Hello. I have a Gentoo linux installed on a MacBook Pro.
I use Refit as first boot loader, then lilo as linux boot loader.
When i select the linux boot from refit the external monitor turns to standby. Linux boot well and only when it reaches the Xorg loading the external monitor turns on again.
If i switch to a virtual terminal with Ctrl+Alt+F1 the external monitor turns off, then switching to the X screen with Ctrl+Alt+F7 it turns on again.
I would like to be able to use the console from the external monitor, but i cannot force it to wake up.
I've tried vbetool to send a dpms signal, but it just change the main monitor state.
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the external monitor is an LG FLATRON M228WDP, connected with an adapter
"mini display -> vga"
This sounds more like a graphics driver problem than an ACPI issue.
Closing as obsolete, if this is still seen with a modern kernel please update/re-open