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I've got two screens connected, one Sony TV 32" (old LCD) and one noname 17" regular PC screen. The problem is before login when it seems like the system alters between the two at boot, before login. After login in Xfce - no problem.
So I can't see the grub menu. I'm sure it's there but for that brief moment the screen is black. It's no biggie because , if needed, I can disconnect one of the screens and I'm sure I'll see the grub menu again.
What can I do with the configs, grub or whatever, before boot?
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I assume both screens will be powered on before the boot. But how are they connected (are there two motherboard sockets or is one on a GPU)? And what sort of PC is it?
There *should* be a BIOS option to say which screen to use. But that probably only applies to the BIOS output.
You could try booting the system with one screen powered off and see what happens. Then try the other. (It probably won't help but costs nothing to experiment.)
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Well this does not help you, but they are weird "two monitors" issues recently as the one "similar" to yours I experienced one month ago, not solved yet (mine is after GRUB, the two monitors goes black)
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Get black screens after grub too.
Newer Intel graphics (11-something?) seem a bit "picky" in what they display and what not. One feature is to not support BIOS boot anymore (black screen on non-efi-boot). As far as I remember, temporary using an exiisting PCIe graphics card showed boot messages.
Another thing is, when switching to a text-console, both screens showin the same content. No idea, whether this is as it should be.
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I have 2 screens, and never know which one will light first.
Has anyone tried "modeset.(module-name)=0" this may allow a lesser but more willing module to load where you might see the OS... and therefore maybe repair/hack the system.
pic from 1993, new guitar day.
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It was the old Sony TV that was grumpy. Changed to a Philips a tad newer and grub menu is visible again.
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