I just bought a new laptop. I like to connect it to an external monitor, and configure the displays such that the laptop screen is off, and the external monitor is set to max resolution.
When I do make this change in the displays/monitors configuration, both displays go dark. After the "keep settings?" timeout expires, only the mouse cursor is visible.
The laptop is a http://zareason.com/shop/Strata-Pro-13.html. It has Intel GMA 4500MHD integrated video.
I'm using Ubuntu 11.04 (natty). This problem repros in Unity and GNOME Shell. Repros with both VGA and HDMI outputs. Does not repro in Ubuntu 10.04.2, so it makes me suspect some kernel problem in Ubuntu 11.04.
Update (Mon Jun 20 02:19:33 UTC 2011):
- Kernel is 2.6.38-8-generic-pae (32-bit). Problem also repros on non-PAE 32-bit kernel.
- lsmod shows the "i915" driver is loaded and "video" is using it, so I'm guessing the video driver in use is "i915".
- I filed a bug in launchpad, too: https://bugs.launchpad.net/unity/+bug/799609
Upgrading my Linux kernel to 2.6.39 fixed the problem.
I describe an easy way to do this in Wireless on an Atheros AR9285 is slow and disconnects (another issue I had with the kernel that came with Natty).