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I'm trying to install ubuntu server 12.04 on an older desktop for a friend. The tower doesnt have an onboard graphics card, so we had to install an AGP graphics card to plug in a monitor. The install all displayed correctly, but after completing, the monitor switched to "No Signal". I was able to boot into Ubuntu initially by pressing enter on this invisible screen, and the OS seemed to display correctly.

I tried holding down SHIFT, after modifying /etc/default/grub to have a timeout, to no avail.

How can I fix this?

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up vote 2 down vote accepted

Try setting GRUB_GXMODE to 640x480x16 in /etc/default/grub: GRUB_GFXMODE=640x480x16

Next, run sudo update-grub and reboot.

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I have seen this fixed by setting console mode. If the OP has trouble with this, my method could be useful. – hexafraction Jul 23 '12 at 23:50
Awesome, I did both of these and it works perfectly now. Thanks for the help! – Nick Badal Jul 24 '12 at 18:46

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