Laptop screen blank when using second monitor

[David G. Miller]

Oliver Ruebenacker <curoli <at> gmail.com> writes:


>      Hello,
>   Until this morning, my Lenovo Thinkpad T430 running KDE on Fedora 19 
was working fine sitting on a base with a second monitor attached. I 
removed it from the base and connected another second monitor (a 
projector) and things were still fine. When I put it back into the base, 
the laptop screen went blank, and it was using only the second screen. 
When I remove it from the base, it uses the built-in screen, but as soon 
as I put it into the base, it only uses the second screen. Interestingly, 
when I restart, it uses both screens properly until after I log in.
>   Any advice? Thanks!
> 
<SNIP>
I had an HP laptop that decided that the brightness of the built-in 
display should be set to zero when an external monitor was attached.  
Doesn't sound like the same thing because of the different behavior 
between KDE and Gnome.  You might try hitting the hardware brightness "up" 
button a few times just to see though.

Cheers,
Dave