Redhat Dual Widescreen Problems

yogomix · 05-12-2008, 10:23 AM

Hello,

I am trying to install two widescreen monitors as a dual display, however I cannot get both monitors to operate at full resolution. Either one can be at full resolution, and the other lowered; or both can operate at a lowered resolution. Any advice would be appreciated, althought I've looked through a good number of articles.

The tech details:

OS: Red Hat Enterprise Linux WS release 4 (Nahant Update 5)
Monitors: Samsung SyncMaster 204bw - 19" widescreen
Graphics card: nVidia NV44 Quadro NVS285
Desired resolution: 1680x1050 on both monitors

Below you will find my xorg.conf

Code:

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings:  version 1.0  (buildmeister@builder26)  Thu Dec 13 18:56:19 PST 2007

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

Section "Files"
    RgbPath         "/usr/X11R6/lib/X11/rgb"
    FontPath        "unix/:7100"
EndSection

Section "Module"
    Load           "dbe"
    Load           "extmod"
    Load           "type1"
    Load           "freetype"
    Load           "glx"
EndSection

Section "ServerFlags"
    Option         "Xinerama" "0"
EndSection

Section "InputDevice"
    # generated from data in "/etc/sysconfig/mouse"
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "IMPS/2"
    Option         "Device" "/dev/input/mice"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
    # generated from data in "/etc/sysconfig/keyboard"
    Identifier     "Keyboard0"
    Driver         "kbd"
    Option         "XkbLayout" "gb"
    Option         "XkbModel" "pc105"
EndSection

Section "Monitor"
    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Samsung SyncMaster"
    HorizSync       30.0 - 81.0
    VertRefresh     56.0 - 75.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Videocard0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "Quadro NVS 285"
    Option         "CustomEDID" "CRT-1 /tmp/edid.bin"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Videocard0"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "TwinView" "1"
    Option         "TwinViewXineramaInfoOrder" "CRT-0"
    Option         "metamodes" "CRT-0: 1680x1050 +0+0, CRT-1: 1400x1050 +1680+0"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

It would be boss to get this sorted. But any pointers will help.

TIA,
Yog

GrapefruiTgirl · 05-12-2008, 10:36 AM

Not 100% certain, but it may help to define the second video card port, similar to how you defined the first one.
Also, Do the same for the second monitor (you have only defined one monitor there).

The xorg.conf man page, as well as the nVIdia Readme file included with your driver or downloadable/viewable on the nVidia website, provide all the valuable info you should need to make that work.

That'll make a nice display

with those two monitors.

If you run into further trouble, post us some more details. Also, if it would help, I'll post my xorg.conf for you to see as an example; I have currently 3 monitors set up (will be 4 if/when I can afford a 4th).

Sasha

yogomix · 06-17-2008, 03:29 AM

Thanks for the help, but sorry it's taken ages to get back to you.

I updated the xorg.conf like this with the extra line for another video card. Now the resolution looks ok, but there is a black line down the left-hand side of the right-hand monitor! How do I fix this?

Code:

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

Section "Files"
    RgbPath         "/usr/X11R6/lib/X11/rgb"
    FontPath        "unix/:7100"
EndSection

Section "Module"
    Load           "dbe"
    Load           "extmod"
    Load           "type1"
    Load           "freetype"
    Load           "glx"
EndSection

Section "ServerFlags"
    Option         "Xinerama" "0"
EndSection

Section "InputDevice"
    # generated from data in "/etc/sysconfig/mouse"
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "IMPS/2"
    Option         "Device" "/dev/input/mice"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
    # generated from data in "/etc/sysconfig/keyboard"
    Identifier     "Keyboard0"
    Driver         "kbd"
    Option         "XkbLayout" "gb"
    Option         "XkbModel" "pc105"
EndSection

Section "Monitor"
    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Samsung SyncMaster"
    HorizSync       30.0 - 81.0
    VertRefresh     56.0 - 75.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Videocard0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "Quadro NVS 285"
    Option         "CustomEDID" "CRT-1 /tmp/edid.bin"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Videocard0"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "TwinView" "1"
    Option         "TwinViewXineramaInfoOrder" "CRT-0"
    Option         "metamodes" "CRT-0: 1680x1050 +0+0, CRT-1: 1400x1050 +1680+0"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Device"
    Identifier     "Videocard0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "Quadro NVS 285"
    Option         "CustomEDID" "CRT-1 /tmp/edid.bin"
EndSection

I tried changing the

Code:

Option         "metamodes" "CRT-0: 1680x1050 +0+0, CRT-1: 1400x1050 +1680+0"

line but this didn't fix anything. Does the fact I'm using CRT instead of DFP (it's LCD screen I have) effect anything?

Thank you again... one day I'll love xorg.confs!

Yog

GrapefruiTgirl · 06-17-2008, 02:09 PM

There are provisions in the configuration for specifying either CRT, DFP, or TV, and while I am not sure what effect they have on the X server or the driver, it would probably be best if you specify DFP instead of CRT.

Also, you can use the line:

Code:

Option "ConnectedMonitor" "DFP, DFP"

in your SCREEN section to be sure the driver realizes that it is a DFP (or LCD).

Try that and see if there is any difference. Then we shall see about the black line you describe; can you tell if it is actually a "line" of some kind, or might it be that the left edge of the screen (or the whole image) is shifted to the right, leaving a black area??

Cheers!

Sasha

yogomix · 06-18-2008, 11:27 AM

Hi,

Thanks again.

The "black line" I speak of is basically meaning that there is a bit of screen that should display stuff, but it appears as if everything is shifted over to the right.

HTH
Yog

GrapefruiTgirl · 06-18-2008, 03:54 PM

It may just be that you need to adjust the positioning of the display using the monitor controls (is that even possible with a DFP?? I don't know) but I recall back when I was switching back & forth from Win to Linux while tossing Win, I found that my display acted differently in Win than it did in Linux. Each time I rebooted to the other, I would need to use the monitor controls to center and resize the image.. Driver differences I guess. when it was perfect in Linux, Win would show it moved off one edge of the screen, and too small overall.

Not sure if you are experiencing something like this, but if not, then browse the readme for the driver (either from nvidia.com or by extracting the driver archive with "--extract-only" )and grab the readme file out of it. There are loads of other options you may find help you out.

Good luck

Sasha