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Monitor not recognised

asked 2015-10-23 03:45:49 -0500

updated 2016-03-25 05:08:36 -0500

hhlp gravatar image

Hello. I use Fedora 23 Gnome on a 64 bits PC, graphics: "Intel® Ivybridge Desktop", with a monitor Dell E2214HB, whose optimal resolution is 1920 x 1080 at 60 Hz:
http://www.dell.com/us/p/dell-e2214h/pd The monitor is connected by a VGA connector

Launching
journalctl -e _COMM=gdm-x-session
gives, among other lines:

(II) LoadModule: "vesa"
(II) Loading /usr/lib64/xorg/modules/drivers/ves
(II) Module vesa: vendor="X.Org Foundation"
(...)
(II) VESA: driver for VESA chipsets: vesa
(...)
(WW) Falling back to old probe method for vesa
(...)
(II) UnloadModule: "vesa"
(II) Unloading vesa

$ lsmod | grep video
video 36864 1 i915

$ xrandr
Screen 0: minimum 8 x 8, current 1024 x 768, maximum 32767 x 32767
DP1 disconnected (normal left inverted right x axis y axis)
HDMI1 disconnected (normal left inverted right x axis y axis)
VGA1 connected primary 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
1024x768 60.00*

800x600 60.32 56.25

848x480 60.00
640x480 59.94 VIRTUAL1 disconnected (normal left inverted right x axis y axis)

$ ls -l /etc/X11/
total 24
drwxr-xr-x. 2 root root 4096 Бич 10 17:23 applnk
drwxr-xr-x. 2 root root 4096 Тах 30 05:22 fontpath.d
drwxr-xr-x. 5 root root 4096 Нох 11 01:46 xinit
-rw-r--r--. 1 root root 547 Мог 19 14:16 Xmodmap
drwxr-xr-x. 2 root root 4096 Нох 16 18:10 xorg.conf.d
-rw-r--r--. 1 root root 493 Мог 19 14:16 Xresources

$ lspci
00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor DRAM Controller (rev 09)
00:02.0 VGA compatible controller: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor Graphics Controller (rev 09)
00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04)
00:1a.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 (rev 04)
00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 (rev b4)
00:1c.4 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 5 (rev b4)
00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 (rev 04)
00:1f.0 ISA bridge: Intel Corporation H61 Express Chipset Family LPC Controller (rev 04)
00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family SATA AHCI Controller (rev 04)
00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 04)
02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06)

My monitor seems not to be recognised and is treated as if it had a very low resolution. The problem appears in both Fedora 22 and Fedora 23 (fresh installation ... (more)

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Comments

You might consider giving more details about your system's specs, environment, etc.

ILMostro gravatar imageILMostro ( 2015-10-23 06:07:01 -0500 )edit

@ILMostro: thank you for your suggestion, but what information may be useful?

Fiable.biz gravatar imageFiable.biz ( 2015-10-25 23:00:10 -0500 )edit

Your video card brand and model.

aeperezt gravatar imageaeperezt ( 2015-10-26 11:46:15 -0500 )edit

@ILMostro

Could you post the output of

lsmod | grep video

xrandr (while the external display is attached)

ls -l /etc/X11/

lspci

deadrat gravatar imagedeadrat ( 2015-12-03 00:09:15 -0500 )edit

@ILMostro

Also mention how you have connected the displays. i.e., What cables / ports have you connected the displays to,

deadrat gravatar imagedeadrat ( 2015-12-03 00:17:59 -0500 )edit

2 Answers

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answered 2015-12-15 01:56:44 -0500

updated 2016-03-24 23:52:27 -0500

Workaround: First, i'm going to change the configuration temporarily, so that, if I make a mistake and get a blank screen, rebooting will restore the previous state. cvt outputs the mode for a desired resolution:

$ cvt 1920 1080
# 1920x1080 59.96 Hz (CVT 2.07M9) hsync: 67.16 kHz; pclk: 173.00 MHz
Modeline "1920x1080_60.00" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync

The part between quotations marks is the mode name. Then, I create this mode in xrandr, using its technical description i.e. the last line of the answer, except the word "Modeline":

$ xrandr --newmode "1920x1080_60.00" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync

No anwser: this is OK. Then I add this new mode to the connected output (if I have several connected output, I choose one) as stated by the answer of the command "xrandr" (with no argument), in my case: "VGA1":

$ xrandr --addmode VGA1 1920x1080_60.00

Eventually, I force the use of the said mode for that connected output:

$ xrandr --output VGA1 --mode 1920x1080_60.00

That's it. But how to make this change permanent?

Secondly, I make the change permanent: This solution is an adaptation of http://community.linuxmint.com/tutori... As root (superuser) I create a file called xorg.conf in /etc/X11 . Inside, I put the content below, finding the modline as above, the vendor name and model name from the back of my monitor (or from my bill or other paper document), the "Device" name "VGA1" from the command "xrandr" (See the question above.), and the "modes" are the beginning of the modeline. The "identifiers" are purely conventional, the important thing being that the "Monitor" field of the "Screen" section be equal to the "Identifier" field of the "Monitor" section.

Section "Monitor"
   Identifier "Monitor0"
   Modeline "1920x1080_60.00" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync
   VendorName "Dell"
   ModelName "E2214HB"
EndSection

Section "Screen"
   Identifier "Screen0"
   Device "VGA1"
   Monitor "Monitor0"
   SubSection "Display"
      Viewport 0 0
      Depth 1
      Modes "1920x1080"
   EndSubSection
   SubSection "Display"
      Viewport 0 0
      Depth 4
      Modes "1920x1080"
   EndSubSection
   SubSection "Display"
      Viewport 0 0
      Depth 8
      Modes "1920x1080"
   EndSubSection
   SubSection "Display"
      Viewport 0 0
      Depth 12
      Modes "1920x1080"
   EndSubSection
   SubSection "Display"
      Viewport 0 0
      Depth 16
      Modes "1920x1080"
   EndSubSection
   SubSection "Display"
      Viewport 0 0
      Depth 20
      Modes "1920x1080"
   EndSubSection
   SubSection "Display"
      Viewport 0 0
      Depth 24
      Modes "1920x1080"
   EndSubSection
EndSection
Then I rebooted and it works. But I have no idea of what are the "depths", and I guess there is probably a shorter way than repeating the "Display" subsection.

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Comments

You'd make it permanent with the correlating xorg.conf entries placed into a file in /etc/X11/org.conf.d/ . You don't need to run xrandr as root.

randomuser gravatar imagerandomuser ( 2015-12-15 08:30:48 -0500 )edit

Thank you. In /etc/X11/org.conf.d , I have only one file: 00-keyboard.conf , regarding the keyboard.

Fiable.biz gravatar imageFiable.biz ( 2015-12-16 00:16:24 -0500 )edit

Yes, you will need to create a new file there.

randomuser gravatar imagerandomuser ( 2015-12-16 07:49:57 -0500 )edit

OK, I corrected the answer and included the file into it. Could you check it please?

Fiable.biz gravatar imageFiable.biz ( 2016-01-08 03:53:01 -0500 )edit

Hi guys, I followed all steps, the workaround is working perfectly, but the permanent change is not working. I added the xorg.conf file but it seems it is not regognized.

the "Depth" line in xorg.conf is the color depth (16 means 16 bits, 24 means 24 its color depth) Do you any suggestions to make it work ? :)

I am using a Fedora 24, here are the working xrandr commands xrandr --newmode "2560x1440_60.00" 312.25 2560 2752 3024 3488 1440 1443 1448 1493 -hsync +vsync xrandr --addmode DisplayPort-0 2560x1440_60.00 xrandr --output DisplayPort-0 --mode 2560x1440_60.00

Thanks

Foxy gravatar imageFoxy ( 2016-10-26 04:40:05 -0500 )edit

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Asked: 2015-10-23 03:45:49 -0500

Seen: 2,592 times

Last updated: Mar 25 '16