Monitor detection problem

[Liamdale]

This is a new computer. It was originally delivered with Kubuntu 17.04 but I had to return it because of ssd failure. It was returned with Kubuntu 17.10

My problem: When I booted up Kubuntu 17.10, it failed to detect the correct monitor (LG 24MP48HQ) and gave me a standard unchangeable resolution of 1024x768. For a 24 inch monitor it is too low. I am using a HDMI connection.

In the Konsole I typed $ xrandr and got:

xrandr: Failed to get size of gamma for output default
Screen 0: minimum 1024 x 768, current 1024 x 768, maximum 1024 x 768
default connected primary 1024x768+0+0 0mm x 0mm
1024x768 76.00*

Can anyone identify the problem?

[GreyGeek]

There are no Linux drivers offered at http://www.lg.com/us/support-product/lg-24MP48HQ-P, and probably never will be, so being a new monitor some developer will have to create drivers for it and add them to ubuntu's repository.

Perhaps it is time to call the vendor and ask them to replace it with a display that works?

[oshunluvr]

This is an old problem that's been around for years - decades really. Most likely your monitor does not report it's EDID correctly or you have a bad cable.

Begin by reading your log file at /var/log/Xorg.0.log and see what it reports regarding monitor detection.

The solution will be to manually set the monitor so that xorg can configure it. These days, we no longer use xorg.conf and instead use separate section files in /etc/X11/xorg.conf.d/. I have two files there: 20-device.conf and 40-monitor.conf. Xorg reads them at boot time and applies your settings. You need to discover the correct specific settings for your monitor - scan freqs, resolution, DPI, etc. - and build a .conf file. Here's an example:

[COLOR=#000000][FONT=Verdana]Section "Monitor"[/FONT][/COLOR][COLOR=#000000][FONT=Verdana] 
    Identifier     "Monitor0" 
    VendorName     "LG"
    ModelName      "[/FONT][/COLOR][COLOR=#3E3E3E]24MP48HQ[/COLOR][COLOR=#000000][FONT=Verdana]"
    HorizSync       30.0 - 83.0
    VertRefresh     56.0 - 75.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce GTX 660"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "metamodes" "DVI-I-1: 1920x1080 +0+0, DFP-1: 1920x1080_60 +0+0, DFP-3: 1920x1080 +0+0"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection[/FONT][/COLOR]

You can also install the "read-edid" package and discover if, in fact, your EDID is readable and correct.

Another potential solution is to manually create xrandr commands that set you monitor properly after boot up, put I prefer to have the monitor correct during boot.

[Liamdale]

After my post I experimented with other connections. I connected my old computer (a pentium 4) using a vga cable (no HDMI) configured with Ubuntu 14.04 and the correct resolution was detected. I also rebooted my new computer with mint 18.2 (KDE) from a flash drive and again the correct resolution was displayed. Before my ssd drive died on this new computer, I had Kubuntu 17.04, the resolution was correct. The teck who installed the new ssd also installed Kubuntu 17.10. The problem seem to be the latest version of Kubuntu. One must expect upgrades to have problems.

I read the Xorg.0.log for both Kubuntu and Mint and have found differences. Both files could not identify the monitor:

Mint:

[ 14.246] (==) Log file: "/var/log/Xorg.0.log", Time: Thu Nov 9 14:52:22 2017
[ 14.247] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[ 14.247] (==) No Layout section. Using the first Screen section.
[ 14.247] (==) No screen section available. Using defaults.
[ 14.247] (**) |-->Screen "Default Screen Section" (0)
[ 14.247] (**) | |-->Monitor "<default monitor>"
[ 14.247] (==) No monitor specified for screen "Default Screen Section".
Using a default monitor configuration.

Kubuntu:

[ 3.574] (==) Log file: "/var/log/Xorg.0.log", Time: Thu Nov 9 09:30:26 2017
[ 3.575] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[ 3.575] (==) No Layout section. Using the first Screen section.
[ 3.575] (==) No screen section available. Using defaults.
[ 3.575] (**) |-->Screen "Default Screen Section" (0)
[ 3.575] (**) | |-->Monitor "<default monitor>"
[ 3.575] (==) No monitor specified for screen "Default Screen Section".
Using a default monitor configuration.

It is how the default was configured which is telling

mint 18.2

14.422] (II) intel(0): Creating default Display subsection in Screen section
"Default Screen Section" for depth/fbbpp 24/32
[ 14.422] (==) intel(0): Depth 24, (--) framebuffer bpp 32
[ 14.422] (==) intel(0): RGB weight 888
[ 14.422] (==) intel(0): Default visual is TrueColor
[ 14.423] (II) intel(0): Output DP1 has no monitor section
[ 14.423] (II) intel(0): Enabled output DP1
[ 14.423] (II) intel(0): Output HDMI1 has no monitor section
[ 14.423] (II) intel(0): Enabled output HDMI1
[ 14.423] (II) intel(0): Output HDMI2 has no monitor section
[ 14.423] (II) intel(0): Enabled output HDMI2
[ 14.423] (II) intel(0): Output HDMI3 has no monitor section
[ 14.423] (II) intel(0): Enabled output HDMI3
[ 14.423] (--) intel(0): Using a maximum size of 256x256 for hardware cursors
[ 14.423] (II) intel(0): Output VIRTUAL1 has no monitor section
[ 14.423] (II) intel(0): Enabled output VIRTUAL1
[ 14.423] (--) intel(0): Output HDMI2 using initial mode 1920x1080 on pipe 0
[ 14.423] (==) intel(0): TearFree disabled
[ 14.423] (==) intel(0): DPI set to (96, 96)

Kubuntu 17.10

[ 3.584] (II) FBDEV(0): Creating default Display subsection in Screen section
"Default Screen Section" for depth/fbbpp 24/32
[ 3.584] (==) FBDEV(0): Depth 24, (==) framebuffer bpp 32
[ 3.584] (==) FBDEV(0): RGB weight 888
[ 3.584] (==) FBDEV(0): Default visual is TrueColor
[ 3.584] (==) FBDEV(0): Using gamma correction (1.0, 1.0, 1.0)
[ 3.584] (II) FBDEV(0): hardware: EFI VGA (video memory: 3072kB)
[ 3.584] (II) FBDEV(0): checking modes against framebuffer device...
[ 3.584] (II) FBDEV(0): checking modes against monitor...
[ 3.584] (--) FBDEV(0): Virtual size is 1024x768 (pitch 1024)
[ 3.584] (**) FBDEV(0): Built-in mode "current": 78.7 MHz, 59.9 kHz, 75.7 Hz
[ 3.584] (II) FBDEV(0): Modeline "current"x0.0 78.65 1024 1056 1184 1312 768 772 776 792 -hsync -vsync -csync (59.9 kHz b)
[ 3.584] (==) FBDEV(0): DPI set to (96, 96)

The Kubuntu configuration does not seem to identify the HDMI connection.

My /etc/x11 folder does not have an xorg.conf.d/ folder. I asume that I must create it and add the 40-monitor.conf file.

Since this a completely new OS installation I am tempted to install my mint 18.2 to solve my problem but I will not learn how to solve a similar problem in the future.

Some questions on the code example:

You define three sections: Section "Monitor" , Section "Device" , Section "Screen". Does that mean I must have the 20-device.conf file in the /etc/x11/xorg.conf.d/ folder with a definition of my graphic device. I must mention that at this point I did not add a graphics card, I am using the on-board graphics of my Asus H270-pro motherboard.

I will also research read-edid package.

[oshunluvr]

You define three sections: Section "Monitor" , Section "Device" , Section "Screen". Does that mean I must have the 20-device.conf file in the /etc/x11/xorg.conf.d/ folder with a definition of my graphic device. I must mention that at this point I did not add a graphics card, I am using the on-board graphics of my Asus H270-pro motherboard.

Yes to the three sections. Built-in or plugged-in, you still have a graphics card.

[oshunluvr]

From that read out, your 17.10 install isn't using the Intel video driver.

[vinnywright]

From that read out, your 17.10 install isn't using the Intel video driver.

& that is what I was going to say ,,,it's on the frame buffer ,,,or vga

VINNY

[Liamdale]

I have difficulty understanding the coding before the narrative

ex: [ 3.584] (II) FBDEV(0): checking modes against monitor...

what is [3.584] and (II) and FBDEV(0)

Why would Kubuntu not use Intel driver. The specs show that the graphics are:
Integrated graphics processor - Intel HD Graphics support, Multi-VGA output support DP, HDMI, DVI-D

[Liamdale]

I installed and used read-edid:

$ sudo get-edid | parse-edid > edid.txt

This is read-edid version 3.0.2. Prepare for some fun.
Attempting to use i2c interface
Looks like no busses have an EDID. Sorry!
Attempting to use the classical VBE interface

Performing real mode VBE call
Interrupt 0x10 ax=0x4f00 bx=0x0 cx=0x0
Function supported
Call successful

VBE version 300
VBE string at 0xc92c0 "Intel(R) SKL/KBL Mobile/Desktop Graphics Chipset Accelerated VGA BIOS"

VBE/DDC service about to be called
Report DDC capabilities

Performing real mode VBE call
Interrupt 0x10 ax=0x4f15 bx=0x0 cx=0x0
Function supported
Call successful

Monitor and video card combination does not support DDC1 transfers
Monitor and video card combination supports DDC2 transfers
0 seconds per 128 byte EDID block transfer
Screen is not blanked during DDC transfer

Reading next EDID block

VBE/DDC service about to be called
Read EDID

Performing real mode VBE call
Interrupt 0x10 ax=0x4f15 bx=0x1 cx=0x0
Function supported
Call successful

EDID claims 1 more blocks left

*********** Something special has happened!
This happens a lot with TV's, and other devices
with extension blocks. If you have a TV, don't bother.
Odds are good that I2C will work for you. Try 'modprobe i2c-dev'.
Otherwise, please contact the author, Matthew Kern
E-mail: pyrophobicman@gmail.com
Please include full output from this program (especially that to stderr)

The monitor output is:

Section "Monitor"
Identifier "LG IPS FULLHD"
ModelName "LG IPS FULLHD"
VendorName "GSM"
# Monitor Manufactured week 1 of 2014
# EDID version 1.3
# Digital Display
DisplaySize 480 270
Gamma 2.20
Option "DPMS" "true"
Horizsync 30-83
VertRefresh 56-75
# Maximum pixel clock is 150MHz
#Not giving standard mode: 1152x864, 75Hz
#Not giving standard mode: 1280x1024, 60Hz
#Not giving standard mode: 1440x900, 60Hz
#Not giving standard mode: 1680x1050, 60Hz
#Not giving standard mode: 1600x900, 60Hz
#Not giving standard mode: 1280x800, 60Hz
#Not giving standard mode: 1280x720, 60Hz
#Not giving standard mode: 1400x1050, 60Hz

[GreyGeek]

I don't know what the "(II)" refers to but the "[3.584]" is the number of seconds since boot up started and FBDEV(0) referrers to the framebuffer video driver. Graphical displays use vector graphics, with the pixels between two verticies in an array, which represents the display, being turned on. The framebuffer driver scans the display pixels from left to right, top to bottom, turning on or off pixels. The FBDEV driver is usually a fallback video driver that delivers console text screens or ASCII graphics.

I believe oshunluver has you on the right path to display Nirvana.

[oshunluvr]

I don't know what the "(II)" refers to but the "[3.584]" is the number of seconds since boot up started and FBDEV(0) referrers to the framebuffer video driver. Graphical displays use vector graphics, with the pixels between to verticies in an arrary, which represents the display, being turned on. The framebuffer driver scans the display pixels from left to right, top to bottom, turning on or off pixels. The FBDEV driver is usually a fallback video driver that delivers console text screens or ASCII graphics.

The "(II)" in xorg log lingo means "Information", while "(WW)" means "Warning" and "(EE)" means "Error". Errors are usually fatal.

[GreyGeek]

An old dog learns a new trick!