External monitor not detected on Ubuntu 18.04

Question

After upgrading to Ubuntu 18.04, my laptop has been unable to detect/use an external monitor attached via HDMI. Even when plugged in, the "detect displays" button within the default settings app doesn't do anything.

Here is the output from xrandr:

Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 16384 x 16384
eDP-1-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
   1920x1080     60.01*+  60.01    59.97    59.96    59.93  
   1680x1050     59.95    59.88  
   1600x1024     60.17  
   1400x1050     59.98  
   1600x900      59.99    59.94    59.95    59.82  
   1280x1024     60.02  
   1440x900      59.89  
   1400x900      59.96    59.88  
   1280x960      60.00  
   1440x810      60.00    59.97  
   1368x768      59.88    59.85  
   1360x768      59.80    59.96  
   1280x800      59.99    59.97    59.81    59.91  
   1152x864      60.00  
   1280x720      60.00    59.99    59.86    59.74  
   1024x768      60.04    60.00  
   960x720       60.00  
   928x696       60.05  
   896x672       60.01  
   1024x576      59.95    59.96    59.90    59.82  
   960x600       59.93    60.00  
   960x540       59.96    59.99    59.63    59.82  
   800x600       60.00    60.32    56.25  
   840x525       60.01    59.88  
   864x486       59.92    59.57  
   800x512       60.17  
   700x525       59.98  
   800x450       59.95    59.82  
   640x512       60.02  
   720x450       59.89  
   700x450       59.96    59.88  
   640x480       60.00    59.94  
   720x405       59.51    58.99  
   684x384       59.88    59.85  
   680x384       59.80    59.96  
   640x400       59.88    59.98  
   576x432       60.06  
   640x360       59.86    59.83    59.84    59.32  
   512x384       60.00  
   512x288       60.00    59.92  
   480x270       59.63    59.82  
   400x300       60.32    56.34  
   432x243       59.92    59.57  
   320x240       60.05  
   360x202       59.51    59.13  
   320x180       59.84    59.32  
DP-1-1 disconnected (normal left inverted right x axis y axis)
HDMI-1-1 disconnected (normal left inverted right x axis y axis)

My main concern is the final line: HDMI-1-1 disconnected. There is a monitor plugged in and ready for use, and nothing I do seems to cause it to be detected.

I have an nvidia graphics card, and before the update I was using proprietary drivers. When the external display problem first arose, my initial attempt was to switch back to the open source Xorg drivers. However, upon reboot, Ubuntu displayed my driver settings as using a "manually installed driver", and won't let me change it:

Any recommendations?

What do you call open source Xorg driver ? is it the nouveau driver ? — solsTiCe, May 08 '18 at 22:07
This problem seemingly fixed itself. For any future readers experiencing the same issue: I launched an i3 session (as opposed to gnome) and then rebooted and the problem was solved. I don't expect that the two things are correlated, but if you're really stuck, it could be worth a shot. — PullJosh, May 08 '18 at 23:27
For me, no "detect displays" button in displays settings. :( — angelcervera, May 13 '18 at 10:32
@PullJosh Do you want to answer your own question or delete it? If you answer it and accept it, new answers that are way off base can be avoided. Thanks. — WinEunuuchs2Unix, Jun 15 '18 at 22:33
@angelcervera's answer solved it for me. For reference, here are two very detailed threads outlining some other potential solutions: https://devtalk.nvidia.com/default/topic/1035768/linux/ubuntu-18-04-can-t-see-second-monitor/, https://devtalk.nvidia.com/default/topic/1032482/optimus-on-ubuntu-18-04-is-a-step-backwards-but-i-found-the-first-good-solution/ — dskrvk, Sep 13 '18 at 01:36
@dskrvk Great links. Could I add both in my answer? Of course, adding you in the credits. :) — angelcervera, Sep 13 '18 at 15:11
PSA: Check to see if it's plugged in first. The alpha of all IT problems. — Brandon Bertelsen, Feb 07 '20 at 15:28
Tried everything here - nothing worked for me. Finally found this https://forums.linuxmint.com/viewtopic.php?f=59&t=154932&start=20#p847465 and installed latest driver from .run file. — Myshko, Mar 30 '20 at 07:34
My Dell laptop wouldn't see a USB Type-C (Thunderbolt) external monitor. I solved the problem by tweaking Thunderbolt settings in BIOS — Anton3, Feb 01 '21 at 08:49
Also, sudo apt-get install laptop-mode-tools && sudo lmt-config-gui and enabling video-out might help — Anton3, Feb 04 '21 at 09:18

score 81 · Answer 1 · answered Dec 10 '18 at 09:22

81

I solved it by purging, then reinstalling the nvidia drivers

sudo apt-get purge 'nvidia*'
sudo add-apt-repository ppa:graphics-drivers
sudo apt-get update

Then using the Software & Updates tool's Additional Drivers tab and installing the latest nvidia drivers

answered Dec 10 '18 at 09:22

Attila Szeremi

918
6
5

25

I did this followed by sudo ubuntu-drivers autoinstall as recommended by @Kasuyakema and it worked. – jaycode Jan 20 '20 at 13:25
2

Got some strange responses from the shell on following these steps, but worked in the end after a reboot. – ijuneja Mar 22 '20 at 06:34
This together wither @jaycode command an a reboot solved it for me with USB-C connected display. – Tschallacka Jun 10 '21 at 08:11
4

I tried this with Ubuntu 20.04 and 5.11.0-37-generic kernel, which installed NVIDIA driver 470 ... and got locked out of my laptop :( Black screen of death. Had to drop to root login shell in recovery switch drivers and changed back to nouveau driver. NVIDIA is HORRIBLE with respect to driver support for Linux. – Yash Jakhotiya Oct 17 '21 at 19:20
1

I tried above step and then did sudo ubuntu-drivers autoinstall , after reboot it went fine. – Mahadev Gouda Jul 04 '22 at 04:07

score 44 · Answer 2 · edited Apr 14 '22 at 03:58

44

Solved for me by updating to recommended Nvidia card drivers how-to.

To install all recommended drivers:

sudo ubuntu-drivers autoinstall

edited Apr 14 '22 at 03:58

vvvvv

608

answered Sep 11 '18 at 17:00

Kasuyakema

549

1

Yep, this solved my issue as well. I tried to connect my DELL Inspiron G3 i7 32GB 480+1TB GTXTi to LED IIYAMA 28" with Ubuntu 18.04 LTS. – wawka Mar 10 '19 at 09:40
I did
```
sudo apt-get purge 'nvidia*'
sudo add-apt-repository ppa:graphics-drivers
sudo apt-get update
```
as recommended by @Attila Szeremi followed by this and it worked.
– jaycode Jan 20 '20 at 13:26
This one scre**d up my linux mint, impossible to restart untill I did like @Attila Szeremi mentionned – TOPKAT Jan 27 '20 at 11:36
Oops, I held broken packages (Ubuntu 20.04.3) and it failed. I have to use Attila Szeremi's method by installing Nvidia packages myself. – Teddy van Jerry Feb 21 '22 at 05:03
This solution worked with Ubuntu MATE 20.04. With Nvidia Performance mode. – PoundXI Apr 22 '22 at 08:54
2

This did it for me. Quite simple and elegant. Running on Ubuntu 22.04 LTS. Thanks! – RawCode May 21 '22 at 08:20
confirming this solution for Ubuntu 22.04.2 LTS w/ KDE Plasma, June 2023. Don't forget to reboot :) – skytwosea Jun 24 '23 at 21:29

score 31 · Answer 3 · edited Aug 29 '18 at 17:47

31

I solved the problem installing lightdm and set it as the default display manager.

In the process, something changes because is starting to detect external displays again even if you go back to GDM3.

You can follow the instructions here on how to make these changes:

sudo dpkg-reconfigure gdm
select the display manager (LightDM, MDM, KDM, Slim, GDM) you want to use by default and hit enter
restart your computer

edited Aug 29 '18 at 17:47

abu_bua

10,783

answered Jun 25 '18 at 19:33

angelcervera

936

2

This worked for my MSI GS65 on Ubuntu 18.04. I also have to sudo prime-select nvidia and restart my computer -- doesn't work unless nvidia drivers are being used, it seems. – Russell Richie Sep 02 '18 at 20:08
Although it seems that, contra angelcervera's post, if I switch back to gdm3, the problem reappears.... – Russell Richie Sep 03 '18 at 17:08
In addition to this answer I renamed my xorg.conf, though don't know if that actually had any effect in the end. – dskrvk Sep 13 '18 at 01:38
Choosing lightdm instead of gdm3 worked for me on Ubuntu 18.04 after the latest updates introduced the problem... – nspo Nov 27 '18 at 20:24
Wow! Good catch. It worked when I changed to LightDM. Ubuntu 18.04 here. – Lupus Jan 09 '19 at 09:05
1

Note that it is the combination of gdm3 AND modesetting which causes this problem. Ubuntu 18.10 swapped to modesetting by default, this was later backported to 18.04. Nvidia modesetting stops tearing on the laptop panel because it enables 'prime synchronisation', a type of vsync for nvidia prime. But gdm3 gets very confused for some reason.
lightdm is the best of both worlds: working external monitors and tear-free nvidia graphics on the laptop's display.
– Tim Richardson Mar 13 '19 at 11:13
1

This doesn't solve the problem for me. GS65 and Ubuntu 18.04. – Thierry J. Mar 18 '19 at 14:52
I'm facing exactly the same problem on my Acer Predator with GTX 1060. Did this also "unblocked " yours driver settings? – Fabio Silva Apr 08 '19 at 13:27
Hi @FabioSilva I'm sorry, I don't understand what do you mean with "unblocked yours driver settings?" – angelcervera Apr 08 '19 at 13:54
@angelcervera in talking about the fact of you not being able to change the option "manually installed driver". To summarize, in talking about the image. Are you able to change this option after change your display monitor? – Fabio Silva Apr 08 '19 at 19:01
@FabioSilva Yes, I can. But I think that this issue is not related to the monitor detection. To manage drivers, I always use "ubuntu-drivers" from the console. – angelcervera Apr 09 '19 at 10:01
Doesn't work for me. – Mukul M. Jun 18 '19 at 20:02
@FactualHarmony My son is facing the same problem now. I think that this problem is too generic and depends on a lot of factors, so different versions of ubuntu packages means different problems. :( Search for more recent questions about the same. – angelcervera Jun 19 '19 at 07:57
Installing lightdm detected the monitors for me, but I got stuck in a login loop, reverting to gdm3 meant the monitors were no longer detected. The actual solution for me was a one line change to /lib/systemd/system/gdm3.service see my main answer in this thread, or the bug report where I found it here: https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1716857 – nhorning Aug 14 '19 at 20:06
Can confirm this works for Dell G5 5587 (PRIME) (Nvidia GTX 1050, Intel i7) Ubuntu 18.04 using nvidia 440 driver. LightDM was the only thing I needed. – Jordan Mackie Oct 21 '19 at 13:31
2

This worked for my MSI GS65 Stealth Thin 8RE laptop using Ubuntu 19.10. However, there's an extra information I'd add. Changing to lightdm using dpkg-reconfigure isn't possible if you haven't installed lightdm. If you face this issue, you might have to install it by running sudo apt-get install lightdm – xarlymg89 Nov 19 '19 at 14:06
1

sudo dpkg-reconfigure gdm3 and then choosing gdm3 solved it for me indeed (gdm3 was already my display manager before, I think). – talz Jun 29 '21 at 06:15

score 29 · Answer 4 · edited Oct 27 '22 at 17:08

29

There is a solution without installing lightdm!

Update:

It's apparently a better solution to run X11 as root. The one-line fix is to add this to this to /etc/X11/Xwrapper.config:

needs_root_rights = yes

It's a one line fix in /lib/systemd/system/gdm3.service

Replace

[Service]

ExecStartPre=/usr/share/gdm/generate-config

with

[Service]

ExecStartPre=/usr/bin/xinit /usr/share/gdm/generate-config

Found Here:

https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1716857

All my external displays are now detected and working on gdm3 My System:

Ubuntu 18.04.3 LTS

Lenovo T480

Intel® Core™ i7-8650U CPU @ 1.90GHz × 8

GeForce GTX 1070 Ti/PCIe/SSE2 via Razer Core X over Thunderbolt 3

GNOME 3.28.2

edited Oct 27 '22 at 17:08

Johann8

103

answered Aug 14 '19 at 19:16

nhorning

463

3

This should be the accepted answer. The one with most up votes suggests going back to older lightdm and is more steps. THis simple one line step fixes the issue for me. – user92240 Nov 25 '19 at 15:10
Xwrapper root rights worked for me too but I didn't have to change the gdm3.service setting. – Zoltán Süle Feb 22 '20 at 20:40
@nhorning I added needs_root_rights = yes to the file /etc/X11/Xwrapper.config and now the boot up of the device gets stuck between the decryption of the hard drive and the ubuntu login screen. – jrenk May 07 '20 at 09:50
The first part of this answer is the answer. Not sure what everything below the line is, but those parts are confusing. You should be alright with just adding needs_root_right = yes to /etc/X11/Xwrapper.config – Mr_Spock Aug 30 '20 at 22:00
1

I went into my etc/X11/Xwrapper.config and the line "needs_root_right = yes" was already sitting there. I have a lenovo extreme gen2, and working with pop_os. – Eren Mehmet Kiral Sep 18 '20 at 14:30
1

This doesn't work for me. Probably the reason for the upvote difference @user92240 – Yash Jakhotiya Oct 17 '21 at 19:21
1

No luck - Ubuntu 20.04 on ThinkPad P1 Gen3 – Chris Hayes Oct 23 '21 at 19:50
The update section of this answer was all I needed. Thanks! – PoJam Oct 08 '22 at 09:59
works for me even with intel graphics – Peter Chung Mar 25 '23 at 05:49
now my system didn't boot up and stock in loading! – Mosi Feb 07 '24 at 09:07

score 8 · Answer 5 · answered Jun 23 '19 at 18:04

I attempted the solution that says to reconfigure to lightdm but that did not seem to work.

I did some reading from the following website: https://devtalk.nvidia.com/default/topic/1035768/linux/ubuntu-18-04-can-t-see-second-monitor/ and I found that at least on the Lenovo Legion Y530 the solution is to change the NVIDIA prime profile from intel to nvidia and then restart the computer.

You can switch the profiles by going to 'NVIDIA X Server' settings, going to the 'PRIME profiles' tab and then selecting 'NVIDIA (performance mode)'. After, restart the computer.

You can also reconfigure the PRIME profiles tab by running the following command in the terminal.

 sudo prime-select nvidia

and then restarting your computer.

In my case, nvidia was already selected, but it started working when selecting "intel". Then I selected back "nvidia" with no problems. — dvlcube, Jun 06 '20 at 04:09

score 6 · Answer 6 · answered Nov 19 '18 at 10:45

6

My external monitor plugged into my Lenovo L380 HDMI stopped working on Ubuntu 18.04. I succeeded to fix this issue by opening the BIOS setup and changing the display priority option from the USB Type-C to the HDMI.

answered Nov 19 '18 at 10:45

Sergii Golubev

161
1
3

My lenovo E14 is not having disply priority, it is just display with option to select either of laptop display, hdfmi or usb. what to do ? – Sandeep Balagopal Sep 11 '20 at 14:35
1

@SandeepBalagopal IMO, try selecting HDMI, but remember the sequence of buttons to press to revert this change ) In case your laptop fails to fallback to the laptop display if it doesn't find the HDMI display – Sergii Golubev Sep 14 '20 at 10:24

score 5 · Answer 7 · answered May 30 '18 at 00:09

5

Try this (change resolution, if 1920x1080 is not your resolution):

    xrandr --addmode HDMI-1-1 1920x1080
    xrandr --output HDMI-1-1 --mode 1920x1080

answered May 30 '18 at 00:09

Mihai R

139
1
5

score 5 · Answer 8 · edited Dec 28 '19 at 15:42

5

I could connect to external monitor before i execute

sudo apt install gnome

I tried suggestions above, but none of them works. at last I recover the connection by this

sudo service gdm3 restart
sudo reboot

wired.

edited Dec 28 '19 at 15:42

askepott

103

answered Aug 20 '19 at 06:49

vincewl

51

restarting gdm3 resolved the problem. – Vignesh_A Sep 25 '20 at 05:23
after trying many other things in this thread, this is the one that worked for me. However, it changed completely the appearance of my login screen. – Santiago Oct 27 '20 at 08:55
Tried a bunch but this one finally did the job - thanks a ton – Display name Jul 07 '21 at 22:58
I have connect 2 screen, Now after installing gnome as described, issue is was resolved thanks. – vidur punj Jan 16 '23 at 15:41

score 5 · Answer 9 · edited Nov 04 '19 at 20:12

5

I had the same issue on an my Asus ROG laptop (running Ubuntu 19.04 / Windows 10 dual boot) after a BIOS update.

First I had to disable secure boot in BIOS.

Then I had to set options nvidia-drm modeset=0 in /lib/modprobe.d/nvidia-kms.conf and run sudo update-initramfs -u.

edited Nov 04 '19 at 20:12

Eliah Kagan

117,780

answered Nov 04 '19 at 17:09

Arctodus

151

score 5 · Answer 10 · answered Dec 16 '19 at 17:41

5

People who are still struggling to setup your external monitor with Ubuntu 18.04. Just disable Secure Boot at the BIOS settings and give it a try. It worked for me. (ASUS ROG G531GV)

answered Dec 16 '19 at 17:41

Danuja

51

score 5 · Answer 11 · answered Jan 30 '20 at 11:41

5

I had similar problem, played with UEFI & Legacy boot mode, searched for hours but finally got it done by following ways: 1. goto Software & Updates 2. Additional Drivers 3. Changed the display driver from there. 4. restart

answered Jan 30 '20 at 11:41

rraj gautam

171

This worked for me in the sense that now my Ubuntu 20 Legion detects my external monitors, but the problem is that the image on the external monitors (but not the main monitor) is all scrambled (not during booting but after X server loads). – patapouf_ai Mar 07 '22 at 16:08

score 5 · Answer 12 · answered Feb 28 '20 at 16:00

Besides following this answer above, I followed instructions here. More specifically, step 1 of that told me the recommended drivers for Ubuntu 18.04.1

15:~$ ubuntu-drivers devices
== /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0 ==
modalias : pci:v000010DEd00001C8Csv00001028sd00000798bc03sc00i00
vendor   : NVIDIA Corporation
model    : GP107M [GeForce GTX 1050 Ti Mobile]
driver   : nvidia-driver-415 - third-party free
driver   : nvidia-driver-390 - third-party free
driver   : nvidia-driver-410 - third-party free
driver   : nvidia-driver-440 - third-party free recommended
driver   : nvidia-driver-435 - distro non-free
driver   : xserver-xorg-video-nouveau - distro free builtin`

Then a apt install nvidia-driver-440 & I was finally home.

score 4 · Answer 13 · answered Nov 20 '18 at 16:04

The top solution did not work for me on my Acer laptop, which suddenly stopped showing HDMI-1 as an output in xrandr this morning. I tried changing to the noveau drivers in case that helped, but it didn't.
I read on a different site that sometimes the OEM laptop Nvidia cards can "get confused whether cable is connected or not", which I had assumed was just tech-support appeasing someone. But, for giggles, I tried unplugging the HDMI cable, plugging in the VGA cable, rebooting, and plugging the HDMI cable back in. For some reason, that worked.

This is probably an extension of "Just Learning"'s solution, the important part of which is probably the "through VGA" part.

Also try using another cable, that was my issue... it was the cable not the software or hardware :-| — brasofilo, Jan 28 '22 at 01:50

score 2 · Answer 14 · answered Dec 13 '18 at 07:56

I did not have this problem on Ubuntu 18.04 with NVIDIA GeForce GTX 1050 Mobile and GeForce GTX 1050. But after upgrading my kernel to 4.19 my external monitor was not detected anymore. Reverting back to the standard 4.15 kernel made the problem disappear.

score 2 · Answer 15 · answered May 17 '19 at 03:48

Tried everything related from gdm3, lightdm, i3, nvidia drivers purge & reinstallation. What worked for me was to go to /etc/X11/ folder and create a xorg.conf file with file contents:

Section "ServerLayout"
Identifier "layout"
Screen 0 "nvidia"
Inactive "intel"
EndSection

Section "Device"
Identifier "intel"
Driver "modesetting"
BusID "PCI:0@0:2:0"
Option "AccelMethod" "None"
EndSection
Section "Screen"
Identifier "intel"
Device "intel"
EndSection

Section "Device"
Identifier "nvidia"
Driver "nvidia"
BusID "PCI:1@0:0:0"
Option "ConstrainCursor" "off"
EndSection

Section "Screen"
Identifier "nvidia"
Device "nvidia"
Option "AllowEmptyInitialConfiguration" "on"
Option "IgnoreDisplayDevices" "CRT"
EndSection

And then reboot. I did not have success in Wayland but it worked in the Unity version.(I am running 18.04 in Alienware R313 with dualboot Windows)

This gave me a PKCS#7 error when booting so I had to disable the driver to enter and remove the file. — Francisco Peters, May 27 '19 at 16:20
I think you might be able to get the same result in gdm3 by changing one line in /lib/systemd/system/gdm3.service
See my main answer in this thread or the original bug report https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1716857 — nhorning, Aug 14 '19 at 19:57

diadochos · Answer 16 · 2019-10-16T01:59:59.223

For me, the solution found here was the only thing that worked.

$ sudo apt install intel-gpu-tools
$ intel-virtual-output
$ reboot

My setup is:

MSI GS65 Stealth 8SF
Ubuntu 18.04 LTS (Budgie Desktop 18.04)

Update

I noticed that the second display correctly shows after reboot, but no longer does it after suspension. Above was not what seemed to do the trick, but it seems that it's just the reboot that has helped.

score 2 · Answer 17 · answered Oct 20 '19 at 13:54

I just spent several hours trying may different solutions I found on this thread and elsewhere online.

I'm running Ubuntu 18.04 on HP Elitebook with Nvidia GTX1050 graphics card. After a fresh install everything worked except external monitor. I switched the nvidia driver in the Additional Drivers section of Software & Updates several times and everytime before the switch got completed I had to choose some password that I'd supposedly use during the next reboot, but I never got asked for it during the actual reboot.

The reason the external display didn't work, was that the selected drivers didn't get loaded. I found that out by running nvidia-settings in the terminal and getting a "ERROR: NVIDIA driver is not loaded" response.

The solution: Pay attention at reboot for Enrol MOK key/MOK management screen. There select the option to Enroll key and type the password you created during driver update in Ubuntu.

All works perfect after this.

patapouf_ai · Answer 18 · 2022-03-08T17:37:04.073

I personally needed to a combination of many of the other answers for it to work for me on Ubuntu 20.04.4 LTS on a Lenovo Legion with AMD with radeon graphics card and Nvidia gpu. It also fails with linux kernel 5.13.0-30 but works with kernel 5.13.0-28 for some weird reason:

(1)

sudo apt-get purge 'nvidia*'
sudo add-apt-repository ppa:graphics-drivers
sudo apt-get update
sudo ubuntu-drivers autoinstall

Then reboot. The above ended up installing nvidia-driver-510 for me.

Very important: for the above to work to work, you need to either first disable secure-boot or make sure that on the next boot you do not simply boot normally but rather you accept the mok/lok key first.

(2)

Make sure /etc/X11/Xwrapper.config contains the line: needs_root_rights = yes

(3)

set options nvidia-drm modeset=0 in /lib/modprobe.d/nvidia-kms.conf and run sudo update-initramfs -u then reboot

(4) [finally]

Change grub to load without nomodeset: Edit line GRUB_CMDLINE_LINUX_DEFAULT in file /etc/default/grub to remove nomodeset in for example: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset"

Reboot.

Hopefully a combination of these should solve your problem. This problem reappears regularly (often after rebooting after updates) for me, so I am keeping the solutions that worked for me here.

While this seemed to not work for me initially. When I switched to step 4 I discovered that I already have no nomodeset for grub (most probably from previous time I fixed this ssue). Rebooted anyway. Had no 2nd monitor. I don't no why, but decided to power off-> power on. Logged in. Everything started to work.
Laptop, MSI GS75 Stealth 9SF (RTX 2070), Ubuntu 22.04.4 LTS — zanshin13, Mar 15 '24 at 09:12

score 0 · Answer 19 · answered Jul 18 '19 at 10:31

0

For me I had to turn on Legacy mode support in BIOS.

answered Jul 18 '19 at 10:31

geras · Answer 20 · 2019-08-27T08:43:49.647

For me this problem occurred on a Lenovo Ideapad 510 running Ubuntu 16.04 after connecting to a different than usual external monitor via HDMI. It got fixed after I had connected this laptop to yet another external monitor, although it hadn't worked there. Earlier I also changed my graphics drivers from open-source to proprietary and then to open-source again--maybe this helped. I also restarted my computer several times. It seems pretty random.

score 0 · Answer 21 · answered Sep 13 '19 at 13:53

0

One quick extra check is that you don't have nomodeset or vga= as kernel parameters, as noted here (the link is for Radeon but I guess similar would apply to other graphics hardware). Removing nomodeset just fixed a similar problem for me.

Instructions for how to check and if necessary edit your kernel parameters as applied at boot time can be found on this page.

answered Sep 13 '19 at 13:53

Alan H

1

How would that matter after it switches from text mode to graphics mode? – 0xC0000022L May 04 '21 at 21:09

score 0 · Answer 22 · answered Dec 05 '19 at 22:01

I tried many things to solve this problem and someone finally helped me out. My issue was with the NVIDIA drivers and this line solved it.

sudo apt install nvidia-driver-435

Link to my issue here (Ubuntu 18.04.3 cant find second monitor - Dell G3 - NVIDIA 1060 TI)

score 0 · Answer 23 · answered Dec 15 '19 at 04:38

0

I just purchased a brand new Dell 5493 with i7 and Intel Graphics card. Had the same issue, no HDMI or monitor detected after installing Ubuntu 18.04 dual boot with Windows 10. Upgrading to the newest kernel solved the issue.

answered Dec 15 '19 at 04:38

zhijaz

1

How did you update to latest kernel? any specific commands or website that you followed. – Vignesh_A Sep 25 '20 at 05:24

score 0 · Answer 24 · answered Jan 21 '20 at 09:06

I removed my laptop's battery for a while, and then it worked again. This is a 'known' fix at my company; employed commonly.

So for me specifically the problem was that secondary monitors were always detected, up until I rebooted and it suddenly didn't anymore.

score 0 · Answer 25 · answered Jul 25 '20 at 05:05

I have an MSI Prestige 15.6" Laptop with a GeForce GTX 1650 Mobile / Max-Q graphics card and a built-in Intel vga controller. I'm running Ubuntu 18.04. I use two 1080p external monitors one connected to the HDMI port and one connected through a USB-C hub. All 3 monitors worked before installing the Nvidia driver.

I installed the 440 driver and after that the laptop would not recognize the monitor connected via the HDMI port. It was like the HDMI port didn't work any more. (I enabled the MOK per the driver installation instructions.)

If I switched back to the X.org Nouveau driver (through Software & Updates, Additional drivers) then all 3 monitors work properly. If I switch back to either the 440 or 435 driver the monitor connected to HDMI doesn't work.

I've tried several of the recommendations in this thread and none of them work. The Nvidia drivers simply don't work on this hardware with the 5.3 kernel.

I have an old desktop with a 960 in it that I'll go back to using for the little bit of CUDA development that I have to do.

I post this FYI for anyone else running into this.

score 0 · Answer 26 · answered Feb 08 '21 at 18:38

0

Something that worked for me for a similar problem was lower the refresh rate of the monitor through the display settings on Ubuntu.

answered Feb 08 '21 at 18:38

Carson Wood

111

score 0 · Answer 27 · answered Dec 09 '21 at 11:44

No solutions from here worked for me. I solved the problem by disabling UEFI mode in BIOS.

restart
press [Esc] to enter GRUB menu
select [System configuration], computer enters BIOS setup
go to [Boot] menu
Disable UEFI there everywhere (two places in my case were replaced with 'Legacy' option)
Save changes & exit, system restarts.

Now plugged monitors are detected.

score 0 · Answer 28 · answered Jun 01 '22 at 05:50

I am on ubuntu 22.04 LTS. For me this worked for me. First followed answer from - https://askubuntu.com/a/1099736

ie:

sudo apt-get purge 'nvidia*'
sudo add-apt-repository ppa:graphics-drivers
sudo apt-get update

Then reinstall the Nvidia card driver Answer from - https://askubuntu.com/a/1074337

sudo ubuntu-drivers autoinstall

Then restart the System and connect the monitor

score 0 · Answer 29 · answered Jun 19 '22 at 16:05

0

This simple solution worked for me:

sudo apt dist-upgrade

then

sudo reboot

answered Jun 19 '22 at 16:05

vikrant

807

score -3 · Answer 30 · answered May 22 '18 at 09:05

-3

I connected my external monitor through VGA and went to Settings > Devices > Displays choose Mirror and then Apply. was asked if I wanted to keep this Setting choose Yes and everything connected. Simple and Beautiful.

answered May 22 '18 at 09:05

Just Learning

1

2

Unfortunately, the default settings app was the very first thing I tried. That being said, perhaps someone else will find this advice useful! (My problem has been solved, by the way, although I'm not entirely sure how...) – PullJosh May 22 '18 at 20:56

External monitor not detected on Ubuntu 18.04

30 Answers30

Found Here:

All my external displays are now detected and working on gdm3 My System:

Update

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