/etc/X11/xorg.conf won't change the resolution.

stf92 · 07-14-2012, 06:24 PM

Hi:
I reinstalled my linux distribution after having lost the partition. As I always do, I modified /etc/X11/xorg.conf leaving the only screen section as follows:

Code:

# **********************************************************************
# Graphics device section
# **********************************************************************

# Any number of graphics device sections may be present

Section "Device"
    Identifier  "VESA Framebuffer"
    Driver      "sis"
    #VideoRam    4096
    # Insert Clocks lines here if appropriate
EndSection

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

# Any number of screen sections may be present.  Each describes
# the configuration of a single screen.  A single specific screen section
# may be specified from the X server command line with the "-screen"
# option.
Section "Screen"
    Identifier  "Screen 1"
    Device      "VESA Framebuffer"
    Monitor     "My Monitor"

# If your card can handle it, a higher default color depth (like 24 or 32)
# is highly recommended.

#   DefaultDepth 8
   DefaultDepth 16
#   DefaultDepth 24
#   DefaultDepth 32

# "1024x768" is also a conservative usable default resolution.  If you
# have a better monitor, feel free to try resolutions such as
# "1152x864", "1280x1024", "1600x1200", and "1800x1400" (or whatever your
# card/monitor can produce)

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

EndSection

As you can see, the entry for Depth 16 has all three modes set to 800x600. When X starts, it says he is using /etc/X11/xorg.conf. However, the resolution doesn't change. In /var/log/Xorg.0.log I find:

Code:

(II) Open ACPI successful (/var/run/acpid.socket)
(II) AIGLX: Resuming AIGLX clients after VT switch
(II) SIS(0): Setting custom mode 800x600 on CRT1
(II) SIS(0): Setting custom mode 800x600 on CRT2
(II) Mouse1: ps2EnableDataReporting: succeeded
(II) AIGLX: Suspending AIGLX clients for VT switch
(II) SIS(0): Restoring by setting old mode 0x03
.................................................[the periods are mine]
..................................................
..................................................
(II) Open ACPI successful (/var/run/acpid.socket)
(II) AIGLX: Resuming AIGLX clients after VT switch
(II) SIS(0): Setting custom mode 800x600 on CRT1
(II) SIS(0): Setting custom mode 800x600 on CRT2
(II) Mouse1: ps2EnableDataReporting: succeeded
(II) AIGLX: Suspending AIGLX clients for VT switch
(II) SIS(0): Restoring by setting old mode 0x03

The same block of seven lines repeats itself many times. I think the line
(II) SIS(0): Restoring by setting old mode 0x03

has something to do with this problem. The question is: why does the resolution not change?

r0h1t · 07-15-2012, 12:28 AM

Xserver is doing what its told - set the resolution to 800x600 as you've mentioned in your xorg.conf file. I fail to see the problem here.

stf92 · 07-15-2012, 01:07 AM

You're right. The resolution is set to 800x600. But with this resolution I always saw a screen larger than the physical screen (virtual screen panning). I used the mouse to access those parts of the desktop outside the physical screen. But this happens no more.

stf92 · 07-15-2012, 01:23 AM

I don't believe it. With this Screen section I do get virtual screen panning!:

Code:

Section "Screen"
    Identifier  "Screen 1"
    Device      "VESA Framebuffer"
    Monitor     "My Monitor"

# If your card can handle it, a higher default color depth (like 24 or 32)
# is highly recommended.

#   DefaultDepth 8
   DefaultDepth 16
#   DefaultDepth 24
#   DefaultDepth 32

# "1024x768" is also a conservative usable default resolution.  If you
# have a better monitor, feel free to try resolutions such as
# "1152x864", "1280x1024", "1600x1200", and "1800x1400" (or whatever your
# card/monitor can produce)

####        Modes en el archivo original: "640x480" "1024x768" "800x600" 
# Ultima configuracion en vigor:
#   "800x600" como 1er campo de lineas Modes (el unico al que KDE 
#   o quien sea que sea parece dar bola). 
#           "1024x768" era el 1er campo en los 4 Modes!
    Subsection "Display"
        Depth       8
        Modes "640x480" "1024x768" "800x600" 
    EndSubsection
    Subsection "Display"
        Depth       16
        Modes "800x600" "1024x768" "800x600" 
    EndSubsection
    Subsection "Display"
        Depth       24
        Modes "800x600"
    EndSubsection
    Subsection "Display"
        Depth       32
        Modes "640x480" "1024x768" "800x600" 
###########             Modes "640x480"
    EndSubsection

EndSection

I do not understand where the difference is. There are some changes but why do they determine virtual screen panning?