Since my AAO was resurected from the black screen of death, thanks to macles bios overhaul tips, I have to press the on/off button to shut it down. On restarting it needs to FSCHK because / wasn't cleanly unmouted. I also run Mint Linux 4 from a USB 8 GB stick, and it shuts off nicely, so I do not think the Linpus problem is bios related.