Holy cow, I wrote a book!
Sometime last year
wanted to know why the screen goes black when the system automatically
hibernates due to critically low battery power.
Shouldn't there be some sort of feedback to tell the user,
"Hey, like, I'm hibernating, don't worry"?
The power management folks explained
that they turn off the screen
for a reason:
They're trying to save your data while they still can.
When the system gets the "Oh no, the battery is about to die!" notification
from the hardware,
there's no time to lose,
and even less power to waste.
Keeping the screen lit takes a lot of power,
so turning it off might make the difference
between a successful hibernation
and loss of data.
Mind you, this doesn't all happen without fair warning.
Before the battery goes critical,
you will get a low battery warning balloon saying
"Oh dear, things are getting pretty bad,
you really should wrap things up
before I'm forced to stop the car!"
It so happens that this particular customer had a system
with a buggy BIOS that fails to notify the operating system
of changes in power level with sufficient granularity.
The power level went from "okay" straight to "critical"
with no steps in between.
As a result, Windows doesn't find out about the low
battery level until it's already at critically low levels.
Observe that I wrote "The power management folks explained".
I am not the expert here; I'm repeating what I've heard
in the interest of getting information out.
it looks like
the Windows Mobile PC Team Blog has gone dark,
so it's not clear to me where you can ask your questions.
(There is a more general site on
Microsoft and the Environment, however.)