since i installed ubuntu on my Medion Akoya E7214 i have funny problems. It took some time to realize this. With standard settings my computer woke up every midnight. That annoyed a lot. So i searched and found, that acpi is the problem. I tryed to boot with option acpi=off (in /boot/grub/grub.cfg in the kernel-statement of the menu). But now the shutdown isn't working well. I have to switch power off manually and it seems to shut down much more slowly. Now i tryed acpi=noirq and i had no keyboard anymore. Fortunadly i had an external keyboard to make changes back. Now i changed it to acpi=off again. But this isn't what i really want. Can anyone give me a clue how to deactivate this wakeup on midnight without deactivating whole acpi? This seems to be a bug somewhere.
Disabing ACPI should be a last resort, in case you've almost given up. Check your BIOS settings whether you have a scheduled wakeup, it's called Resume by Alarm on AWARD BIOSes.