Can't get maximum resolution from monitor

English Hardware
#1

opensuse 13.2 32bit KDE 4.14.9
Video card - Asus Extreme AX300/TD capable of 2048x1536
Monitor - Acer AL-1716 capable of 1280 x 1024 at 75 Hz

KDE Configure Desktop > Display and Monitor > Display Configuration shows a maximum available of 1024 x 768.

Xrandr reports

:~> xrandr
Screen 0: minimum 320 x 200, current 1024 x 768, maximum 4096 x 4096
VGA-0 connected primary 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768      60.00* 
   800x600       60.32    56.25  
   848x480       60.00  
   640x480       59.94  
DVI-0 disconnected (normal left inverted right x axis y axis)
S-video disconnected (normal left inverted right x axis y axis)

/etc/X11/xorg.conf.d/50-monitor.conf is empty. I tried adding a mode line from the output of cvt. No change, I even connected the DVI socket via a DVI - VGA cable. No change.

Anu suggestions?

#2

Maybe the monitor is not taking to the system. Is there by chance a KVM switch in the mix. That can block handshakes.

You may have to add the additional monitor res by hand in etc/X11/xorg.conf or one of the xorg.cong.d files. You firs have to generate a model line to use


cvt 1280 1024

This gives the modeline string for that res

in either the xorg.conf or the xorg.conf.d/50-monitor.conf

put something like this


Section "Monitor"

    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "CRT-1"
    HorizSync       55.0 - 83.0
    VertRefresh     50.0 - 75.0
    ModeLine       "1600x900_60.00" 119.00 1600 1696 1864 2128 900 901 904 932 -hsync +vsync
EndSection

Using the modeline string you generated

That should give you the option in you desktop settings screen

#3

No KVM switch. I had already done what you have suggested as indicated in my post, but just to make sure I repeated the process like this…

# cvt 1280 1024
# 1280x1024 59.89 Hz (CVT 1.31M4) hsync: 63.67 kHz; pclk: 109.00 MHz
Modeline "1280x1024_60.00"  109.00  1280 1368 1496 1712  1024 1027 1034 1063 -hsync +vsync

and added it to your post using jstar in the “no word wrap mode” so that /etc/X11/xorg.conf.d/50-monitor.conf reads like this now…

# cat /etc/X11/xorg.conf.d/50-monitor.conf
# Having multiple "Monitor" sections is known to be problematic. Make
# sure you don't have in use another one laying around e.g. in another
# xorg.conf.d file or even a generic xorg.conf file. More details can
# be found in https://bugs.freedesktop.org/show_bug.cgi?id=32430.
#
#Section "Monitor"
#  Identifier "Default Monitor"
#
#  ## If your monitor doesn't support DDC you may override the
#  ## defaults here
#  #HorizSync 28-85
#  #VertRefresh 50-100
#
#  ## Add your mode lines here, use e.g the cvt tool
#
#EndSection

Section "Monitor"

    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "CRT-1"
    HorizSync       55.0 - 83.0
    VertRefresh     50.0 - 75.0
    ModeLine       "1280x1024_60.00"  109.00  1280 1368 1496 1712  1024 1027 1034 1063 -hsync +vsync
EndSection

It made no difference.

#4

Can you please post your /var/log/Xorg.0.log?

Also, to have the settings in 50-monitor.conf applied, you also need a 50-screen.conf (or similar, the exact names don’t matter) that actually refers to your 50-monitor.conf. Something like this should suffice in your case:

Section "Screen"
  Identifier "Default Screen"
  Device "Default Device"
  Monitor "Monitor0"
EndSection
#5

That, I did NOT know. And your advice solved the problem. Thanks to both of you I now have this post to refer to the next time a friend brings an old box that can’t run the latest Windows.

#6

One small discrepancy. The above works just fine when I use a VGA - VGA cable but when I connect with a DVI (computer) to VGA (monitor) cable the resolution drops back to the lower setting. Do the /etc/X11/xorg.conf.d/50-screen.conf and /etc/X11/xorg.conf.d/50-monitor.conf need modification for a DVI monitor? The SDB:Configuring graphics cards - openSUSE page only had instructions for 11.3 using /etc/xorg.conf.

Or might it be the cable itself that’s the problem?

#7

I have no experience with DVI cables, but according to this you would need a 50-device.conf as well (with more than just comments):
https://forums.opensuse.org/showthread.php/500364-Horrible-graphics-on-new-install?p=2660566#post2660566
Something like this might suffice (exchange the driver with the correct one):

Section "Device"
  Identifier "Default Device"
  Driver "radeon"
EndSection

You could also assign the monitor sections to the actual outputs there, like:

  Option "monitor-DVI-0" "Monitor0"

(see the comments in the original file)

Or might it be the cable itself that’s the problem?

I wouldn’t think so.
But the question is still why the resolution is not detected correctly in the first place?
Xorg.0.log should tell.
Are you maybe using some generic driver (fbdev)?

#8

I’m using the radeon driver. Here are the config files at present…

50-device.conf

Section "Device"
 Identifier "Default Device"
 Driver "radeon"
 Option "monitor-DVI-0" "Default Monitor"
EndSection

50-screen.conf

Section "Screen"
  Identifier "Default Screen"
  Device "Default Device"
  Monitor "monitor-DVI-0"
EndSection

50-monitor.conf

Section "Monitor"

    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "CRT-1"
    HorizSync       55.0 - 83.0
    VertRefresh     50.0 - 75.0
    ModeLine       "1280x1024_60.00"  109.00  1280 1368 1496 1712  1024 1027 1034 1063 -hsync +vsync
EndSection

And here is my Xorg.0.log…


    30.661] (==) Using config directory: "/etc/X11/xorg.conf.d"
    30.661] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
    30.662] (==) No Layout section.  Using the first Screen section.
    30.662] (**) |-->Screen "Default Screen" (0)
    30.662] (**) |   |-->Monitor "<default monitor>"
    30.662] (**) |   |-->Device "Default Device"
    30.662] (==) No monitor specified for screen "Default Screen".
    Using a default monitor configuration.

    30.701] (II) RADEON(0): Output VGA-0 has no monitor section
    30.827] (II) RADEON(0): Output DVI-0 has no monitor section
    30.827] (II) RADEON(0): Output S-video has no monitor section
    30.833] (II) RADEON(0): EDID for output VGA-0
    30.958] (II) RADEON(0): EDID for output DVI-0
    30.959] (II) RADEON(0): Printing probed modes for output DVI-0
    30.959] (II) RADEON(0): Modeline "1024x768"x60.0   65.00  1024 1048 1184 1344  768 771 777 806 -hsync -vsync (48.4 kHz e)
    30.959] (II) RADEON(0): Modeline "800x600"x60.3   40.00  800 840 968 1056  600 601 605 628 +hsync +vsync (37.9 kHz e)
    30.959] (II) RADEON(0): Modeline "800x600"x56.2   36.00  800 824 896 1024  600 601 603 625 +hsync +vsync (35.2 kHz e)
    30.959] (II) RADEON(0): Modeline "848x480"x60.0   33.75  848 864 976 1088  480 486 494 517 +hsync +vsync (31.0 kHz e)
    30.959] (II) RADEON(0): Modeline "640x480"x59.9   25.18  640 656 752 800  480 489 492 525 -hsync -vsync (31.5 kHz e)
    30.959] (II) RADEON(0): EDID for output S-video
    30.959] (II) RADEON(0): Output VGA-0 disconnected
    30.959] (II) RADEON(0): Output DVI-0 connected
    30.959] (II) RADEON(0): Output S-video disconnected
    30.959] (II) RADEON(0): Using exact sizes for initial modes
    30.959] (II) RADEON(0): Output DVI-0 using initial mode 1024x768

I tried changing the identifier in 50-monitor.conf to “monitor-DVI-0” but that made no difference. Still, the log reports “Output DVI-0 has no monitor section”.

I must be doing something obviously wrong but I don’t see it. Thanks for all the work you’ve put into this.

#9

Your monitor section is called “Monitor0”, so you have to specify “Monitor0” here, not “Default Monitor”.

50-screen.conf

Section "Screen"
  Identifier "Default Screen"
  Device "Default Device"
  Monitor "monitor-DVI-0"
EndSection

Same here.
It should still be “Monitor0”.

And here is my Xorg.0.log…

So apparently your monitor seems to report a maximum resolution of 1024x768.

#10

Changes made. Problem is solved. Thanks again.