Intrepid. Desktop flashing on and off after login

[Nigel Henry]

On Tuesday 11 November 2008 22:42, Derek Broughton wrote:
> Nigel Henry wrote:
> > You know how when you change the resolution, the desktop blacks out
> > and then returns with the new resolution, perhaps with a click of a
> > relay in the crt monitor, well I'm getting that continually, like a
> > flashing neon sign.
>
> I was getting that on my external monitor - usually interspersed with
> pop-ups from the monitor itself saying "non-preselected mode", so I'd guess
> you are trying to use a modeline the monitor doesn't like.
>
> > I do get the same sort of behaviour with other distros on this
> > machine, but is limited to one or two on and offs, then the desktop is
> > stable.
>
> That would be as it cycles through the available modes until it finds one
> that works.
>
> > When I boot Ubuntu, there are no problems as far as the GDM login
> > screen. I login, then I get 2 or 3 on and offs, with clicks from a
> > relay in the monitor, then the Gnome desktop displays ok, with no
> > further problems.
>
> So GDM is using a valid mode (I've seen people complaining that GDM/KDM
> weren't using the same screen size as their desktop, so that doesn't
> surprise me).
>
> All I can suggest is trying to find exactly the specs for the monitor are,
> and then using gtf to construct a modeline for that. --
> derek

Hi Derek. Thanks for the guidance. I borrowed the xorg.conf from Fedora 8 
that's on the same machine, and works fine. Using that one on Kubuntu 
Intrepid, the problem is resolved.

Thanks again for pointing me in the right direction.

Nigel.