I am writing an article about multi-monitor setup and usage on Ubuntu/Linux. I’ll also add a few tips that one can use while using the multimonitor setup like:
- Different wallpaper on each monitor
- top panel on each monitor
- Shortcut to move an application to another monitor
These are just a few examples. If you are using a multiple monitor setup, do you have some suggestions or tips that you use? Please share it here and I’ll include them in the article on It’s FOSS.
I don’t know if you could count that as a “tip”, but I definitely advise people to use the original drivers provided by the manufacturer, because they are usually far superior to nouveau. The last time I installed Debian with KDE on my computer it even lagged (I have a GTX 970 + i7-8700K …), probably partially due to my 5 connected monitors. Once I installed the original NVIDIA driver’s newest version, everything runs smoothly.
Additionally, you need to make sure that the driver is actually recognizing each monitor correctly during the X-config creation. If just 1 monitor is falsely added to the list then you have to stay on command line. If someone encounters such an issue, then they should completely purge all X elements (including nouveau) and then freshly install the original driver.
If someone is trying to troubleshoot a display problem, but they keep booting into a black screen, I also advise to add a boot parameter to the GRUB2 entry of the OS. That usually helped me a lot. Here an explanation:
The newest kernels have moved the video mode setting into the kernel. So all the programming of the hardware specific clock rates and registers on the video card happen in the kernel rather than in the X driver when the X server starts… This makes it possible to have high resolution nice looking splash (boot) screens and flicker free transitions from boot splash to login screen. Unfortunately, on some cards this doesnt work properly and you end up with a black screen. Adding the nomodeset parameter instructs the kernel to not load video drivers and use BIOS modes instead until X is loaded.
I also described for beginners how to add the nomodeset parameter temporarily manually here.
That’s a great idea, I’ve been using my personal laptop at work when I have to do a presentation (and I do that a lot). But when I connect my HP with Kubuntu via HDMI on a TV the resolution is too big and I can’t seem to fix it by fitting the entire screen. That is when I’m remotely connected to my PC at work via KRDC remote desktop.
This is not a “tip” - just thought I’d mention an ugly glitch I’m having with a multiple monitor setup at work :
Ubuntu 18.04.1 on a Dell E7250 (16 GB RAM 512 mSATA SSD - 1366x768 screen)
Dell docking station
2 x Dell 24" monitors attached via displayport to docking station
The monitors will blink and go black for a few seconds “every so often” (maybe once an hour? no rhyme or reason - but seems to happen more often when the machine is busy [e.g. booting a VM in virtualbox] and playing music at the same time… most times they come back on - sometimes they stay off (and screens complain about no signal) - and I have to either undock, or unplug one of the monitor’s DP leads from the docking station, then reconnect… it’s a PITA… I’ve rebuilt the laptop from scratch and same issue… everything I’ve read seems to point to the operating system trying to do “sound” over displayport… some fixes seem to be to “mute” that displayport/HDMI sound device (didn’t work)… another fix? plug 3.5 mm headphones into one of the headphone ports - nada - doesn’t fix… nothing seems to fix it! I’ve replaced the docking station too!
It never happens when I dock the Windows 10 laptop on my desk (but I barely ever use it as I detest using Windows) to the same docking station/monitor setup…
I’ve got multiple monitor setups at home - even odd monitor combinations - e.g. my gaming “rig” desktop machine (Phenom II X6, 12 GB RAM GTX650ti - proprietary drivers) has a 24" 1680x1050 and a 19" 1280x1024 - no problems at all…
And for a while I used this same Dell laptop at home on a docking station, with 2 x 24" Dell monitors - the only difference being that only one of them was using displayport and the other DVI… so it would seem uniformity is more problematic than diversity!
Now that you have pointed it out, I think I also experienced something similar. One of my external monitor flickers and the screen goes black for a couple of seconds. It happens once in a few hours but since it’s for a very short span of time, I didn’t pay attention to it.
Update - two rebuilds later - and the same issue…
elementary 5.0 juno - screens blanking for a few seconds every half hour or so…
Xubuntu 18.04.1 - screens blanking for a few seconds every half hour or so…
If anything - it’s slightly worse in Xubuntu (although I didn’t try elementary for very long) - i.e. worse than it was on “plain” vanilla Ubuntu 18.04.1 - someomes the monitors won’t come back on - and when they don’t I have to disconnect the displayport from the back of the docking station, and plug it back in - then - the monitors seem to rearrange themselves into some random configuration, and I have to fire up the Display applet in the Settings Manager… with Ubuntu “gnome” - it always remember the correct layout of the monitors - XFCE seems to keep forgetting it…
I wish some people with 3+ monitors would weigh in on this topic. Especially regarding the simultaneous use of integrated and dedicated GPUs on Linux.
I use 3 monitors. the main reason I have a 3 monitor set up is because I use xplane11 (flight simulator).
I’m no expert, I use Manjaro Linux and I have an Nvidia GTX680. I can only say what’s previously been said, stick with the manufacturers drivers. The hardest thing I had to do configuration wise, was get the monitors in the correct order. I remember the days when you’d have to jump through hoops backwards to set up two monitors. These days, the options are just there.
I used to play Serious Sam III (Linux version in Steam) across three identical monitors (Samsungs 19") - all 4:3 ratio for that “surround” look… it worked flawlessly with a NVidia GTX650Ti OC using proprietary drivers… So - three monitors never been a problem with desktop computer running “recent” Ubuntu versions for me…
Still having issues with my Ubuntu laptop at work and 2x DisplayPort 1080p monitors - they flicker and blank (and sometimes turn off)… it does seem related somehow to Ubuntu (and other distros I’ve tried) trying to send Audio over the DisplayPort cables… I’ve tried all sorts of things I’ve found in searches…
Here’s one thing that’s DRIVING ME NUTS! I’ve installed pavucontrol (sudo apt install pavucontrol) and I go to the “Configuration” tab and set the top option “Built-In Audio” to “Off” (this is the HDMI/Displayport audio settings) :
Then about “n” minutes later (could be 5, could be 2, could be 2 hours!) - my screen(s) both, or just one, will go blank for a few seconds (or go into powersave mode) - and sure enough - I open pavucontrol (I keep it running all the time) - and it’s F–KING reverted to allowing “Digital Stereo (HDMI) Output” again!!!
This is driving me potty! Why bother having those options to choose, if it will just seemingly, arbitrarily or randomly, make a decision counter to my wishes???
Anyway - hopefully this will “go away” when I replace this laptop with an RPi4 when it arrives (if ever)…
Update : kinda “fixed” it…
My “bench neighbour” - i.e. I sit on a row of benches with our workstations/laptops for work - moved one desk place further down - leaving a new docking station and different pair of Dell monitors (different models to the ones I was using) - so I swapped out the docking stations and the monitors - problem gone… I suspect it’s the monitors - as I’d already tried swapping docking stations… pretty sure it was audio trying to play on the displayport connection, as it happened way more often when I was playing music (which I do nearly all day)…
Two days - no more flicker or screen-blanking!