Re: Re: How to turn off internal monitor when using external one

[Gerardo Ballabio <g.ballabio@cineca.it>]

thank you for your answer,

I've read a Xinerama Howto and I understand it's about combining
multiple monitors so that each shows a different portion of the screen.
Furthermore, if I understand correctly, every monitor is supposed to be
attached to a different graphics card.
My case is different. I have two monitors connected to the same graphics
card, and they are either supposed to show the same display, or one of
them to be on and the other one off.

Indeed, that is what happens when I am in text mode: Fn-F8 toggles
between three modes, namely, both monitors on, internal on, or external
on. But X11 ignores that completely. I've found that its behavior only
changes depending on whether the lid was open or closed *at boot time*:
if it was open, the X display is shown on both screens. If it was
closed, it's displayed only on the external monitor, but the backlight
of the internal one still turns on as soon as X starts.

I've also tried "xset dpms force off" as suggested by another poster,
but that puts *both* monitors to sleep.

I'm wondering if I should file a bug report on XFree86 about this?

Gerardo