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Whenever I have a dual monitor setup on my Laptop, one screen is the laptop display and the other the external monitor, I get into trouble with the X server framebuffers.

Often the larger of the two displays, which is the external monitor, is not fully covered. Even when I disable the laptop display the height of the external display is till limited to the same height as the laptop display. No matter how I rearrange the two screens in gnome-display-properties.

So basically, where do I start my fault diagnose? Is it gnome, X-server, display-drivers? Which CLI tools should I use to verify that all parts of the display system has the same geometry?

Also, another frequent problem is that the laptop LCD is often black when resumed from suspended state. I can see that the LCD is active by a faint image of the login window, but the LCD backlit is off. If it is not black, very often the LCD display driver is incorrectly resumed since I get picture disturbances (flickering random pixeldata in various areas) as well as H/V flickering shifts.

I've had these problems a lot in Ubuntu 10.04 LTS but I have recently upgraded to 11.04 LTS since all my googling ended up in discussions around problems in 10.10 and solutions in 11.04.


Similar problem as in this question and this question

Seems like xrandr is the way to go, I'll dig in to that tool more later today. Maybe I should withdraw my bounty and use the rep's to get access to the chatroom instead...

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up vote 1 down vote accepted

It seems like

$ unity --reset &

Solves the problem, there is probably a synchronisation issue between the display setup and the window manager.

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