P1510 External Display

I spent some time finding out what combinations of internal and external displays can be used. The i810 driver calls them LFP and CRT, respectively. I'm using X.org 6.8.2. Download my xorg.conf file here. I made some different ServerLayouts, and you can choose a default one at the end of the file. The layouts are described here.

LayoutSwitch

This starts the CRT first so that we have large resolutions available for xrandr use. The CRT does not need to be connected when starting X, but the LFP is still blank. You need to use the Fn-F10 button to switch to the LFP. If you want to use a CRT with a higher resolution, first connect it, then switch to it with Fn-F10, and then use xrandr to change the resolution. Also be sure to change back to 1024x600 or smaller before switching back to the LFP, or otherwise X might crash.

Pros: Possibility of using higher resolutions on the CRT without restarting X.

Cons: Can't be used for presentations very well, because you can't see what's going on.

LayoutClone

This clones the same content to both displays. The 1024x600 mode is crunched to 800x600 on the CRT.

Pros: Good for presentations, same content on both displays.

Cons: 1024x600 is the highest resolution, you can't disable the LFP to use a higher one on the CRT.

LayoutPan

This uses Xinerama to create a 1280x1024 desktop, fully on the CRT and partially (1024x600) visible on the LFP, panning with the mouse.

Pros: Great with the CRT, and you can still see something on the LFP.

Cons: It's tedious without a CRT. Xrandr isn't available.

LayoutIndividual

This creates two individual desktops.

Pros: Both desktops work great, with xrandr and all.

Cons: You can't see the other desktop without a CRT. That wouldn't be too bad if you could move the windows to the LFP desktop, but that doesn't seem to be possible. I did find a good suggestion how it could work here. Because the input devices are shared, you can't use VNC to view the CRT desktop from the LFP one.

LayoutSpanning

This uses Xinerama to create a large spanning desktop.

Pros: You can move your windows between the displays.

Cons: Some applications aren't Xinerama aware, and create a large, partially invisible window. Xrandr isn't available. You can't see what's on the CRT from the LFP.

Remarks

What I'd like is LayoutSwitch combined with LayoutPan, so that you could change the desktop size with xrandr and if it's larger than 1024x600, the LFP would pan with the mouse. This is obviously possible with the hardware. In all of these layouts, the depth is exactly the same. It should thus be possible to have the windows exist in a buffer somewhere and have them running while changing between screen layouts. Even using Xvnc doesn't solve the problem, because you can't resize the desktop.

What I'm using

I'm now using a spanning layout so that there's a 1024x768 external display above the internal display. The resolution works with most displays and projectors I'm likely to encounter, and the width is the same on both the external and internal display, so the desktop is a rectangle.

I wrote this script to move windows from the external display down to the internal display when the external display is disconnected. It's also possible to use x11vnc and a vnc client to view the external desktop. Be sure to use the -clip and -viewonly options, otherwise strange things happen.

Last modified 2006/05/28