Unable to use external monitor

dg.aragones · 06-01-2019, 10:17 AM

Hello all,

I have problems using external monitors with Ubuntu 18.04. I use an HP laptop and I want to connect two different external monitors, one that I have at home (LG) and one that I have at work (Dell). In the two cases I have the same issue: the laptop's screen turns black and never connects.

Any idea how can I do this?

Thank you in advance for any help!

fatmac · 06-01-2019, 10:44 AM

Usually, you have a function key that lets you decide whether to use external only, or both at the same time.

dg.aragones · 06-01-2019, 10:55 AM

Quote:

Originally Posted by fatmac

Usually, you have a function key that lets you decide whether to use external only, or both at the same time.

The laptop just gets blocked and doesn't respond to any key or the mouse.

flshope · 06-01-2019, 06:28 PM

I have a 2008 HP 2133 Mini-note laptop running Ubuntu 16.04. The only window manager that works on it so far is IceWM. The Ubuntu and Gnome Flashback managers won't even start up. With IceWM, I found that if I log on, I only get the laptop display. If I wait a few minutes, log off, and then log on again, the external display will come on, too. The Fn+F2 key combination given in the manual doesn't do anything. Under 14.04, Fn+F2 activated the external display but blanked the laptop screen.

frankbell · 06-01-2019, 08:21 PM

Is the external monitor connected at time of boot? Have you tested the cable with another setup to verify that the cable is good?

If it's not, it may not get properly detected.

dg.aragones · 06-02-2019, 06:51 AM

Quote:

Originally Posted by frankbell

Is the external monitor connected at time of boot? Have you tested the cable with another setup to verify that the cable is good?

If it's not, it may not get properly detected.

The cable and the monitor are both working ok. I've tested them with other laptop using Windows 10.

If I connect the external monitor at time of boot it's initially detected and I can see the same in the two screens, but then Ubuntu never finishes to start.

ondoho · 06-04-2019, 12:12 AM

Quote:

Originally Posted by dg.aragones

If I connect the external monitor at time of boot it's initially detected and I can see the same in the two screens, but then Ubuntu never finishes to start.

that's weird.
output of

Code:

lspci -k | grep -iEA5 'vga|3d|display'

please

and

Code:

xrandr

for different scenarios.

dg.aragones · 06-04-2019, 08:40 AM

Quote:

Originally Posted by ondoho

that's weird.
output of

Code:

lspci -k | grep -iEA5 'vga|3d|display'

please

and

Code:

xrandr

for different scenarios.

It's weird yes...

Code:

lspci -k | grep -iEA5 'vga|3d|display'
00:02.0 VGA compatible controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 07)
	Subsystem: Hewlett-Packard Company Mobile 4 Series Chipset Integrated Graphics Controller
	Kernel driver in use: i915
	Kernel modules: i915
00:02.1 Display controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 07)
	Subsystem: Hewlett-Packard Company Mobile 4 Series Chipset Integrated Graphics Controller
00:1a.0 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #4 (rev 03)
	Subsystem: Hewlett-Packard Company 82801I (ICH9 Family) USB UHCI Controller
	Kernel driver in use: uhci_hcd
00:1a.1 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #5 (rev 03)

Code:

Screen 0: minimum 320 x 200, current 1366 x 768, maximum 8192 x 8192
LVDS-1 connected primary 1366x768+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
   1366x768      59.64*+
   1360x768      59.80    59.96  
   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  
VGA-1 disconnected (normal left inverted right x axis y axis)
HDMI-1 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)
SVIDEO-1 disconnected (normal left inverted right x axis y axis)

TB0ne · 06-04-2019, 08:57 AM

Quote:

Originally Posted by dg.aragones

Hello all,
I have problems using external monitors with Ubuntu 18.04. I use an HP laptop and I want to connect two different external monitors, one that I have at home (LG) and one that I have at work (Dell). In the two cases I have the same issue: the laptop's screen turns black and never connects.

Any idea how can I do this? Thank you in advance for any help!

Would help to know any useful details about your laptop. Just telling us "HP Laptop", isn't much to go on...what model? How is the second monitor attached (HDMI? DisplayPort? DisplayLink??)

Your system lists VGA, HDMI, DisplayPort, and SVideo. And are you using any adapters on the cable? Because there is a difference between passive adapter and an active CONVERTER.

dg.aragones · 06-04-2019, 10:59 AM

Quote:

Originally Posted by TB0ne

Would help to know any useful details about your laptop. Just telling us "HP Laptop", isn't much to go on...what model? How is the second monitor attached (HDMI? DisplayPort? DisplayLink??)

Your system lists VGA, HDMI, DisplayPort, and SVideo. And are you using any adapters on the cable? Because there is a difference between passive adapter and an active CONVERTER.

It's an HP 620. The monitor can be attached using VGA and HDMI. In both cases I have the same issue. I'm not using any adapter or converter, just a direct cable between the laptop and the monitor.

I hope this information can be useful.

TB0ne · 06-04-2019, 11:09 AM

Quote:

Originally Posted by dg.aragones

It's an HP 620. The monitor can be attached using VGA and HDMI. In both cases I have the same issue. I'm not using any adapter or converter, just a direct cable between the laptop and the monitor.

Have you applied the updated drivers for the Intel graphics you have? And apparently, this is a known bug in 18.04:
https://bugs.launchpad.net/ubuntu/+s...x/+bug/1813663

You can also try a temporary fix (after you boot up with single-display) of:

Code:

xrandr --addmode VGA-1 1366x768
xrandr --output VGA-1 --mode 1366x768 --right-of LVDS-1

..and see if it works. Of course, modify the "right-of" to "left-of" if needed.

dg.aragones · 06-04-2019, 11:20 AM

Quote:

Originally Posted by TB0ne

Have you applied the updated drivers for the Intel graphics you have? And apparently, this is a known bug in 18.04:
https://bugs.launchpad.net/ubuntu/+s...x/+bug/1813663

You can also try a temporary fix (after you boot up with single-display) of:

Code:

xrandr --addmode VGA-1 1366x768
xrandr --output VGA-1 --mode 1366x768 --right-of LVDS-1

..and see if it works. Of course, modify the "right-of" to "left-of" if needed.

Thank you for your reply!

I don't know if I've applied the updated drivers... How can I do this?

Yes, it might be a bug in Ubuntu 18.04. I've also problems with the screen when I close it and open it back.

I've tried the temporary fix that you propose but it didn't work. Just both screens (laptop and monitor) turned blank.