Installing Ubuntu on HP Elitebook 6930p

Finally Ubuntu is working well on my new HP Elitebook 6930p. First it froze immediately after starting up. Booting with kernel options acpi=off solved that, but linux would still complain about the BIOS and stuff like suspending, watching how much charge your batteries have etc. did of course not work. Luckily the Linux Laptop Wiki provided the answer in one of the comments. You simply need to turn off the option “Fan always on when on AC power” in the BIOS. In that case you don’t have to disable ACPI and linux is also not complaining about that the BIOS is not compatible. Very weird