Screen stopped blanking

[Matthew Saltzman]

On Thu, 2012-10-04 at 09:03 -0400, Kevin H. Hobbs wrote: 
> I'm having a similar problem but with one monitor on a dual monitor
> workstation:
> 
> http://lists.fedoraproject.org/pipermail/users/2012-August/423737.html
> 
> > I have a Dell Latitude E6410 with an nVidia graphics card, using the
> > nouveau driver and the GNOME desktop on F17.
> 
> I also use the nouveau driver but with KDE on F17
> 
> > 
> > Recently, the laptop screen stopped blanking when idle in X mode.
> 
> Mine never blanked in F17 but blanking worked in previous fedora
> releases. Do you know _how_ recently it stopped blanking?

A week or so ago, but I'm not sure exactly what I might have installed
or updated to cause it.  There are recent kernels, but no recent nouveau
driver.

> 
>   I've
> > modified the screen-blank settings, to no avail.
> 
> Same here.
> 
>   If I switch to a
> > virtual console, blanking works fine. 
> 
> Hmm, I get the same behavior in a virtual console as I do in X, that is
> on monitor suspended one remains on. Maybe our problems are different.
> 
> > Any hints what might have changed or what I might look for to get it
> > working again?
> 
> What happens when you do :
> 
> xset dpms force off

Works a treat.

No, wait.  It worked the first time, then the next couple of times the
screen flashed off and on.  Then it worked fine again.  (Actually,
there's a very slight ghost image.)

Meanwhile, when the unit is docked, the external screen blanks, but then
I can't get it to come back on.  If I switch to a VC, the external
screen remains blank.  If I undock the machine, the built-in screen
remains dark in X and in VC.

> 
> When I do it my monitors appear to shut down but then one turns back on.
> 
> 

Just for grins, I tried to install the presentation-mode extension to
see if it offered a setting to change, but the new menu option doesn't
show up.  This seems to be par for the course with extensions.  The hot
right corner extension doesn't work and the weather app doesn't show up.
There's apparently been no progress on porting those extensions to
recent versions of gnome-shell.

-- 
Matthew Saltzman
Clemson University Math Sciences
mjs AT clemson DOT edu