[SOLVED] Dual Monitor setup issue in Linux Mint

To preface; I have read some other threads regarding dual monitor setups and it kind of went over my head.

I am not sure if my issue is software related or hardware related

You can say that I am the original newbie- as in, not only am I new Linux, I am also new to configuration of any kind (first time in 2o years). I am learning and I apologize for my lack of knowledge and logic that you may find as you read on.

Hardware - Dell Optilex 3040 - picked it up from work before they got recycled- removed Windows from hard drive, installed latest Linux Mint via USB. Cheap HP monitors bought from Craigslist - These monitors are older but they still work- They do not have HDMI capabilities- Only VGA and DVI.

My CPU does not have VGA capability - It has a DVI and an HDMI slots.

First thing I did was to buy cables- VGA to HDMI for monitor 1 and VGA to HDMI for monitor 2. Display setting only recognizes one monitor at a time. Like if I were to unplug the DVI it would recognize the HDMI one and if I unplug the HDMI it would recognize DVI one. When both plugged together, only DVI one is recognized.

Then I bought another cable, dual VGA to one DVI - Both monitors work but they mirror each other instead of being an extension. For example if I see my browser and my mouse cursor on one screen and I would see the exact same thing on the other- Mirrored. Display setting does not give an option to extend the display versus mirroring because it does not recognize two monitors. It makes sense why it would do that.

Before I buy more cheap cables- I would like to know if there is a way to configure this in the Linux Command Line or am I out of luck and need to buy newer much more expensive monitors to have the ideal dual monitor set up. Any help in the matter would be great.

Thank you!

Dell Optiplex PCs with two motherboard ports sometimes support only one port at a time. What is the input and output from running

xrandr --listproviders

in an X terminal? Is it the same whether you use both video ports or only use the dual VGA to DVI cable?

Assuming a non-nVidia GPU, xrandr should help you configure things. With arandr as a gui for xrandr.

$ xrandr

Should list you're seen / connected displays and their resolution options.

$ xrandr --output HDMI-A-0 --mode 1920x1080 --left-of HDMI-A-1 --primary --output HDMI-A-1 --mode 1920x1080

There's also --same-as if you want to clone them. And --panning to force virtual resolutions if you're say cloning the laptop LCD and it's 1366x768 and you're using an external 1080p monitor. And --off to turn off a display, like your laptops LCD.

My usual first step when starting X.

xrandr --output HDMI-A-0 --mode 1920x1080 --panning 1920x1080+0+0 --primary \
       --output eDP      --mode 1366x768  --panning 1920x1080 --same-as HDMI-A-0
xrandr --output eDP --off

The --primary is what makes fullscreen things scale to the size of the external display, not the 1366x768 of the laptops LCD. Turning off the laptops LCD improves GPU performance. And other benefits / quirks.

Originally Posted by mrmazda Dell Optiplex PCs with two motherboard ports sometimes support only one port at a time. What is the input and output from running xrandr --listproviders in an X terminal? Is it the same whether you use both video ports or only use the dual VGA to DVI cable?

Providers: number : 1
Provider 0: id: 0x53 cap: 0x9, Source Output, Sink Offload crtcs: 2 outputs: 2 associated providers: 0 name:OLAND @ pci:0000:01:00.0

Originally Posted by Shadow_7 Assuming a non-nVidia GPU, xrandr should help you configure things. With arandr as a gui for xrandr. $ xrandr Should list you're seen / connected displays and their resolution options. $ xrandr --output HDMI-A-0 --mode 1920x1080 --left-of HDMI-A-1 --primary --output HDMI-A-1 --mode 1920x1080 There's also --same-as if you want to clone them. And --panning to force virtual resolutions if you're say cloning the laptop LCD and it's 1366x768 and you're using an external 1080p monitor. And --off to turn off a display, like your laptops LCD. My usual first step when starting X. xrandr --output HDMI-A-0 --mode 1920x1080 --panning 1920x1080+0+0 --primary \ --output eDP --mode 1366x768 --panning 1920x1080 --same-as HDMI-A-0 xrandr --output eDP --off The --primary is what makes fullscreen things scale to the size of the external display, not the 1366x768 of the laptops LCD. Turning off the laptops LCD improves GPU performance. And other benefits / quirks.

$ xrandr --output HDMI-A-0 --mode 1920x1080 --left-of HDMI-A-1 --primary --output HDMI-A-1 --mode 1920x1080
warning: output HDMI-A-0 not found; ignoring
warning: output HDMI-A-1 not found; ignoring

Originally Posted by hfadwani $ xrandr --output HDMI-A-0 --mode 1920x1080 --left-of HDMI-A-1 --primary --output HDMI-A-1 --mode 1920x1080 warning: output HDMI-A-0 not found; ignoring warning: output HDMI-A-1 not found; ignoring

Originally Posted by hfadwani To preface; I have read some other threads regarding dual monitor setups and it kind of went over my head. I am not sure if my issue is software related or hardware related You can say that I am the original newbie- as in, not only am I new Linux, I am also new to configuration of any kind (first time in 2o years). I am learning and I apologize for my lack of knowledge and logic that you may find as you read on. Hardware - Dell Optilex 3040 - picked it up from work before they got recycled- removed Windows from hard drive, installed latest Linux Mint via USB. Cheap HP monitors bought from Craigslist - These monitors are older but they still work- They do not have HDMI capabilities- Only VGA and DVI. My CPU does not have VGA capability - It has a DVI and an HDMI slots. First thing I did was to buy cables- VGA to HDMI for monitor 1 and VGA to HDMI for monitor 2. Display setting only recognizes one monitor at a time. Like if I were to unplug the DVI it would recognize the HDMI one and if I unplug the HDMI it would recognize DVI one. When both plugged together, only DVI one is recognized. Then I bought another cable, dual VGA to one DVI - Both monitors work but they mirror each other instead of being an extension. For example if I see my browser and my mouse cursor on one screen and I would see the exact same thing on the other- Mirrored. Display setting does not give an option to extend the display versus mirroring because it does not recognize two monitors. It makes sense why it would do that. Before I buy more cheap cables- I would like to know if there is a way to configure this in the Linux Command Line or am I out of luck and need to buy newer much more expensive monitors to have the ideal dual monitor set up. Any help in the matter would be great. Thank you!

I entered the lpci command to see what do I have in my cpu:

00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Host Bridge/DRAM Registers (rev 07)
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor PCIe Controller (x16) (rev 07)
00:14.0 USB controller: Intel Corporation 100 Series/C230 Series Chipset Family USB 3.0 xHCI Controller (rev 31)
00:14.2 Signal processing controller: Intel Corporation 100 Series/C230 Series Chipset Family Thermal Subsystem (rev 31)
00:16.0 Communication controller: Intel Corporation 100 Series/C230 Series Chipset Family MEI Controller #1 (rev 31)
00:17.0 SATA controller: Intel Corporation Q170/Q150/B150/H170/H110/Z170/CM236 Chipset SATA Controller [AHCI Mode] (rev 31)
00:1c.0 PCI bridge: Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #5 (rev f1)
00:1f.0 ISA bridge: Intel Corporation H110 Chipset LPC/eSPI Controller (rev 31)
00:1f.2 Memory controller: Intel Corporation 100 Series/C230 Series Chipset Family Power Management Controller (rev 31)
00:1f.3 Audio device: Intel Corporation 100 Series/C230 Series Chipset Family HD Audio Controller (rev 31)
00:1f.4 SMBus: Intel Corporation 100 Series/C230 Series Chipset Family SMBus (rev 31)
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Oland XT [Radeon HD 8670 / R7 250/350] (rev 83)
01:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Cape Verde/Pitcairn HDMI Audio [Radeon HD 7700/7800 Series]
02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 15)

Originally Posted by hfadwani [xrandr --listproviders] Providers: number : 1 Provider 0: id: 0x53 cap: 0x9, Source Output, Sink Offload crtcs: 2 outputs: 2 associated providers: 0 name:OLAND @ pci:0000:01:00.0 ... 01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Oland XT [Radeon HD 8670 / R7 250/350] (rev 83)

I have a GPU much like yours:

# xrandr --listproviders
Providers: number : 1
Provider 0: id: 0x43 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 2 outputs: 2 associated providers: 0 name:modesetting
# lspci | grep VGA
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Oland [Radeon HD 8570 / R7 240/340 OEM]
# inxi -GxxSM
System:    Host: big31 Kernel: 4.19.0-6-amd64 x86_64 bits: 64 compiler: gcc v: 8.3.0 Desktop: Trinity R14.0.7 tk: Qt 3.5.0
           wm: Twin dm: startx Distro: Debian GNU/Linux 10 (buster)
Machine:   Type: Desktop Mobo: BIOSTAR model: G31-M7 TE serial: N/A BIOS: American Megatrends v: 080014 date: 02/01/2010
Graphics:  Device-1: Advanced Micro Devices [AMD/ATI] Oland [Radeon HD 8570 / R7 240/340 OEM] vendor: Dell driver: radeon
           v: kernel bus ID: 01:00.0 chip ID: 1002:6611
           Display: server: X.Org 1.20.4 driver: modesetting alternate: ati,fbdev,vesa
           resolution: 2560x1440~60Hz, 1920x1200~60Hz
           OpenGL: renderer: AMD OLAND (DRM 2.50.0 4.19.0-6-amd64 LLVM 7.0.1) v: 4.5 Mesa 18.3.6 direct render: Yes
# cat xsetup.sh
xrandr --dpi 120 --output DP-1 --mode 2560x1440 --primary --output DVI-I-1 --mode 1920x1200 --above DP-1 # 120 DPI modeset
# xrandr | egrep 'onnect|creen|\*' | grep -v disconn | sort -r
Screen 0: minimum 320 x 200, current 2560 x 2640, maximum 16384 x 16384
DVI-I-1 connected 1920x1200+0+0 (normal left inverted right x axis y axis) 519mm x 324mm
DP-1 connected primary 2560x1440+0+1200 (normal left inverted right x axis y axis) 598mm x 336mm
   2560x1440     59.95*+  74.92
   1920x1200     59.95*+

Mine is also an AMD Oland model made by Dell. The primary relevant difference is that it has DisplayPort and DVI outputs rather than HDMI and DVI outputs. The other significant difference is you are using digital to analog adapters for your old displays, while I use no converters. Normally such adapters only represent a quality difference that may or may not be noticeable to the eye. Not everyone's eyes are equal.

To emulate Shadow_7's startup command's effect you need to substitute your GPU's connection names for Shadow_7's. Most likely the DVI output name is the same as mine, DVI-I-1. The HDMI output name is probably HDMI-1. It should be reported to you by using either 'xrandr' or 'inxi -Gxx' in an X terminal, but because your HDMI output ceases when the DVI display is connected and powered up, such reports may be incomplete. You might need to get the output name of the HDMI port when only the HDMI port is producing output. /var/log/Xorg.0.log will also report output names.

grep onnect /var/log/Xorg.0.log

will list output connector names X knows about.

I suspect your dual output failure could be due to the use of the two digital-to-VGA adapters. The only such adapter I have is a single DVI-to-VGA, and it works with my Oland.

Change the display/output names based on the output of xrandr without parms. Your names may(will) be significantly different.

$ xrandr

I think, for the sake of my sanity, I need to buy an ultra wide monitor and call it a day. Thanks everyone for your help.

I still have much to learn, the lingo, and everything is too damn new.

Thanks again!

Can you exchange those cables for a DVI cable and a HDMI-to-DVI cable? IMO based upon my experience with Oland, there's a good chance sticking to digital would avoid the failure. Digital is better in multiple ways, whether it be DVI, HDMI and/or DisplayPort.