UPDATE Swapped from the 2.6.15-26-386 version of the kernel to 2.6.15-26-k7 (to match my Athlon processor) and my PC now shuts down as expected with no change to the kernel boot options.
-- Power down after shutdown does not work... https://launchpad.net/bugs/43961 -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
