Adding a second monitor

[Kevin O'Gorman]

On Fri, Jun 22, 2012 at 4:23 PM, Ric Moore <wayward4now at gmail.com> wrote:
> On 06/22/2012 11:06 AM, Kevin O'Gorman wrote:
>>
>> I've got used to using 2 monitors from using my laptop and large
>> screen to support my lectures.  It's gotten so that I like it so much
>> that I use a regular monitor with it at home, and prefer working on it
>> over using my (much more capable) desktop.
>>
>> This is silly.  I've retired, and don't really need a laptop any more.
>>  I should just add one or two extra monitors to my desktop, but I
>> tried and it failed miserably.
>> 1) the existing board had several connectors, so I tried using two of
>> them.  No joy, only one would be recognized.
>> 2) I tried a card that had been donated to a charity I work for (with
>> permission from the manager).  When I tried just putting it in without
>> an attached monitor, X would not even start.  I was in a rush, and did
>> not try it with a monitor.  It's quite possible the card is broken
>> anyway.
>> 3) I realized I'm in slightly over my head.
>>
>> So, given that I have a large PCI-E slot and a regular PCI-X slot
>> empty, I'm wondering...
>> 1) Should I expect X to manage 2 cards, and if so what should I do
>> besides just plugging them in?
>> 2) Could the problem have been missing drivers for the added card, and
>> if so how should I go about finding them?
>>
>> I tried this on 11.04, but plan to go to 12.04 soon.
>>
> What make of video card do you have?? With nVidia, it's a piece of cake as
> long as you have the nVIdia driver installed using twinview in the setup and
> write out the /etc/X11/xorg.conf file.  I have run two monitors off of one
> card long time. Nary a burp in the barrel.
>
> Now, I have two nVidia cards, that are identical, each in a PCI-E slot.
> Again, with the nVidia drivers installed, I had to select "Separate
> X-Screen" to get them both working with one monitor per card. I hope to add
> two more to get a total of 4 monitors. I'll look like a blooming stock
> exchange around here. Killing space aliens will be too KeWl.
> :) Ric


I had a total mobo failure about a year ago, and a pretty thorough
brain transplant performed on an emergency basis by a local computer
shop.  Thus, I'm unusually vague about what's inside.  I have not
installed special drivers, just whatever Ubuntu had lying around, nor
do I recall doing anything with xorg.conf,
so if I did, it was not memorable.

Here's /etc/X11/xorg.conf:
# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig:  version 270.41.06
(buildmeister at swio-display-x86-rhel47-07.nvidia.com)  Mon Apr 18
15:15:12 PDT 2011


Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0" 0 0
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
EndSection

Section "Files"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Unknown"
    HorizSync       28.0 - 33.0
    VertRefresh     43.0 - 72.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection



Here's what the kernel says:
root at treat:/proc# cat driver/nvidia/gpus/0/information
Model: 		 GeForce 8400GS
IRQ:   		 24
Video BIOS: 	 70.18.7a.00.00
Card Type: 	 PCI-E
DMA Size: 	 40 bits
DMA Mask: 	 0xffffffffff
Bus Location: 	 0000:01.00.0
root at treat:/proc#

And the gpus directory has only that one "0" subdirectory.




-- 
Kevin O'Gorman, PhD