Intrepid. Desktop flashing on and off after login

[Derek Broughton]

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