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Author Topic: Multi monitor support  (Read 4769 times)

Offline b1ackmai1er

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Multi monitor support
« on: July 24, 2010, 10:16:05 PM »
HI,

I am interested in using TC in a signage application. Does TC support multiple monitors? i.e. can I plug in four older low power pci video cards and display output to them?

Anyone had any experience in such an application.

Thanks.

Offline b1ackmai1er

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Re: Multi monitor support
« Reply #1 on: July 24, 2010, 10:53:04 PM »
On the same subject ...

i have installed Xorg 7.5 and the graphics drivers module and restarted x windows.

How do I tell if Xorg is7.5 is running compared to Xvesa?

Thanks.

Offline Juanito

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Re: Multi monitor support
« Reply #2 on: July 24, 2010, 11:33:16 PM »
You could try:
Code: [Select]
$ ps aux | grep Xvesa
$ ps aux | grep Xorg

or look for the presence of /var/log/Xorg.0.log

Offline jur

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Re: Multi monitor support
« Reply #3 on: July 25, 2010, 12:05:20 AM »
For multi monitor support you will need to configure it in xorg.conf. I have had some success with 2 monitors. You will need to google this. Look for "multi-head" and "xinerama".

Offline b1ackmai1er

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Re: Multi monitor support
« Reply #4 on: July 25, 2010, 02:25:02 AM »
Cool. That's good news. Was that with 1 dual head video card or  2 individual video cards?

I thought xinerama was obsolete and xrandr2 does not support individual cards?

$ ps aux | grep Xorg

indicated that Xorg was running, however, I don't think I have driver support for my chipset:

Primary device is: pci 00@00:12:0
NV: Ignoring unsupported device 0x10de0533 at 00:00:12:0
everything after that refers to VESA


Offline Juanito

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Re: Multi monitor support
« Reply #5 on: July 25, 2010, 02:50:28 AM »
..however, I don't think I have driver support for my chipset:

Primary device is: pci 00@00:12:0
NV: Ignoring unsupported device 0x10de0533 at 00:00:12:0
everything after that refers to VESA

As per pci-utils (lspci), what is your chipset? Maybe you need to compile a driver?

Offline b1ackmai1er

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Re: Multi monitor support
« Reply #6 on: July 25, 2010, 03:55:25 AM »
Thanks.

Loaded the extensions

nvidia-glx
nvidia-module-2.6.33.3-tinycore

Which sped things up considerably and recognized correct resolution.

Still looking for specifics for multi-monitor multi-card setup if anyone has any experience. Thanks for all your help.

Offline jur

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Re: Multi monitor support
« Reply #7 on: July 25, 2010, 03:59:24 AM »
I don't remember the details but I came under the impression xinerama is alive and well in Xorg-7.5. See
http://www.thinkwiki.org/wiki/Xorg_RandR_1.2 as well as the xorg.conf man pages.

Offline jur

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Re: Multi monitor support
« Reply #8 on: July 25, 2010, 04:05:46 AM »
Here is my xorg.conf:

Code: [Select]
Section "ServerLayout"
        Identifier     "Xinerama Layout"
        Screen      0   "Screen0" RightOf "Screen1"
        Screen      1   "Screen1"
        InputDevice    "Mouse0" "CorePointer"
        InputDevice    "Keyboard0" "CoreKeyboard"
EndSection

Section "ServerFlags"
    Option "Xinerama" "true"
EndSection

Section "Monitor"
       Identifier   "VGA"
#       Option "Monitor-VGA1" "VGA"
#      Option "RightOf" "LVDS1"
EndSection

Section "Monitor"
        Identifier   "LVDS"
#       Option Monitor-LVDS1" "LVDS"
EndSection

Section "Device"
        Identifier  "card0"
        Driver      "intel"
        BusId       "PCI:0:2:0"
        Screen      0
EndSection

Section "Device"
       Identifier  "card1"
       Driver      "intel"
       BusId       "PCI:0:2:1"
       Screen      1
EndSection


Section "Screen"
        Identifier "Screen0"
        Device     "card0"
        Monitor    "VGA"
        DefaultDepth     24
        SubSection "Display"
                Depth     24
                Modes    "1600x900"
        EndSubSection
EndSection

Section "Screen"
       Identifier "Screen1"
       Device     "card1"
       Monitor    "LVDS"
       DefaultDepth     24
       SubSection "Display"
               Depth     24
               Modes    "1024x600"
       EndSubSection
EndSection

Section "Files"
ModulePath   "/usr/local/lib/X11/modules"
FontPath     "/usr/local/lib/X11/fonts/misc/"
FontPath     "/usr/local/lib/X11/fonts/TTF/"
FontPath     "/usr/local/lib/X11/fonts/OTF"
FontPath     "/usr/local/lib/X11/fonts/Type1/"
FontPath     "/usr/local/lib/X11/fonts/100dpi/"
FontPath     "/usr/local/lib/X11/fonts/75dpi/"
EndSection

Section "Module"
Load  "glx"
Load  "extmod"
Load  "dri2"
Load  "dri"
Load  "dbe"
EndSection

Section "InputDevice"
Identifier  "Keyboard0"
Driver      "kbd"
EndSection

Section "InputDevice"
Identifier  "Mouse0"
Driver      "mouse"
Option     "Protocol" "auto"
Option     "Device" "/dev/input/mice"
Option     "ZAxisMapping" "4 5 6 7"
EndSection

Note that this does not give me xinerama since I commented the relevant lines out. Also, some of the commented lines did not have the desired result and I did not succeed in positively tying a monitor to a device (ie card output). When I tried to force it, it resulted in black screen.

I had some problems remaining: The backbround became all garbled. I didn't pursue it further as I had no real need for it. But it definitely worked besides the background problem. And with openbox, I could make various apps prefer a screen and assign each screen to a desktop and other nice tricks.

Offline curaga

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Re: Multi monitor support
« Reply #9 on: July 25, 2010, 06:17:38 AM »
Xvesa should show a cloned desktop on all heads of the primary card; I don't know what it does with multiple cards.

With Xorg, IIRC multi-card support hasn't worked since the Xfree86 days. I'm not completely sure, but I think the best chances of things working would be four Nvidia cards, driven by the same driver.

Also, in any case you should use four cards from the same vendor anyway, to avoid headaches.
The only barriers that can stop you are the ones you create yourself.

Offline CentralWare

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Re: Multi monitor support
« Reply #10 on: September 18, 2018, 01:08:57 AM »
Anyone had any luck (in any distro, not just TC) with linux and 4+ monitors (either two ATI/AMD duals or a single Nvidia quad-head?)
NOTE: TC preferred, but this is more of an X question which I imagine is across the board.


The machine in mind is a little beefy (8x2 core AMD, 32G RAM and using a hot-swap slot in the chassis with laptop drives to select an operating system.)
With WIN7/10 the cards and LCDs are detected with default support and it's a snap setting up for a 2x2 screen pattern.  My last attempt years ago with CentOS in a similar landscape allowed screen0 to act kinda' normal, but the other three looked as though the drivers were choking (lines everywhere, text/graphics were virtually indecipherable.)


I'm guessing it's just a matter of of setting up (manually) the config file for X for card0/card1 and screen0-4 after installing ATI drivers, but if someone out there has "been there, done that" thoughts and suggestions would be very appreciated!