Boot without "quiet" or "splash" on the kernel command-line, but with " --debug" instead
"shutdown -h -H now" from the console note what the last message you see before the hard-disk spins down, up again, and down again -- Hard disk stops and restarts on shut down https://launchpad.net/bugs/61763 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
