Comment 17 for bug 36158

There is a lot of bugs related to "system not powering off on shutdown". I think there are two types of problems. One type is people that have apm enabled by default and the other type is people that have acpi enabled by default. Those with apm can solve the problem booting with the acpi=force argument, but the other type has no solution till now.

I think i found a workaround for those with acpi enabled. When i shutdown my system, everything is ok, but when the machine is supposed to power off the console says "acpi_power_off called" and nothing happens. I discover that when i hibernate the machine (hibernate works out of the box in this machine, thanks ubuntu devs!) there is a power off.

The workaround i propose consists of using S5 acpi state to power off the machine. In /etc/init.d/halt replace the line that says "halt -d -f -i $poweroff $hddown" with "echo 5 > /proc/acpi/sleep".
I don't know if is a good or a bad solution, but it works for me and i haven't found any problem using it.

Sorry for my poor english. It isn't my native language.