Someone brought us her computer for repair because her Windows XP shutdown automatically several times a day. In the beginning the pc experienced this type of spontaneous shutdown only very occasionally, but the situation got worse week after week.
In the end she couldn't work one straight hour on the pc without being interrupted several times by an unexpected, sudden computer shutdown. Without any kind of warning her pc would just instantaneously power-off, no matter whether she was in the middle of editing a document, using her email program or surfing the web.
We're not talking about Windows not responding or blue screens, but total power-down with halted cooling fans like during a power failure.
Needless to say that this is very frustrating, to say the least. Having your pc shutdown randomly throughout the day gets on your nerves.
Take my word for it : a pc with this kind of behavior won't win any popularity contest. No one wants to click the save button every three minutes just because the computer might go down the next second.
We were faced with this stubborn computer with following characteristics :
We started to analyze the pc and checked for the presence of viruses and other malware, but this pc was clean as can be. The sasser worm virus is known to shut down computers, but this behavior was different. Shutdown sequences that are initiated by the sasser worm display a shutdown dialog that allows the user 30 seconds to abort the shutdown, but on this computer no such dialog was even remotely noticeable.
Inspection of the Windows XP event log didn't make us any wiser. Nothing unusual there either.
It took some serious diagnostic testing without any result before someone proposed to open up the computer case. A close look inside the case revealed something interesting :
There were several leaking capacitors on the motherboard. If you don't know what a capacitor is : capacitors are these cylinder-shaped objects on your motherboard that regulate power supply to other components.
We've included some pictures of the leaking capacitors below.
You could say that capacitors sort of play the role of batteries : they accumulate power when there is enough of it and they can release power shortly afterwards when needed.
As you can see on the pictures, a leaking capacitor looks a bit like a leaking battery. You can see a brown substance (electrolyte) coming out of it and the capacitor may look bulged.
Sure enough, when the capacitors in your computer start to look like those in the pictures above, you're computer won't be in good shape. It won't be long before you have Windows XP shutdown automatically on you.
After we had replaced the bad capacitors on the motherboard, the computer worked like a charm again.
Take a look at the replaced, healthy capacitors :
But that's not all ...
... we've had several other computers brought to us for repair with similar symptoms. Yes, that's right, more pc's with auto shutdown symptoms due to leaking capacitors !
In fact, we've had enough cases like this to dedicate this entire page to the problem. If you see your Windows XP shutdown automatically, it might be a good idea to open up your computer case and have a good look inside ...