[i965gm] Kubuntu: Screen dimensions of external monitor not correct on X server startup (intel driver)

[Achim Bohnet]

Binary package hint: xserver-xorg-video-intel

External monitor (24'', 1900x1200), connected via DVI (of the docking station) to a
DellLatitude D830 (15.4'', 1680 x 1050). The laptop lid closed and BIOS set to 'prefer
docking station gfx if available.

On the external monitor I see the following bugs:

  0) after booting I see a KDM login greeter with fonts and icons way tooooo big.
       (Monitor does autoscaling). See 0th.Xorg.0.log
       I assume that the intel driver uses settings of laptop display instead the external
       monitor settings.
   1) then after login I can set with krandrtray to 1920x1200, but fonts are still too big.
       While pixel number is corrrect now , the screen dimension (in mm) used is still of
       the laptop display and from the external monitor. See 1st.Xorg.0.log, 1st.xrandr.log,
       and 1st.xdpyinfo.log

When I then login the KDM login greeter looks perfect (# of pixels and size) and after
login again and using krandrtray to switch to 1920 everything looks fine:

--- 1st.xdpyinfo.log 2007-08-29 12:05:54.000000000 +0200
+++ 2nd.xdpyinfo.log 2007-08-29 12:14:20.000000000 +0200
@@ -56,8 +56,8 @@
 number of screens: 1

 screen #0:
- dimensions: 1920x1200 pixels (331x207 millimeters)
- resolution: 147x147 dots per inch
+ dimensions: 1920x1200 pixels (519x324 millimeters)
+ resolution: 94x94 dots per inch
   depths (7): 24, 1, 4, 8, 15, 16, 32
   root window id: 0x73
   depth of root window: 24 planes

See also 2nd.Xorg.0.log, 2nd.xrandr.log and 2nd.xdpyinfo.log.

[lspci]
00:00.0 Host bridge [0600]: Intel Corporation Mobile PM965/GM965/GL960 Memory Controller Hub [8086:2a00] (rev 0c)
     Subsystem: Dell Unknown device [1028:01fe]
00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller [8086:2a02] (rev 0c) (prog-if 00 [VGA controller])
     Subsystem: Dell Unknown device [1028:01fe]

[Achim Bohnet (allee)]

xrandr output after logout/in is identical to first login.

Killing xserver show again the same bugs as after a reboot.
I have to login/out and login again to get the correct setting
for the external TFT display.

[Gabriel Ambuehl (gabriel-ambuehl)]

I *think* prefer docking station GFX is for the docking station that can hold it's own graphics card, not the output on the docking station.

BUt I do I think xrandr 1.2 is not yet entirely working as it should.

[Gabriel Ambuehl (gabriel-ambuehl)]

Also you might be able to use xrandr --output TMDS-1 --dpi to force proper dpi on the external screen (I tried it and had mixed results, it seems to only affect newly started apps or something like that). I don't think it's specific to the D830 but more of a GMA X3100 issue.

[Bryce Harrington (bryce)]

Can you please test with released Hardy 8.04.1 and/or Intrepid and see if the dpi issue is still a problem?

A lot of these dpi problems got resolved over the past year, so this may have gone away as an issue. If not, please attach a new Xorg.0.log.

[Bryce Harrington (bryce)]

Heya allee,

We're closing this bug since it is has been some time with no response from the original reporter. However, if the issue still exists please feel free to reopen with the requested information. Also, if you could, please test against the latest development version of Ubuntu, since this confirms the bug is one we may be able to pass upstream for help.

[Achim Bohnet (allee)]

Hi Bryce,

I've tried again with Kubuntu Jaunty-19-Feb-2009 and same the harware (D830 ..., Dell 24'' TFT ...) The problem is still reproduceable :( Minor change: xdpyinfo list 129 instead of 147 dpi at the beginning.

xserver-xorg-video-intel 2:2.6.1-1ubuntu2
linux-image-2.6.28-8-generic 2.6.28-8.24

dpi changes after logout/on, not when TDMS-1 is turned on and LVDS off, so TDMS is the only active monitor.
Comparing xrandr and xdpyinfo output before logout and after login:

 screen #0:
- dimensions: 1920x1200 pixels (519x324 millimeters)
- resolution: 94x94 dots per inch
+ dimensions: 1920x1200 pixels (378x236 millimeters)
+ resolution: 129x129 dots per inch

Logs attached ...

Achim

[Bryce Harrington (bryce)]

Could you please also run `lspci -vvnn > lspci-vvnn.txt` and attach that file to this bug report? Thanks ahead of time.

[Bryce Harrington (bryce)]

[This is an automatic notification.]

A new major version of the -intel driver is now available in Karmic.

This version includes a major reworking of the acceleration
architecture, which resolves a huge number of issues. We do not know
whether it resolves the issue you reported.

Would you mind testing Karmic Alpha-2 and seeing if it is still a
problem? CD ISO images are available here:

  http://cdimages.ubuntu.com/releases/karmic/

If the issue can still be reproduced on karmic, please report here with
your findings, and attach a fresh Xorg.0.log from your test, and we will
be able to forward the bug upstream.

Otherwise, if the bug no longer exists in Karmic, let us know that as
well.

In the off chance you encounter different bugs while attempting to test
Karmic, please report those as new bug reports.

[Bryce Harrington (bryce)]

We're closing this bug since it is has been some time with no response from the original reporter. However, if the issue still exists please feel free to reopen with the requested information. Also, if you could, please test against the latest development version of Ubuntu, since this confirms the bug is one we may be able to pass upstream for help.

It seems likely to me this bug is gone; the -intel driver has improved immensely in Karmic and a lot of bugs are being reported as no longer present. So hopefully that's the case here too.

[Achim Bohnet (allee)]

I had a short possibilty to borrow the D830 again. I've tried the Kubuntu Karminc beta 1 i386 LifeCDROM and the bug is still there.

After boot the latitude D830 (1680x1050) + Dell 24'' TFT via DVI of the docking station choose on first common resolution: 1152x864. So the fonts are way to big (see attachment 1-xrandr.after-login)

This part of the bug I've already seen and report with more recent hardware [GM45] Latitude E6500 + dvi in docking station + Dell 24'' TFT. https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/437173 :
[GM45] Bad resulution choice for mirror mode with two 16:10 displays

What's different from bug 437173 ss that when I turn of the LVDS, with xrandr --output LVDS --off, that the TMDS does not scale
to 1920x1600 automaticly not does xrandr --output TMDS --auto convince the driver to use the native resolution of the external TFT (that works in the GM45 case).

Achim

[7oby (tobias-hain)]

The external and internal display agree on a resolution, which both displays support. The motivation behind this algorithm for Initial Mode Selection Keith Packard explaines in this blog:
http://keithp.com/blogs/X_output_status_july_2008/

This explains your observation of the "wrong" initial mode resolution. The second observation about the DPI stems from the same I assume: The system gets the DPI of ONE of the displays and in your case it seems to be the wrong one. This has quiet some implication e.g. to Firefox font rendering.

Anyway for the second issue there's at least a workaround: KDE System Settings / Appearance / Fonts / Force DPI for Fonts. Or use some xserverrc to override the hard way.

[Achim Bohnet (allee)]

Hi 7oby,

well, ...

1) Keith describes that with the current algorigthm _his_ LVDS used the native (i.e. best) resolution. So he stopped after 'works-for-me' (perfectly fine for the first start). If this would be the case for me too, everything would be alright too ;) As this is not the case, and the algorithm fails miserably in result visible, I had to write this bug report and bug 437173.

2) I could not try you 'fix dpi' setting, as the user took the laptop with him again, nevertheless this would be a workaround (but thx for pointing me to the setting). I reported it in the hope it can be fixed. Back on topic: agreeing on one dpi is fine (in the first step) but when the high resolution monitor is turned off with xrandr, the dpi (as xrandr and xdpyinfo report them) should be changed to the native resolution of the only remaining monitor (96dpi) and not stay at 147 dpi.

Achim

[Achim Bohnet (allee)]

Off topic, but necessary: Big thx to 7oby, Bryce and all others that help to care about the intel drv, X ... I really appreciate your work!

[Bryce Harrington (bryce)]

[This is an automatic notification.]

Thanks for reporting this bug to help making the Intel graphics driver
better. We hear from upstream that a number of bugs (possibly including
this one) have been fixed in the newer DRM code from the 2.6.33 kernel.
I don't know if your bug is one of the ones fixed in this release,
though, but we've prepared a PPA with this DRM update. Would you mind
installing this, rebooting, and testing if the original issue can be
reproduced with it or not?

The DRM PPA is here:

    https://edge.launchpad.net/~apw/+archive/red

Note there could be new bugs... please file these as new reports using
the command 'ubuntu-bug linux' (for kernel or DRM or KMS bugs) or
'ubuntu-bug xorg' if you suspect them to be X.org issues.

[Bryce Harrington (bryce)]

We're closing this bug since it is has been some time with no response from the original reporter. However, if the issue still exists please feel free to reopen with the requested information. Also, if you could, please test against the latest development version of Ubuntu, since this confirms the bug is one we may be able to pass upstream for help.