Re: APM doesn't really work

[Craig B <craig@spam.not>]

David Kanter wrote:
> 
> I compiled a new kernel last night with APM support. When I boot up, I get the message about APM BIOS. However, it doesn't work all that well.
> 
<snip>

On my Hamm system, I had a hell of a time just getting my monitor to
shut down let alone suspend the system or put it on standby.  Basically
what I discovered, in my case, is that using the BIOS timers is
ineffective for everything but the drive spin down.  For some reason the
system overides them.  I did find that if I set BIOS timers to a really
low value, then they would work but having the system suspend after one
or two minutes of idle time is not very practical.  My primary goal was
to spin down the drives and shutdown the video and I was able to
accomplish that.  I set the drive spin down timer in the BIOS and that
seems to work OK.  For the video power down at the console, I added a
couple lines to my /etc/init.d/rcS file as follows:

setterm -powersave on
setterm -blank 15

For the video power down in X, I added a line to my ~/.xinitrc (for
startx) and /usr/X11R6/lib/X11/xdm/Xsetup (for xdm) as follows:

xset dpms 900

If you have a DPMS compliant video card and monitor, the screensaver is
somewhat reduntant since it is much better to power down the video in
lieu of activating a screen saver. In that case, disable the screensaver
using xset and/or setterm.  There are some differences in the way Slink
handles this stuff so take this with a grain of salt.

My understanding of APM is that it is only beneficial for laptop
applications.  I can't say for sure, but I don't think it does much more
than add battery support.

Hope this helps.