Re: PC turns itself on while hibernating
Joe wrote:
>
> "VanguardLH" wrote:
>
>>
>> Do you have any scheduled events in Task Manager with the option enabled
>> to power up the computer? I haven't used Nero BackItUp so I don't know
>> what options you can configure for its scheduled backup job, like having
>> it power up the computer.
>>
>> Are you actually powering off the computer or just putting it into
>> standby mode? Power options in Windows might configure the Power button
>> (on the case) to merely put the host in standby mode (and you have to
>> press and hold it in for 4 seconds to actually power off). You would
>> have to shutdown Windows and then during the reboot for the POST but
>> before Windows loaded you would then press and hold for 4 seconds to
>> actually power off. Check your Power Options applet in Control Panel.
>> I've even seen some pre-builts (don't remember if it was Compaq or Dell)
>> where the front Power button would never power down the host but merely
>> put it into low-power mode. You had to reach behind to flip the switch
>> on the backside of the case to actually remove power.
>>
> The only task in the "scheduled tasks" control panel is an HP printer task
> that is not set to wake the pc, but I deleted it just to be safe. The
> software for this HP printer is horrendous so I don't mind getting rid of it.
>
>
> Nero BackItUp doesn't have any wake options that I can find. And I have my
> power management set so that the computer will hibernate when I press the
> power button. It hibernates and then powers off like it's supposed to, it
> just won't stay off. I also don't think it's a flaky power button because it
> never turns itself *off*.
Are you using a wireless keyboard and/or mouse? If so, disconnect the
transceiver from the PS/2 or USB port and test if the host remains in
power saving mode. If that works, select a different channel or code,
or push the reset button on the mouse or keyboard and then the reset
button in the transceiver to do a resync between them. For an optical
mouse, make sure there is no bright light shining at the mouse to cause
an extreme change in ambient light level. Toss a handcloth or unplug it
during a test to see if the host then comes out of hibernate mode.
In your BIOS for the ACPI power option, check if S1 or S3 mode is
selected. S1/Sleep/Power-OnSuspend is where the system appears to be
off, disks are stopped, CPU is stopped but not unpowered so it retains
its context, but RAM gets refreshed to retain its context, and the
system is really running in a low-power mode. S2/Sleep mode is an even
lower power mode than S1 (CPU is unpowered rather than just stopped) but
RAM still gets refreshed. S3/Standby/SuspendToRAM is the typical
Standby mode where the CPU is unpowered so it loses its context, RAM is
in slow refresh mode (to retain its context), and the PSU is in
low-power mode. S4/Hibernate is not completely off but still a
low-power mode where RAM gets copied to a file on the hard disk and the
hardware is completely off. You can still resume from hibernate mode
from events in the BIOS. S5/Off is full power-off mode, nothing is
saved, and requires a cold restart to load the OS.
For your host to be coming back alive, it doesn't look like a device is
awakening the host or it never gets into S4 hibernate mode but instead
just S3 standby mode. It takes time to copy the RAM into a disk file.
When you press the Power button, does the host go immediately into a
low-power mode or is there a flurry of disk activity for awhile (for the
RAM to disk copying)? Going into Standby mode takes a few seconds.
Going into Hibernate mode can take several minutes depending on how much
memory has to be copied (it all gets copied, not just the inuse pages).
4GB would take longer to write the disk file than 0.5GB. If you were to
copy use a batch file to continually write 4K blocks into a disk file,
how long does that take? When I'd take my work laptop to home, it took
a lot longer to go into hibernate mode than standby mode, so much so
that after awhile I decided just to put it into Standby mode to take it
home. If you're only getting into S3 standby mode, maybe Windows Update
is waking your host. Do you have WU set to NOT update unless you start
it manually?
Just because the video goes blank, the hard disks stop spinning, and the
system seems to be off doesn't mean you actually got into hibernate
mode. Something interferes with implementing hibernate mode so all you
really get is standby mode. Sometimes you get a warning that you can't
go into hibernate mode but you might only get one warning. Incompatible
devices (those that won't hibernate) or drivers can prevent getting into
S4/hibernate mode. However, that usually means you can't get INTO
hibernate mode, not that you would randomly come out of it. That's why
I wonder if you really ever do get into hibernate mode and might only be
in standby mode where a bright light flashing on an optical mouse,
someone jarring your mouse or tapping a key, or someone also with a
wireless mouse using the same channel or code as yourself isn't trigging
your system to come out of standby mode.
And now for the truly weird source: the Power button. We had a host
with a broken button. It seemed to pop in/out like normal but actually
it wasn't coming all the way out. A forklift rumbling down the hall,
someone slamming the lab door, or pounding on the desk on which the host
sat could make it power up. The vibration caused a momentary short in
the switch to the 2-pin PwrOn header got shorted to tell the mobo to
tell the PSU to power up. Manager didn't like my hackjob idea of
putting in a new but separate switch so instead we gutted the host to
put its parts into a new case.
By the way, the same instructions in Vista about using powercfg.exe also
applies in Windows XP. Run "powercfg.exe /?" in a DOS shell to see how
to use it. Mentioned this just in case you thought powercfg was just a
Vista thing.