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Linux Laptops & Projectors How-To

If you're had trouble connecting your Linux laptop to a projector at a meeting, you may find this tutorial helpful. The reason you cannot get an image from the projector is that the laptop is using a video mode that the projectoe doesn't understand so you get just a blank screen or at most a few flickers. What needs to be done is to set the laptop to a video that is compatible with the projector. You can't do this from within GNOME or KDe but must do it at the time the kernel boots by adding a video mode option. This tutorial will show you how.
First, connect the projector to the laptop while the laptop is stil off.
Then turn on the projector and make sure it;s looking at the correct input source. There may be more than one. (EX: video, Computer1, Computer2). At this point the projector will show only a blue screen,most likely, and that there is no signal coming from the input source.
Now turn on the laptop. The first thing you'll see is the BIOS loading and often the manufacturer's splash screen (Dell, Compaq, etc.). Next LILO or GRUB will start usually with a short pause to give you time to choose a kernel or add boot options, which is exactly what we want to do.
Distros like Ubuntu or Fedora make this job very easy. When the Ubuntu logo shows on the screen you'll see some options across the bottom of the screen. Pressing F4 (VGA) lets you select a different video mode. You want to choose either 600x600x16 or 1024x768x16 depending on what video mode the projector recognizes. If you guess correctly you should see the rest of the boot process (if you are in framebuffer mode). You may need to toggle between the laptop LCD and the projector using the function key on your keyboard (on my Dell, it's funxtion F8). If the screen remains blank with only a flicker or two then the video mode is too high and you need to reboot and select a lower VGA mode.
If the projector shows a blue screen and the words "No Signal" you've selected the wrong input source.If you distro doesn't have convenient selection options like the Ubuntu example then you need to add the video mode option by hand.In LILO tap the tab key and you'll see a menu of kernels available to boot. In my case they are Linux and Linux-SMP. So at the prompt I would type:
Linux-SMP vga=0x317
to boot into 1024x768x16or
Linux-SMP vga-0x314
to boot into 800x600x16. You could also edit /etc/lilo.conf to add this boot option to a new stanza. Be sure to run lilo -v after you save your changes and check for any warnings.If your distro uses GRUB as the boot loader you can type "a" to append an option at book time and like LILO you could add an entry in the GRUB menu so you can boot in "projector mode".Once you have the KDE or GNOME desktop showing on the monitor you may still need to use the resize applet to resize it down if your mouse can move off the screen.Courtesy: Dennisk from PLUG

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