Tom mentioned heat as a possible problem, and I would like to add a bit to 
that.  With heat, the temperature builds to a critical level, and then, 
hopefully, the computer shuts down.  This would indicate that the computer 
is shutting down at about the same time, no matter what program you are 
using at the time.  A good way to clean out your computer relatively safely 
is with compressed air.  You can buy a can of compressed air at a hardware 
store (about $5?) or a six-pack at someplace like Lowe's for much cheaper 
per can.  (You can always use it for cleaning behind the refrigerator, etc.) 
You can then "dust" the insides of your computer without touching anything 
except the side of the case, which you have to remove.  Another thing that 
you can try is to open the side of the case and run a floor fan on it, 
seeing if the computer still crashes, or still crashes at the same time.

If the computer crashes immediately upon startup (at possibly random times), 
it might not be overheating unless for some reason the contact between the 
cpu and its fan has become bad.  (Not a good thing to happen, as a cpu will 
burn out pretty fast.  Been there.  Done that.)  If you are inclined to mess 
with the cpu, you can (after doing the stuff in the first paragraph with no 
luck) try removing the cpu fan, cleaning joining surfaces with a Q-tip, and 
replacing the thermal grease.  Make sure that you ground yourself to the 
case frequently by touching it, work on a static-free surface, and unplug 
your computer!!

If neither of these work, then it is likely not heat.

If you can get to the point where you can do something in Windows, it is 
**probably** not the power supply.  Diagnosing the power supply is another 
whole topic that we might look at if the above suggestions do not work.

HTH

Dean Kukral

----- Original Message ----- 
From: "Sybilgal" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, March 29, 2008 12:36 AM
Subject: [PCBUILD] Diagnosis question


Hello all,

My computer recently started shutting down on its own.  Nothing else has
changed, nothing else going on.   The first time it happened, I assumed I
did something with the keyboard causing this to happen, but that wasn't it.
Now, though it will begin to start up, it turns itself off again, even
sooner.


Can anyone advise me as to a method to diagnose this problem?  I assumed it
was the power supply, but others have told me that were that the case it
would not start at all.

I really don't want to fork out $200.00 to diagnose and then after that, end
up by buying a new MB, power supply and memory...UNLESS of course, I have
too!

Any suggestions to assist in this discovery would be highly appreciated!

Thank you all, in advance...

Kathleen LaValley

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