Need help configuring dual monitors

[clarkleach]

Whatever. Sorry I asked.

[GarryRicketson]

For me, this was pretty straight forward and easy to follow.
https://pkg-xorg.alioth.debian.org/howt ... randr.html
I did not have any problems. How ever any way,

I did a search :
help configuring dual monitors with xrandr on Debian

There have been others that have had similar problems,
https://unix.stackexchange.com/question ... -on-debian

I had this problem, and it had nothing to do with xfce or debian, I didn't have some firmware, so I did this :
dpkg -i firmware-linux-nonfree_0.43_all.deb

Find the firmware here or here:

Postby clarkleach »This, it would seem, rules out any hardware or BIOS issues.
Any idea what is so different between Kubuntu and Debian/KDE?

The big difference is Kubuntu , Ubuntu, and many other distros are easier
for people new to Linux to install, and "just works", they usually include the non-free drivers or firm ware. And that is where so many people have problems
with Debian, sometime it does take some extra effort installing these.
Since it does work on Kubuntu, that does show it can work on your computer,
it may not directly be "hardware", but with out the proper firmware , and/or drivers , the hardware will not work properly,..
Another good distro to start out with is"MX-16"
it usually "just works", it ships with XFCE, but KDE can be installed after.
There also several threads on the Dual Monitors, problem here on the forum,
as well as in the search results,...

Postby clarkleach »Again, any help would be greatly appreciated even if it is simply pointing me to a more suitable forum.

There are several forums, where this same question has been asked, as shown in the search results:
https://unix.stackexchange.com/question ... -on-debian
====================
The problem is , often when it is a question that has been asked often, and there are many answers, discussions, they don't accept the question, like we do here.
The "arch wiki" is usefull as well :
https://wiki.archlinux.org/index.php/multihead
They also have a forum, I don't know if the OP would find it "more suitable" though.
======================
Forums for Debian , and xrandr , dual monitors
Might be usefull, but is pretty old:
https://forum.siduction.org/index.php?topic=3782.0

What is the output ?:

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xrandr -q 

----

Now try:

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xrandr --output LVDS --auto --output VGA-O --auto --left-of LVDS 

Are there any errors ?

[clarkleach]

First, thank you for getting this thread back on topic.
Second, I apologize for letting my frustration get the best of me and ranting.

One curious factoid that may or may not be relevant - I swapped which ports the monitors were connected to because it was making things too confusing in Kubuntu. Now, when booting into Debian, only one monitor is active; the other gets no signal at all. Weird.

So, from Debian I get the following from xrandr and inxi:

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xrandr: Failed to get size of gamma for output default
Screen 0: minimum 2560 x 1440, current 2560 x 1440, maximum 2560 x 1440
default connected primary 2560x1440+0+0 0mm x 0mm
   2560x1440     93.00* 

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System:    Host: ML10-Debian Kernel: 3.16.0-4-amd64 x86_64 (64 bit) Desktop: KDE 4.14.2 
           Distro: Debian GNU/Linux 8 
Machine:   Mobo: HPE model: ML10Gen9 v: (null) Bios: American Megatrends v: 1.004 date: 09/13/2016
CPU:       Quad core Intel Xeon E3-1225 v5 (-HT-MCP-) cache: 8192 KB 
           Clock Speeds: 1: 800 MHz 2: 800 MHz 3: 800 MHz 4: 3301 MHz
Graphics:  Card: Intel Device 191d
           Display Server: X.Org 1.16.4 drivers: fbdev,intel (unloaded: vesa)
           Resolution: 2560x1440@93.00hz
           GLX Renderer: Gallium 0.4 on llvmpipe (LLVM 3.5, 256 bits) GLX Version: 3.0 Mesa 10.3.2
Network:   Card: Intel Ethernet Connection (2) I219-LM driver: e1000e
           IF: eth0 state: up speed: 100 Mbps duplex: full mac: 94:18:82:08:fd:f1
Drives:    HDD Total Size: 1000.2GB (3.5% used) ID-1: /dev/sda model: ST1000DM010 size: 1000.2GB
Partition: ID-1: / size: 457G used: 4.3G (1%) fs: ext4 dev: /dev/sda2 
           ID-2: swap-1 size: 21.37GB used: 0.00GB (0%) fs: swap dev: /dev/sda3 
Sensors:   System Temperatures: cpu: 29.8C mobo: 27.8C 
           Fan Speeds (in rpm): cpu: N/A 
Info:      Processes: 177 Uptime: 33 min Memory: 1910.2/20025.1MB Client: Shell (bash) inxi: 2.1.28 

from Ubuntu:

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Screen 0: minimum 320 x 200, current 5120 x 1440, maximum 8192 x 8192
DP-1 connected primary 2560x1440+0+0 (normal left inverted right x axis y axis) 597mm x 336mm
   2560x1440     59.95*+
   1920x1080     60.00    50.00    59.94  
   1920x1080i    60.00    50.00    59.94  
   1680x1050     59.95  
   1280x1024     75.02    60.02  
   1440x900      59.89  
   1280x960      60.00  
   1280x720      60.00    50.00    59.94  
   1024x768      75.03    70.07    60.00  
   832x624       74.55  
   800x600       72.19    75.00    60.32    56.25  
   720x576       50.00  
   720x480       60.00    59.94  
   640x480       75.00    72.81    66.67    60.00    59.94  
   720x400       70.08  
HDMI-1 disconnected (normal left inverted right x axis y axis)
DP-2 connected 2560x1440+2560+0 (normal left inverted right x axis y axis) 597mm x 336mm
   2560x1440     59.95*+
   1920x1080     60.00    50.00    59.94  
   1920x1080i    60.00    50.00    59.94  
   1680x1050     59.95  
   1280x1024     75.02    60.02  
   1440x900      59.89  
   1280x960      60.00  
   1280x720      60.00    50.00    59.94  
   1024x768      75.03    70.07    60.00  
   832x624       74.55  
   800x600       72.19    75.00    60.32    56.25  
   720x576       50.00  
   720x480       60.00    59.94  
   640x480       75.00    72.81    66.67    60.00    59.94  
   720x400       70.08  
HDMI-2 disconnected (normal left inverted right x axis y axis)

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System:    Host: Kubuntu-ML10Gen9 Kernel: 4.8.0-51-generic x86_64 (64 bit) Desktop: KDE Plasma 5.5.5
           Distro: Ubuntu 16.04 xenial
Machine:   Mobo: HPE model: ML10Gen9 v: (null) Bios: American Megatrends v: 1.004 date: 09/13/2016
CPU:       Quad core Intel Xeon E3-1225 v5 (-HT-MCP-) cache: 8192 KB 
           clock speeds: max: 3700 MHz 1: 3043 MHz 2: 912 MHz 3: 1119 MHz 4: 899 MHz
Graphics:  Card: Intel Device 191d
           Display Server: X.Org 1.18.4 drivers: (unloaded: fbdev,vesa)
           Resolution: 2560x1440@59.95hz, 2560x1440@59.95hz
           GLX Renderer: Mesa DRI Intel HD Graphics P530 (Skylake GT2) GLX Version: 3.0 Mesa 12.0.6
Network:   Card: Intel Ethernet Connection (2) I219-LM driver: e1000e
           IF: eno1 state: up speed: 100 Mbps duplex: full mac: 94:18:82:08:fd:f1
Drives:    HDD Total Size: 1000.2GB (3.0% used) ID-1: /dev/sda model: ST1000DM010 size: 1000.2GB
Partition: ID-1: / size: 441G used: 9.4G (3%) fs: ext4 dev: /dev/sda4
           ID-2: swap-1 size: 21.37GB used: 0.00GB (0%) fs: swap dev: /dev/sda3
RAID:      No RAID devices: /proc/mdstat, md_mod kernel module present
Sensors:   System Temperatures: cpu: 29.8C mobo: 27.8C
           Fan Speeds (in rpm): cpu: N/A
Info:      Processes: 201 Uptime: 3 min Memory: 749.6/19980.5MB Client: Shell (bash) inxi: 2.2.35 

I definitely see a difference in the driver configuration. I'm not entirely sure how to interpret this information or how to deal with it.
What does "firmware" mean, exactly, in this context? On my planet (where I program microcontrollers and stuff) it means code programmed into a non-volatile memory somewhere, usually flash or eprom.

Based on this information, can you recommend a course of action? It looks like removing some intel drivers may be in order?

[pkladisios]

In ubuntu, you get a normal xrandr output. It sees both your connected monitors (through the interfaces DP-1 and DP-2). On the other hand, debian displays an error. It might have something to do with your display drivers. I found similar, albeit not identical, topics:
http://forums.debian.net/viewtopic.php?f=5&t=111521
http://forums.debian.net/viewtopic.php?f=5&t=81007

[clarkleach]

In ubuntu, you get a normal xrandr output. It sees both your connected monitors (through the interfaces DP-1 and DP-2). On the other hand, debian displays an error. It might have something to do with your display drivers.

I'm pretty certain it has everything to do with drivers. Now I just need to figure out how to remove xorg drivers and install intel drivers...

[debiman]

I'm pretty certain it has everything to do with drivers.

that, and kernel versions. maybe you need a newer one (backport).

Now I just need to figure out how to remove xorg drivers and install intel drivers...

are you sure you got that right? you DO want to run Xorg, no?

[clarkleach]

...that, and kernel versions. maybe you need a newer one (backport).

Maybe. I don't know. That's why I'm here asking questions.

are you sure you got that right? you DO want to run Xorg, no?

I'm not sure of much. That's why I'm here asking questions.

Presumably I want to run the Xorg Display Server. I'm guessing that's a different entity altogether from the actual video driver(s).
As for the kernel, is it safe (or advisable) to install the 4.8.0 kernel in this case? I don't know.

[GarryRicketson]

by clarkleach » As for the kernel, is it safe (or advisable) to install the 4.8.0 kernel in this case? I don't know.

The folks at "Kubuntu" seem to think it is safe ,

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 System:    Host: Kubuntu-ML10Gen9 Kernel: 4.8.0-51-generic x86_64 (64 bit) Desktop: KDE Plasma 5.5.5
           Distro: Ubuntu 16.04 xenial

by clarkleach » Any idea what is so different between Kubuntu and Debian/KDE?

This is another one of the differences, the folks at Ubuntu, make these changes
for the user, that way the user does not need to worry about if it is safe or not.

I don't know, so don't quote me , but there are a few others here that have done
this (adding a newer kernel to get certain "features" working), and successfully.
One thing, based on what I have read here on the forum, it is safe enough to try,
they keep the "older kernel" available, if the new one does not work , they switch back to the older one. I say "they" because I have not ever actually tried doing that my self. Perhaps some one else can go into more details.
This goes into it, to some extent : https://wiki.debian.org/HowToUpgradeKernel

[clarkleach]

I don't know, so don't quote me , but there are a few others here that have done
this (adding a newer kernel to get certain "features" working), and successfully.
One thing, based on what I have read here on the forum, it is safe enough to try,
they keep the "older kernel" available, if the new one does not work , they switch back to the older one. I say "they" because I have not ever actually tried doing that my self. Perhaps some one else can go into more details.
This goes into it, to some extent : https://wiki.debian.org/HowToUpgradeKernel

I did quote you on it Thanks for the pointer. Maybe the newer kernel is all that's required. I'll give it a try in my copious free time. What's the worst that can happen?

[ruffwoof]

Make a backup. Check you /etc/apt/sources.list file and see if contrib non-free parameters are included, or if its just main. If just main try adding those contrib and non-free parameters and run apt-get update. Fire up synaptic and have a look around for non-free using the search option and install what might seem appropriate for your hardware. If that works then after installation you can remove the contrib and non-free parameters from sources.list to be back to just using the main repositories again for subsequent updates.

It can be very cryptic for those new to Linux to associate what contrib/non-free stuff you actually need for a particular piece of hardware. In the past I've just used a process of elimination and loaded loads of firmware/drivers (stuff) before eventually pinning it down to a particular choice. The backup helps ensure that when you do you can revert to the prior good version before installing that.

If that lead nowhere, then it would suggest you might need to be running with a later kernel i.e. Debian Stable is too old. No great loss IMO if Debian doesn't fit your needs and you do opt for one of the alternatives as most other boards are a lot friendlier than around these parts IME. My guess is a lot of potential new users have been put off by a few regular debian.net forum Trolls. Some even post links to where you need to have javascript active in order to view the content (security risk).

[clarkleach]

*** UPDATE ***
I installed a new kernel from backports (4.9.0). This certainly made a difference. But there are still issues...

1. The option to select kernel 4.9.0 does not appear in the grub menu unless I enter the BIOS boot menu first and select 'debian' as my boot device. I can then select which kernel I want to boot. Does this mean I need to run grub-mkconfig?

2. I now have a desktop extended to both monitors. But not without issues. I've noticed tearing when resizing (normalizing a maximized) window. So far I've only noticed this in Chrome. Is this maybe a 'feature' of the GLX renderer or Display Server (neither one of which was upgraded with the new kernel)? The only change in the output of 'inxi -F' seems to be the 'drivers' item which I'm not sure how to interpret:

with 3.16.0-4-amd64 kernel:

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Graphics:  Card: Intel Device 191d
           Display Server: X.Org 1.16.4 drivers: fbdev,intel (unloaded: vesa)
           Resolution: 2560x1440@93.00hz
           GLX Renderer: Gallium 0.4 on llvmpipe (LLVM 3.5, 256 bits) GLX Version: 3.0 Mesa 10.3.2

with 4.9.0-0.bpo.2-amd64 kernel:

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Graphics:  Card: Intel Device 191d
           Display Server: X.Org 1.16.4 drivers: intel (unloaded: fbdev,vesa)
           Resolution: 2560x1440@59.95hz, 2560x1440@59.95hz
           GLX Renderer: Gallium 0.4 on llvmpipe (LLVM 3.5, 256 bits) GLX Version: 3.0 Mesa 10.3.2

Also there is a very small but noticeable overlap where the two screens meet, meaning the same thing appears on both monitors - a 'feature' I had noticed before on my laptop running Deb 8.2/Mate. Maybe Display Server or GLX Renderer related? Is there a prudent way to force an upgrade of the Xorg display server and change the GLX renderer to match that of Kubuntu to see if these problems goes away?

Kubuntu (4.8.0-51-generic):

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Graphics:  Card: Intel Device 191d
           Display Server: X.Org 1.18.4 drivers: (unloaded: fbdev,vesa)
           Resolution: 2560x1440@59.95hz, 2560x1440@59.95hz
           GLX Renderer: Mesa DRI Intel HD Graphics P530 (Skylake GT2) GLX Version: 3.0 Mesa 12.0.6

blah, blah, blah....