The Inspiron 1100, 1150, 5100, 5150, and 5160 all have thermal issues best
managed by keeping fans and ventilation areas clear of all dust and dirt and by
using i8kfangui to force the fan to cut in at high speed at a pretty low
temperature, say somewhere in the 120's Fahrenheit.

Dell settled a class action lawsuit on 5150 thermal issues by extending system
warranties and replacing system boards.

Despite the fact that these computers used mostly desktop P4s and some desktop
Celeries, they are pretty decent when allowed to run cool. Toshibas and other
laptops of the era all often used desktop P4s... Ben Myers

On Sun, 11 May 2008 22:47:58 GMT, "William R. Walsh"
m wrote:

Hi!

Now my laptop sometimes suddenly shuts down with absolutely
no message.

This is a thermal shutdown. In fact, if I'm not mistaken, the Inspiron 1100
line is famous for this very problem.

However, it's not that straightforward. I've seen evidence that these
systems can shut down because of a defective sensor. So even when the system
is working fine, it might just *poof* and power off. If yours has this
problem the only cure I know of is a new motherboard. Which may have the
same problem down the road.

You might get lucky if the system is really overheating. This can be proved
by running the CPU up to 100% utilization and watching for a failure to take
place. By doing this a few times you can establish a pattern. From there you
can look at what happened and see if the shutdown is really due to thermal
reasons. Use a program like Prime95 (which has a testing mode that works
really well for this purpose) and get the system good and hot. See if it
shuts down.

Should you find that the system is really overheating, you can do something
about it. On many laptops, the fans inside blow through a radiator-like
structure instead of an actual heatsink. Heat pipes are used to connect the
hot running parts to these radiators. Over time, these radiators plug up and
lose a lot of efficiency (and effectiveness). If you can find the ones on
your computer, use a fairly high pressure, clean air source to blow
backwards through them. Chances are you will see a LOT of lint come out.
Keep doing it until no more comes out.

If you can figure out how to safely remove the fan from the computer, you
might clean it as well. (That's not for the faint of heart, although Dell
does provide service manuals that are pretty well written.)

To give you an idea, you might find the following page useful:

http://12.206.251.215/d800fanrepair/ (broadband connection suggested)

It's about my Latitude D800 and the noisy but seemingly undocumented
secondary fan inside it. You can see the radiator like structure that the
fan blows through, and how it can get plugged up.

Power supply problems can cause abrupt shutdowns, but you're more likely to
notice the supply itself malfunctioning (the little light on it goes out
unexpectedly, or you hear bad sounds like sizzling), or failing to charge
the battery. In really bad cases, the system won't power up at all, or
claims that you aren't using a genuine Dell power supply.

Good luck!

William