I've been searching for a while on this problem and haven't found much. Whenever I try to shutdown my pc, it reboots. It doesn't matter if it using the Gnome shutdown button or 'shutdown -h now'. During shutdown, the screen will display "Shutting down..." then "Shutting down...re-executing /sbin/init" The status messages will even display "Halting system", then poof, it fires right back up. I've tried editing the BIOS to turn off/on PM, no luck. Adding acpi=off to grub.conf doesn't help either.
Any ideas would be greatly appreciated. There is also a problem with it not resuming from suspend or hibernate, but one issue at a time.