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I recently installed 12.04 on an HP Spectre XT ultrabook. I installed 12.04 from a USB. When the install was complete, and the computer restarted, I got a blank screen.

After some searching, I found that I had to choose "acpi=off" during the installation, which now shows up in the grub screen.

Once I was on 12.04, I upgraded to 12.10.

The issue now is that when I hit shutdown, the computer hangs on a purple shutdown screen. Usually, at this point, I press the power button on the machine to completely power off the machine.

I am new to ubuntu, and would appreciate the help. Thanks.

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I have two machines running Ubuntu. I modified my grub menu on the HP Spectre XT ultrabook to mirror my other machine.

I changed the following lines, from:






After doing this, my machine successfully shut down.

There was another problem, when the machine boots up, the LCD backlight is completely dark. I have to increase the brightness using keys on my keyboard, and I am then able to see the login screen.

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This has been happening to me every once in a while on my Toshiba Satellite L300D laptop since 12.04 and it occurred a couple of times to me after installing 12.10. On my computer it didn't happen all the time. I'd estimate about 1 in 15 shutdowns would result in an endless purple screen that required holding down the power button to force a shutdown of the computer.

It hasn't happened for a while now, however, and I think it has something to do with my recently having disabled the "speech-dispatcher" service at start-up (It always seemed like the last thing Ubuntu would try to shutdown before hanging.

I have no reason why this would have helped, but if you want to give it a try, it can't hurt anything (unless you need your computer to talk to you!)

Install Boot-up Manager (BUM)

$sudo apt-get install bum

Open boot-up manager from the dash and then uncheck the box beside "speech-dispatcher" save and quit. At the very least you will save yourself some RAM and make your boot-up and shutdown times quicker, and hopefully solve stop the shutdown from hanging (fingers crossed!)

All that said, even if it works it is just a work-around. I think this is a bug and needs to be reported.


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Thank you Matt. I found a solution just before I saw your message. Thanks again. – rahi Oct 30 '12 at 14:04

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