Ubuntu 9.04, Intel display driver problem (looks like bug 375545 is still with us)

[Chris G]

On Mon, Jul 06, 2009 at 10:46:00PM +0100, Chris G wrote:
> On Mon, Jul 06, 2009 at 08:25:06PM +0100, Chris G wrote:
> > I have just upgraded from xubuntu 8.10 to xubunto 9.04 and am having
> > big problems with Xorg.  What happens is that the Xorg Intel drivers
> > fail to detect any display, drop into failsafe mode and exit.
> > 
> > Fortunately, for some reason, Xorg also attempts to start up with vesa
> > drivers and they work OK and produce a working display on console
> > number 9 (the Intel drivers having used console 7).
> > 
> > When I boot the system I see a series of messages from the failing
> > Intel drivers saying the system is failing back into "Low Graphics
> > Mode" then a message from the Vesa driver saying that display :0 is in
> > use so that it will start up on display :1 instead.
> > 
> > It looks to me as if this is bug 375545 as the messages I see in
> > Xorg.0.log are just the same as reported in that bug report.  However
> > bug 375545 is shown as fixed by xserver-xorg-video-intel version
> > 2:2.7.1 but I have installed these drivers and still have the fault.
> > 
> > I have posted a message to bug 375545 on Launchpad but how do I
> > escalate things so it gets back to being a live bug.  I'm quite
> > prepared to believe I have done something silly but, if I have, I need
> > some help to find out what it is.
> > 
> Hmmm!  I've fixed the problem, I *suspect* it was a faulty DVI-D cable
> which meant that the Intel video drivers didn't recognise the display
> for some reason.  While Googling the problem I saw someone else had a
> similar problem with a faulty lead so I thought I'd try it.
> 
> The sequence I went through was:-
> 
>     Shut system down.
> 
>     Switch to analogue VGA (same monitor, same on-board graphics, just
>     a change of lead) and the problem went away although the quality
>     at 1600x1200 was rather poor.
> 
>     Shut system down.
> 
>     Fully turned off monitor (removed power supply connector).
> 
>     Removed analoge VGA connector, connected up a new/different DVI-D
>     connector, powered up and everything worked perfectly.  Only one X
>     process, correct Intel drivers running.  :-)
> 
> Lesson learnt, don't always assume it's a software problem and don't
> always assume that nothing else has happened to the system while doing
> an upgrade.  Presumably I (or the dog) had done something to that
> faulty DVI-D lead around the same time as I upgraded from 8.10 to 9.04.
> 
Even sillier/more confusing, the original DVI-D cable works OK as well!
Maybe it was the full reset (power on/off) of the monitor that fixed
the problem.  I'm sure I'd already plugged the 'old' DVI-D cable in
and out more than once.

-- 
Chris Green