how to enable auto power off

[Charles Howse]

> > I read man 4 apm and man apm and they both refer to laptops.
> > I also would like to get auto power-off working on my 
> desktop system.
> > Will the instructions you gave work for my system?
> 
> Assuming it supports APM, sure.

OK, I just checked the BIOS, and it does have Power Management support,
and when I boot, I also see 'ACPI function enable' in the post msgs.  I
realize that ACPI is not supported in FBSD < 5.x.  I'm running 4.8-p4.

I've never used Power Management on any of my computers, so this is new
territory for me.
I would assume that I need to set Power Management to 'enabled' in BIOS,
or no?

If yes, (and I realize you can't know my other PM options) should the
defaults be OK?
Any particular option that you know of that I should pay special
attention to?  I don't have the MB manual for this box.