From: You Can 

Linux with external Monitor

I have a Dell D500 laptop. I have installed RedHat 9.0 in a small
configuration. I have X installed and can get to the Xterm window. Now
comes the interesting part. I plan to use an external monitor plugged into
the VGA port on the Laptop. Also the native keyboard will be removed. If I
attempt to boot in this configuration nothing is on the external monitor.
With the keyboard I can use the Fn F8 key sequence to switch the video to
the external monitor. Note however this must be done before X is started or
the image is corrupted. However this only works if a keyboard is available.

I have a windows XP module that works fine in this configuration and when
windows comes up the image is directed to the external monitor and
everything works fine. My guess is that windows must execute a command to
the laptop bios that switches the video mode.

What I need is the command to control the video mode and where I can put
this command early in the linux startup so that the boot scripts are
displayed as well as the final X environment. I assume a command can be put
in the GRUB configuration file.
TIA
--
l'bodacious - Nothing is perfect between conception and death.

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