Ubuntu
xserver-xorg-video-intel package

gutsy xorg detects 1280x800, gnome thinks its 1024x768

Bug #140999 reported by lydon on 2007-09-19

This bug report is a duplicate of: Bug #131646: TVout is interfering with screen resolution on Intel graphics. Edit Remove

Affects		Status	Importance	Assigned to	Milestone
	xserver-xorg-video-intel (Ubuntu)	Invalid	Undecided	Unassigned

Bug Description

After installing gutsy on my brand new Dell XPS M1330 I found out that the intel xorg driver correctly detects the size of the integrated flat screen with 1280x800. But gnome seems to be confused and detects only 1024x768. This results in a screen that is completely available to me (can move mouse and windows over the whole 1280x800 area, but all gnome functions (panels, maximize window, etc.) only work as if the screen is 1024x768.

That means: the top panel is to short, the bottom panel floats at 768 pixels and is to short, too. maximize brings the window to 1024x768 - panels, resizing the window goes over the full physical screen.

xresprobe only sees 1024x768 (its the only mode listed in teh probes xorg.conf, so this is no big wonder). If I add 1280x800 as mode to the probe conf in /usr/share/xresprobe/xorg.conf it will detect 1280x800, but gnome is still wrong...

Using scree preferences app to change to something usefull only changes xorg.conf, gnome stays the same all the time.

Any ideas which like gremlin keeps the gnome from having fun?

Revision history for this message

lydon (ograf) wrote on 2007-09-19:

panels wrong, terminal lower right Edit (342.5 KiB, image/jpeg)

Some screenshots displaying the problem. GDM Login screen shows exactly the same behaviour.

Revision history for this message

lydon (ograf) wrote on 2007-09-19:

logs'n'stuff Edit (923.5 KiB, application/octet-stream)

Logs and infos as requested on https://help.ubuntu.com/community/DebuggingXAutoconfiguration plus some more screenshots.

Revision history for this message

Bryce Harrington (bryce) wrote on 2007-09-19:

I've seen an issue like this before when there was a second unknown display attached (like a projector) that was detected at 1024x768 or whatever. Gnome seems to get confused in that situation.

Attach the output from xrandr. My guess would be that there are multiple displays being detected, one of which is 1024x768. If this is the case, then you might be able to correct things via xrandr.

Revision history for this message

lydon (ograf) wrote on 2007-09-20:

Good hint!

ograf@vlad:~$ xrandr
Screen 0: minimum 320 x 200, current 1280 x 800, maximum 1280 x 1280
VGA disconnected (normal left inverted right)
LVDS connected 1280x800+0+0 (normal left inverted right) 287mm x 180mm
   1280x800 60.0*+ 60.0
   1280x768 60.0
   1024x768 60.0
   800x600 60.3
   640x480 59.9
TMDS-1 disconnected (normal left inverted right)
TV connected 1024x768+0+0 (normal left inverted right) 0mm x 0mm
   1024x768 30.0*
   800x600 30.0
   848x480 30.0
   640x480 30.0

As it seems there is a TV connected (can't see it anywhere...).

The command 'xrandr --output TV --off' magically heals the gnome from its size problem.

What is the best way to do this on startup? Can I add this to xorg.conf somehow? Or do I need to tweak gdm/xdm startup?

Revision history for this message

lydon (ograf) wrote on 2007-09-20:

Added to
Option "Monitor-LVDS" "LVDS"
Option "Monitor-TV" "TV"
to the Device section. The TV Monitor section has the option
Option "Enable" "false"
Screen section only uses the LVDS Monitor.

I can see in Xorg.0.log that the server reads all this, but TV stays connected on startup anyways...

Adding the xrandr call to the end of /etc/gdm/Init/Default works, but it seems hardly to be the right place to do this.