Results 1 to 3 of 3

Thread: Black screen on laptop's external monitor when specifying vesa driver in xorg

  1. #1
    Join Date
    Jan 2010
    Beans
    12

    Black screen on laptop's external monitor when specifying vesa driver in xorg

    Hello,

    I was wondering if anyone might be able to help me. I have an Asus z9100 laptop with an Intel 855GM integrated graphics chip, which is running Karmic (the purpose of the laptop is to be a MythTV frontend so my understanding is that it needs to run 9.x in order to connect to the MythTV 0.22 backend - I have installed and configured this using the installable Mythbuntu package) and the laptop is subject to this bug which causes random freezes:

    https://bugs.launchpad.net/ubuntu/+s...el/+bug/476817

    So, following advice for similar freezes I've seen, I have added the following options to my grub menu.lst on the kernel line:

    nolapic nomodeset

    and I have edited xorg.conf so that it makes use of the vesa driver instead of the Intel driver. This results in no freezes and if I wanted to watch Myth on the laptop screen I'd be squared away. However, the laptop has a damaged screen so the point was always to output the signal to an external monitor via its VGA out.

    When I attach the external monitor and boot with the setup as described, the external monitor is never detected. But I noticed that if I remove the "nolapic nomodeset" from the kernel boot line, it is detected. However, signal is only output to it during the earliest part of boot (when the Ubuntu logo is in the center of the screen before the full-screen graphic with the animated progress line), after which the external monitor goes black and all the display output goes to the laptop screen. The external monitor power button is still lit up green as if it has been detected and is receiving signal, but it's just a black screen.

    So, can anyone help me get the signal out to the external monitor after the initial part of the boot process, using the vesa driver? Here is the current state of my xorg.conf:

    Code:
    Section "Device"
      Identifier      "Configured Video Device"
      Driver 	  "vesa"
      
    EndSection
    
    Section "Monitor"
      Identifier      "Configured Monitor"
    EndSection
    
    Section "Screen"
      Identifier      "Default Screen"
      Monitor         "Configured Monitor"
      Device          "Configured Video Device"
    EndSection
    And here is what it used to contain, which worked perfectly on the external monitor other than the constant freezing described in the bug linked above:

    Code:
    # xorg.conf (xorg X Window System server configuration file)
    #
    # This file was generated by dexconf, the Debian X Configuration tool, using
    # values from the debconf database.
    #
    # Edit this file with caution, and see the xorg.conf manual page.
    # (Type "man xorg.conf" at the shell prompt.)
    #
    # This file is automatically updated on xserver-xorg package upgrades *only*
    # if it has not been modified since the last upgrade of the xserver-xorg
    # package.
    #
    # If you have edited this file but would like it to be automatically updated
    # again, run the following command:
    #   sudo dpkg-reconfigure -phigh xserver-xorg
    
    Section "Files"
    EndSection
    
    Section "InputDevice"
    	Identifier	"Generic Keyboard"
    	Driver		"kbd"
    	Option		"CoreKeyboard"
    	Option		"XkbRules"	"xorg"
    	Option		"XkbModel"	"pc105"
    	Option		"XkbLayout"	"us"
    EndSection
    
    Section "InputDevice"
    	Identifier	"Configured Mouse"
    	Driver		"mouse"
    	Option		"CorePointer"
    	Option		"Device"		"/dev/input/mice"
    	Option		"Protocol"		"ImPS/2"
    	Option		"ZAxisMapping"		"4 5"
    	Option		"Emulate3Buttons"	"true"
    EndSection
    
    Section "InputDevice"
    	Identifier	"Synaptics Touchpad"
    	Driver		"synaptics"
    	Option		"SendCoreEvents"	"true"
    	Option		"Device"		"/dev/psaux"
    	Option		"Protocol"		"auto-dev"
    	Option		"HorizEdgeScroll"	"0"
    EndSection
    
    Section "InputDevice"
    	Driver		"wacom"
    	Identifier	"stylus"
    	Option		"Device"	"/dev/input/wacom"
    	Option		"Type"		"stylus"
    	Option		"ForceDevice"	"ISDV4"		# Tablet PC ONLY
    EndSection
    
    Section "InputDevice"
    	Driver		"wacom"
    	Identifier	"eraser"
    	Option		"Device"	"/dev/input/wacom"
    	Option		"Type"		"eraser"
    	Option		"ForceDevice"	"ISDV4"		# Tablet PC ONLY
    EndSection
    
    Section "InputDevice"
    	Driver		"wacom"
    	Identifier	"cursor"
    	Option		"Device"	"/dev/input/wacom"
    	Option		"Type"		"cursor"
    	Option		"ForceDevice"	"ISDV4"		# Tablet PC ONLY
    EndSection
    
    Section "Device"
    	Identifier	"Intel Corporation 82852/855GM Integrated Graphics Device"
    	Driver		"intel"
    	BusID		"PCI:0:2:0"
    EndSection
    
    Section "Monitor"
    	Identifier	"S/M 770TFT"
    	Option		"DPMS"
    EndSection
    
    Section "Screen"
    	Identifier	"Default Screen"
    	Device		"Intel Corporation 82852/855GM Integrated Graphics Device"
    	Monitor		"S/M 770TFT"
    	DefaultDepth	24
    	SubSection "Display"
    		Modes		"1280x1024" "1024x768" "832x624" "800x600" "720x400" "640x480"
    	EndSubSection
    EndSection
    
    Section "ServerLayout"
    	Identifier	"Default Layout"
    	Screen		"Default Screen"
    	InputDevice	"Generic Keyboard"
    	InputDevice	"Configured Mouse"
    
    # Uncomment if you have a wacom tablet
    #	InputDevice     "stylus"	"SendCoreEvents"
    #	InputDevice     "cursor"	"SendCoreEvents"
    #	InputDevice     "eraser"	"SendCoreEvents"
    	InputDevice	"Synaptics Touchpad"
    EndSection
    Thanks for any help!
    Last edited by hallew; January 16th, 2010 at 10:45 PM.

  2. #2
    Join Date
    May 2010
    Beans
    49
    Distro
    Xubuntu 10.04 Lucid Lynx

    Re: Black screen on laptop's external monitor when specifying vesa driver in xorg

    Have you solved this yet? I am getting a blacked out screen trying to boot up Xubuntu so I am curious.

  3. #3
    Join Date
    Oct 2009
    Beans
    14

    Re: Black screen on laptop's external monitor when specifying vesa driver in xorg

    Hi, I'm afraid I can't help you but I thought there might be more interest if somebody else had the same problem. I do...

    At least it sounds like the same problem. I'm trying to display Sopcast on an external tv. It I can display the desktop, or anything else for that matter, but whenever I try to play back Sopcast on that screen it's black. Works fine on my netbook monitor though...

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •