Second monitor not showing proper resolution

[keegan]

HI all,

It seems that whenever I boot my laptop (hp probook 6450b) without a monitor attached, then boot with a monitor later attached, the configuration gets all messed up.

Currently, if I boot with the monitor attached, right after the blue loading screen (at the login prompt) i get two black monitors and a mouse, with no login screen. Unplugging the monitor shows the login screen on the laptop.

If i boot without the monitor attached, log in, then plug it in, i see the following from xrandr:

Screen 0: minimum 320 x 200, current 2390 x 768, maximum 8192 x 8192
LVDS1 connected 1366x768+0+0 (normal left inverted right x axis y axis) 310mm x 174mm
   1366x768       59.6*+
   1024x768       60.0  
   800x600        60.3     56.2  
   640x480        59.9  
VGA1 connected 1024x768+1366+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768       60.0* 
   800x600        60.3     56.2  
   848x480        60.0  
   640x480        59.9
HDMI1 disconnected (normal left inverted right x axis y axis)
DP1 disconnected (normal left inverted right x axis y axis)
HDMI2 disconnected (normal left inverted right x axis y axis)
HDMI3 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)
DP3 disconnected (normal left inverted right x axis y axis)

The problem is that before i booted once without it connected, I could get it to display at 1280x1024.

I had this problem once before, and took the following steps to resolve it:

[08:51 AM][keegan@localhost:~]#>cvt -v 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
[08:51 AM][keegan@localhost:~]#>xrandr --newmode "1280x1024_60.00" 109.00 1280 1368 1496 1712 1024 1027 1034 1063 -hsync +vsync

Now doing xrandr shows the new modes at the bottom:

[08:52 AM][keegan@localhost:~]#>xrandr
Screen 0: minimum 320 x 200, current 2390 x 768, maximum 8192 x 8192
LVDS1 connected 1366x768+1024+0 (normal left inverted right x axis y axis) 310mm x 174mm
   1366x768       59.6*+
   1024x768       60.0  
   800x600        60.3     56.2  
   640x480        59.9  
VGA1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768       60.0* 
   800x600        60.3     56.2  
   848x480        60.0  
   640x480        59.9  
HDMI1 disconnected (normal left inverted right x axis y axis)
DP1 disconnected (normal left inverted right x axis y axis)
HDMI2 disconnected (normal left inverted right x axis y axis)
HDMI3 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)
DP3 disconnected (normal left inverted right x axis y axis)
  1280x1024_60.00 (0xc4)  109.0MHz
        h: width  1280 start 1368 end 1496 total 1712 skew    0 clock   63.7KHz
        v: height 1024 start 1027 end 1034 total 1063           clock   59.9Hz

And doing the following fixes it:

[09:01 AM][keegan@localhost:~]#>xrandr --addmode VGA1 1280x1024_60.00
[09:01 AM][keegan@localhost:~]#>xrandr --output VGA1 --mode 1280x1024_60.00 --auto --left-of LVDS1

However, now when I reboot, all settings are lost, and if the monitor is attached, i get the black screen with a mouse at login.


I did notice that when I shutdown, it hangs on "Running guests on default URI", and i get a stack trace. It will keep dumping stack traces, and i have to hold down the power button to force it off.



If anyone has any suggestions, I appreciate it. Again, all of this worked until i booted without the attached monitor. There is no options in the Monitors preferences dialog.

[TomasM]

Hi Keegan. It sounds like there's a bug in your graphics driver, or a problem with your monitor's EDID. Can you borrow another laptop to check it out?

Anything you do with xrandr won't be 'saved', and has to be run every time. If you're always using the same monitor, have you tried adding these settings to an xorg.conf file? Try something like this:

Section "Screen"
        Identifier "Screen0"
        Monitor "VGA1"
EndSection

Section "Monitor"
        Identifier   "VGA1"
        Modeline "1280x1024_60.00"  109.00  1280 1368 1496 1712  1024 1027 1034 1063 -hsync +vsync
        Option "PreferredMode" "1280x1024_60.00"
EndSection

and add/save it to /etc/X11/xorg.conf, or a new file in /etc/X11/xorg.conf.d/ .

[TomasM]

Sorry, the sample xorg.conf file I originally posted was wrong. I just came across a monitor with a similar problem (thanks for letting me know about cvt!), and realised I'd made a mistake...the above should work fine now.