laptop powerup a fire hazard?

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A question for the collected wisdom:

Modern laptops have ability to schedule a boot from power off when some
time is reached on the internal clock chip.  This has obvious uses, but
in a laptop it has hazards that are almost as obvious.

When a laptop is on AC power, there is probably little harm if it boots
while unattended.  But a laptop in a backpack sleeve, or stored away in
an unventilated drawer, may have its ventilation powers entirely
blocked.  For a machine to boot and run under such circumstances is
clearly hazardous to the machine, and under some circumstances may
constitute a physical fire hazard.

I have experimentally verified that Windows Media Center (for example)
will boot a machine if it has a recording scheduled.  This application
might be particularly dangerous, since it runs a machine fairly hot with
disk and processor activity.  Windows Update has also been implicated as
starting an unpowered machine to check for updates, even if it is not
permitted to install automatically.

I generally leave my machine in hibernate, and twice in the past six
months I have discovered it repowered.  Once it was in a backpack, and
once when stored away in a drawer.  Now, I have the on-battery power
settings to place the machine in standby fairly soon, so the machine was
in standby and after entering standby was not generating large amounts
of heat.  But a colleage similarly had his machine turn on in a
backpack, and he apparently did not have the machine configured to
standby.  He claimed it was almost too hot to touch.

These machines are of different manufacture, and one was XP and the
other Vista.  So the problem is generic, and not necessarily even
specific to Microsoft.  The problem is that a boot might be scheduled
with the OS by a large number of applications.  It is hard to be sure
one has discovered and controlled them all.  Trashing a machine, burning
down a house, or firing airplane seems a serious price to pay for
missing a setting.  I now remove the battery when storing the machine.

In my opinion, the motherboard should never boot a machine when on
battery powered without some definite confirmation in advance (at power
down?) that this is desired.  I've reported the hazard issue to the
laptop manufacturer and am waiting for definitive response.  meanwhile,
does anyone have any thoughts or anecdotes to share?

Re: laptop powerup a fire hazard?

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Normal use 20 Watt.

Normal surface complete about 0,2 m²

With a themal insulation of u=2, theoreticall 50 degree Celsisus
difference possible.

Roland Mösl cars and traffic building and live

Re: laptop powerup a fire hazard?

Steven M. Haflich typed on Sun, 16 Mar 2008 16:20:01 -0700:
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Yes I have seen both desktops and laptops suddenly power up out of the
blue. The PIA fix of course, is figuring out what woke it up in the
first place and then disabling it. Once this is done, I have never had
any more problems at all.

And a fail safe method is a very simple method and it works perfectly
every time. Just remove the battery if you are not using it on battery


Re: laptop powerup a fire hazard?

Not an issue; the laptop will shut down if it over heats.  In fact, the
heat sinks and fans often become clogged with dust and overheating and
spontaneous shut downs is one of the most common problems that laptop
service technicians see.

Steven M. Haflich wrote:
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