I'm not sure if this is the right forum to post to. I am running kubuntu 10.10/KDE SC 4.6 on a Thinkpad T400 with Intel graphics (GMA 4500). The laptop has a 1200x800 LCD and I have attached an external LCD with 1680x1024.

I initially configured my desktop with the external monitor attached. I run an extended virtual desktop spanning both monitors. There is a single panel on the laptop monitor only. There are different wallpapers on each monitor and each monitor is set to show different subsets of the files in /home/[user]/Desktop folder.

When I boot the machine without the external monitor, KDE is unusable. Instead of displaying only what is set for the internal monitor, it appears that the external monitor content is rendered on top of the internal monitor content. Only the files that display on the external screen are visible and the panel is hidden. Any windows that I open can't be accessed because they open on the internal monitor.

I get the same behavior if I boot with the external monitor attached and then use xrandr to turn off the external monitor and display everything on the laptop monitor.

I don't believe this is a problem with X or xorg.conf, since LXDE behaves normally, showing only a small screen on the single monitor or a large screen when the external monitor is detected. Also editing xorg.conf doesn't fix anything.

The only solution I see is to use a cloned display or switch to another display manager.

HELP! What has to be done to have different content on two monitors when attached and only the content of the internal monitor when the external monitor is not attached?

Paul

Solved the problem...

Needed to set the laptop monitor as "primary". Apparently it isn't done by default?!?