Xfce Forum

suncat

Member

Registered: 2006-08-14

Posts: 2

GDM configuration

Hi, do not know if this is an appropriate question for the forum.
I am using Xubuntu 6.06. Radeon 7000 card using the ATI driver.
When I log out and leave my computer for a while and come back the screen is blanked and when I unblank it, the resolution has gone haywire, interference lines, objects overlaying each other, etc. I can see well enough to log in but when I get to the desktop the same thing is happening. I have to restart to clear it up.
I am running the desktop at 1024x768 (for my old eyes) and it appears that the GDM is at a higher resolution. Is there anyway to fix this.
Xfce is great, keep up the good work.
suncat
edit: following advice from another post I tried F10 at the login screen and it immediately sent the screen into another spasm.

killerbob

Member

Registered: 2005-07-30

Posts: 1

Website

Re: GDM configuration

GDM will automatically use the highest resolution that's supported by both your video card, and what it thinks your monitor is capable of. The solution is to edit your xorg.conf file to remove the higher resolutions from list of available resolutions.

Exit X. Usually you can do this by switching to Runlevel 3 by logging into a console as root, and typing "init 3".
Edit /etc/X11/xorg.conf in your favourite editor. I use nano. Look for this section:

# **********************************************************************
# Screen sections
# **********************************************************************

Section "Screen"
    Identifier  "Videoconfig"
    Device      "Videocard1"
    Monitor     "Monitor1"

   DefaultDepth 24

    Subsection "Display"
        Depth       8
        Modes "1280x1024" "1024x768" "800x600" "640x480"
    EndSubsection
    Subsection "Display"
        Depth       16
        Modes "1280x1024" "1024x768" "800x600" "640x480"
    EndSubsection
    Subsection "Display"
        Depth       24
        Modes "1280x1024" "1280x800" "1024x768" "800x600" "640x480"
    EndSubsection
    Subsection "Display"
        Depth       32
        Modes "1280x1024" "1024x768" "800x600" "640x480"
    EndSubsection
EndSection

Yours will probably look very similar to mine. Take a look at the "DefaultDepth" line at the top of the section... It says 24 in mine, meaning that I'm running at 24-bit colour depth. It also means I only need to look at the 24-bit subsection in order to change my system settings:

Subsection "Display"
        Depth       24
        Modes "1280x1024" "1280x800" "1024x768" "800x600" "640x480"
    EndSubsection

The "Modes" line is the important one. You can se that there's an extra entry in there on my system, "1280x800". That's because my laptop has a 1280x800 LCD display. (ask a stupid question ). In order to prevent your system from *ever* choosing a resolution higher than 1024x768, you just have to remove the entries for the higher resolutions. Alternatively, you can also put the "1024x768" entry first in the list. That won't disable higher resolutions, but it will tell it to try that resolution first.

EDIT: it occurs to me that I should probably tell you how to get back into X. You can try to invoke "init 4" (or "init 5" depending on your distro), or you can reboot. Either way should work.

suncat

Member

Registered: 2006-08-14

Posts: 2

Re: GDM configuration

killerbob thanks I appreciate the response, everyday you pick up some new info in this Linux journey.
suncat

timetrap

Member

Registered: 2006-09-19

Posts: 1

Re: GDM configuration

I am using OpenBSD 3.9, xorg, xfce4
I am also using the xorg Radeon Drivers

I have the exact oposite question, my xorg.conf looks like this:

DefaultDepth 24

.....

Depth        24
Modes      "1280x1024" "1024x768" "800x600" ....

Under the settings manager for resolution there are no options for "1280x1024" . . . what do I do? xfce4 works fine, I just want to use a higher resolution.

y2kprawn

Member

Registered: 2007-02-26

Posts: 1

Re: GDM configuration

I have the same problems in xbuntu. I have all the desired settings in the xorg.conf file but cannot change the screen resolution ??

bigfatgeek

Member

Registered: 2007-03-08

Posts: 1

Re: GDM configuration

I also have this issue.
I have the following line in each sub-section of my xorg.conf file:

Modes      "1280x1024" "1152x864" "1024x768" "832x624" "800x600" "720x400" "640x480"

Yet my settings app will only show up to 1152x864 resolution.
At first I just used the xrandr command to reset my screen each time I logged in. Got tired of that and just made it into a script and added it to the "Autostarted Applications" list. I know it's a work-around, but maybe someone will be gracious enough to shed some light on the real solution.

Jellybean

Member

Registered: 2007-02-17

Posts: 43

Re: GDM configuration

Why on earth does someone want different resultion in GDM and their desktop?????? Simply set the resolution setting in XFCE to "default". Then fix the resolution in GDM.

> I am running the desktop at 1024x768 (for my old eyes)
I recommend you use a high resultion but enlarge the font size. It will look better.

> Alternatively, you can also put the "1024x768" entry first in the list. That won't disable higher resolutions, but it will tell it to try that resolution first.
No, the order shouldn't matter at all. The highest possible resolution will be used.

I am using OpenBSD 3.9, xorg, xfce4
I am also using the xorg Radeon Drivers

I have the exact oposite question, my xorg.conf looks like this:

DefaultDepth 24

.....

Depth        24
Modes      "1280x1024" "1024x768" "800x600" ....

Under the settings manager for resolution there are no options for "1280x1024" . . . what do I do?

You select "default" in Xfce. If that doesn't solve it, there's something wrong in your "monitor" section.

I also have this issue.
I have the following line in each sub-section of my xorg.conf file:

Modes      "1280x1024" "1152x864" "1024x768" "832x624" "800x600" "720x400" "640x480"

Yet my settings app will only show up to 1152x864 resolution.
At first I just used the xrandr command to reset my screen each time I logged in. Got tired of that and just made it into a script and added it to the "Autostarted Applications" list. I know it's a work-around, but maybe someone will be gracious enough to shed some light on the real solution.

Again, simply select "default" to get 1280x1024.

jonespg

Member

Registered: 2007-06-17

Posts: 2

Re: GDM configuration

Howdy folks,
I am trying to get 1280x1024 set as my default screen resolution.  I have attempted the "just choose default" advice.  The options listed from Applications>Settings>Display Settings are 800x600 in various sync frequencies.  I have changed xorg.conf in various ways, based on other postings.  Right now X starts every third time when I boot.  The main problem is it doesn't go use 1280x1024.  When I took out all the other options under depth=24 it flunks.  Here's my monitor section.  Any advice?

Section "Monitor"
    Identifier    "Generic Monitor"
    Option        "DPMS"
    HorizSync    28-51
    VertRefresh    43-60
    Modeline "1280x1024_75.00" 138.54 1280 1368 1504 1728 1024 1025 1028 1069-HSync +Vsync
EndSection

Section "Screen"
    Identifier    "Default Screen"
    Device        "ATI Technologies Inc R200 BB [Radeon All in Wonder 8500DV]"
    Monitor        "Generic Monitor"
    DefaultDepth    24
    SubSection "Display"
        Depth        24
        Modes        "1280x1024" "1024x768" "800x600" "640x480"
    EndSubSection
EndSection