDIA Corporation"
	BoardName      "Quadro K4000"
	BusID          "PCI:4:0:0"
	Screen          1
EndSection

Section "Screen"
	Identifier     "Screen0"
	Device         "Device0"
	Monitor        "Monitor0"
	DefaultDepth    24
	Option         "Stereo" "0"
	Option         "nvidiaXineramaInfoOrder" "CRT-0"
	Option         "metamodes" "DVI-I-0: 1600x1200 +0+0"
	Option         "SLI" "Off"
	Option         "MultiGPU" "Off"
	Option         "BaseMosaic" "off"
	SubSection     "Display"
		Depth       24
	EndSubSection
EndSection

Section "Screen"
	Identifier     "Screen1"
	Device         "Device1"
	Monitor        "Monitor1"
	DefaultDepth    24
	Option         "nvidiaXineramaInfoOrder" "DFP-3"
	Option         "Stereo" "0"
	Option         "metamodes" "DP-3: 1600x1200 +0+0"
	Option         "SLI" "Off"
	Option         "MultiGPU" "Off"
	Option         "BaseMosaic" "off"
	SubSection     "Display"
		Depth       24
	EndSubSection
EndSection

Section "Extensions"
	Option         "(null)" "Disable"
EndSection
	

Display Configuration

Xfce Display Settings: xfce4-display-settings



Note: Only one screen found.

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ARandR Screen Layout: arandr



Note: Only one screen found.

Output From Various Commands:

Output from xrandr: xrandr

Screen 0: minimum 8 x 8, current 1600 x 1200, maximum 16384 x 16384
DVI-I-0 connected 1600x1200+0+0 (normal left inverted right x axis y axis) 432mm x 324mm
   1600x1200     60.00*+
   1280x1024     85.02    75.02    60.02
   1024x768      85.00    75.03    70.07    60.00
   800x600       85.06    75.00    72.19    60.32    56.25
   640x480       85.01    75.00    72.81    59.94
DVI-I-1 disconnected (normal left inverted right x axis y axis)
DP-0 disconnected (normal left inverted right x axis y axis)
DP-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
	

Note: No DP-3?   RandR must be numbering the display ports differently from NVIDIA.

The above output is identical to what you get with the command:   xrandr -display :0.0

However, you can probe the second screen with the command:   xrandr -display :0.1

Screen 1: minimum 8 x 8, current 1600 x 1200, maximum 16384 x 16384
DP-3 connected primary 1600x1200+0+0 (normal left inverted right x axis y axis) 432mm x 324mm
   1600x1200     60.00*+
   1280x1024     85.02    75.02    60.02  
   1024x768      85.00    75.03    70.07    60.00  
   800x600       85.06    75.00    72.19    60.32    56.25  
   640x480       85.01    75.00    72.81    59.94
	

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Output from lshw: lshw -c video

  *-display                 
       description: VGA compatible controller
       product: GK106GL [Quadro K4000]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:04:00.0
       version: a1
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress vga_controller bus_master cap_list rom
       configuration: driver=nvidia latency=0
       resources: irq:84 memory:b2000000-b2ffffff memory:a0000000-afffffff \
                  memory:b0000000-b1ffffff ioport:a000(size=128) memory:c0000-dffff
	

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Output from: xfce4-session --display=:0.1

Gtk-Message: 05:32:50.314: Failed to load module "atk-bridge"
xfce4-session: Another session manager is already running
	

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Output from: xfwm4 --display=:0.1

Gtk-Message: 05:35:08.701: Failed to load module "atk-bridge"
xfwm4-Message: 05:35:08.747: Another Window Manager (Xfwm4) is already running on screen :0.0
xfwm4-Message: 05:35:08.747: To replace the current window manager, try "--replace"
xfwm4-Message: 05:35:08.748: Another Window Manager (Xfwm4) is already running on screen :0.1
xfwm4-Message: 05:35:08.748: To replace the current window manager, try "--replace"

(xfwm4:5417): xfwm4-WARNING **: 05:35:08.748: Could not find a screen to manage, exiting
	

Note: you do not want to use the --replace option!

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Output from: xfdesktop --display=:0.1

Note: No output, but no desktop and still only one xfdesktop process.

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Output from: xfce4-panel --display=:0.1

(xfce4-panel:8085): xfce4-panel-CRITICAL **: 05:54:22.283: Name org.xfce.Panel lost on the message dbus, exiting.
	

Log Information:

A message from the log file: /var/log/Xorg.0.log

    [    46.177] (WW) NVIDIA(1): Unable to match display device name "DFP-3" from
    [    46.177] (WW) NVIDIA(1):    nvidiaXineramaInfoOrder
	

This is referring to the xorg.conf line:

    Option         "nvidiaXineramaInfoOrder" "DFP-3"
	

I don't see this as a problem as Xinerama is not being used. However, another section in the log file reports:

    [    36.494] (--) NVIDIA(0):     CRT-0 (boot)
    [    36.494] (--) NVIDIA(0):     DFP-0
    [    36.494] (--) NVIDIA(0):     DFP-1
    [    36.494] (--) NVIDIA(0):     DFP-2
    [    36.494] (--) NVIDIA(0):     DFP-3
    [    36.494] (--) NVIDIA(0):     DFP-4
    [    36.496] (II) NVIDIA(0): NVIDIA GPU Quadro K4000 (GK106GL) at PCI:4:0:0 (GPU-0)
    [    36.496] (--) NVIDIA(0): Memory: 3145728 kBytes
    [    36.496] (--) NVIDIA(0): VideoBIOS: 80.06.76.00.01
    [    36.496] (II) NVIDIA(0): Detected PCI Express Link width: 16X
    [    36.522] (--) NVIDIA(GPU-0): Planar Systems, Inc. PX212M (CRT-0): connected
    [    36.522] (--) NVIDIA(GPU-0): Planar Systems, Inc. PX212M (CRT-0): 400.0 MHz maximum pixel clock
    [    36.523] (--) NVIDIA(GPU-0):
    [    36.532] (--) NVIDIA(GPU-0): DFP-0: disconnected
    [    36.532] (--) NVIDIA(GPU-0): DFP-0: Internal TMDS
    [    36.532] (--) NVIDIA(GPU-0): DFP-0: 330.0 MHz maximum pixel clock
    [    36.532] (--) NVIDIA(GPU-0):
    [    36.532] (--) NVIDIA(GPU-0): DFP-1: disconnected
    [    36.532] (--) NVIDIA(GPU-0): DFP-1: Internal TMDS
    [    36.532] (--) NVIDIA(GPU-0): DFP-1: 165.0 MHz maximum pixel clock
    [    36.532] (--) NVIDIA(GPU-0):
    [    36.533] (--) NVIDIA(GPU-0): DFP-2: disconnected
    [    36.533] (--) NVIDIA(GPU-0): DFP-2: Internal TMDS
    [    36.533] (--) NVIDIA(GPU-0): DFP-2: 165.0 MHz maximum pixel clock
    [    36.533] (--) NVIDIA(GPU-0):
    [    36.533] (--) NVIDIA(GPU-0): DFP-3: disconnected
    [    36.533] (--) NVIDIA(GPU-0): DFP-3: Internal DisplayPort
    [    36.533] (--) NVIDIA(GPU-0): DFP-3: 960.0 MHz maximum pixel clock
    [    36.533] (--) NVIDIA(GPU-0): 
    [    36.534] (--) NVIDIA(GPU-0): Planar Systems, Inc. PX212M (DFP-4): connected
    [    36.534] (--) NVIDIA(GPU-0): Planar Systems, Inc. PX212M (DFP-4): Internal DisplayPort
    [    36.534] (--) NVIDIA(GPU-0): Planar Systems, Inc. PX212M (DFP-4): 960.0 MHz maximum pixel clock
	

So it seems that X11 sees and identifies the first monitor as CRT-0 (NVIDIA DVI-I-0), and the second monitor as DFP-4 (NVIDIA DP-3).

I edited the /etc/X11/xorg.conf file and changed DFP-3 to DFP-4 and rebooted. However, this didn't seem to improve anything other than to eliminate the warning message. The xfce4-display-settings and arandr utilities still only report a single screen.

Does anyone know the reason that Nvidia, xrandr and X11 all seem to be using different names for the various ports? I'd like to understand exactly what's going on here so that I could better cross-coordinate what these utilities are telling me.

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Link to NVIDIA log file: nvidia-bug-report.log.gz