@Thomas Lenarz: Hmm.. So there seems to be some improvement with the 3.4 kernel, but no final fix. In the meantime, RC4 is out, maybe you want to give it a try: http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.4-rc4-precise/
PS: Did you check if your BIOS is up to date? As others already mentioned, especially the ACPI stuff tends to be broken.
@Thomas Lenarz: Hmm.. So there seems to be some improvement with the 3.4 kernel, but no final fix. In the meantime, RC4 is out, maybe you want to give it a try: kernel. ubuntu. com/~kernel- ppa/mainline/ v3.4-rc4- precise/
http://
PS: Did you check if your BIOS is up to date? As others already mentioned, especially the ACPI stuff tends to be broken.