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VOLTAGE DROP OFF FOR PC does not restart

The other day my pc was turned off due to power outage. Since that time the computer would not turn on again, no sign of life, it seems dead.

I did several tests, changed the power outlet and disconnect the wires ... also I have reseated the cards ... but the result is that nothing changes.

What can I do? Could there may be damage to the hardware due to the power outage? Note: the voltage drop is not due to a lightning storm and so is not due to damaged components (burnt card etc ...)

Original Text:

l'altro giorno il pc mi si è spento improvvisamente per calo tensione.... da quel momento non si è piu' riacceso...nessun segnale di vita...sembra proprio morto.

Ho fatto diverse prove, cambio presa di alimentazione, scollegare i fili...insomma ho "mischiato le carte" il risultato è che non cambia nulla.

Cosa posso fare? cosa puo' essere successo? Possono esserci danni hardware per il calo di tensione? NB: il calo di tensione non e' dovuto ad una saetta e quindi escluderei danni causa temporale (bruciature scheda ecc...)

Grazie mille

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Wow thanks for the translation Mukubai! I hope cristian can understand the responses. – James T May 30 '11 at 10:02
Down votes due to translation? Maybe that is the wrong approach. Although the responses will be in English, they should not be too difficult for the questioner to figure out using google translate. Down voting non-English speakers seems kinda lame IMHO. – James T May 30 '11 at 10:51
Does the "Press -key- to enter setup" screen appear and then nothing, or does it not even show that? – Jop V. May 18 '13 at 19:19

I have previously had to completely remove the on-board BIOS battery to get a machine to boot up again. It seemed totally dead ( i.e. nothing happen when I hit the power button) , but removing the BIOS battery for a period brought it back to life.

On another machine I had to close the motherboard jumper that reset the BIOS to defaults in order for the machine to power up.

Both are probably very unlikely, but certainly worth a try before writing off the machine entirely.

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Apperently power surges can happen due to many factors (lightning being least common). I would first try leaving the computer unplugged from power for 10 minutes, then plug it back in again and see if it powers on. If that doesn't work, try it again except also remove the button battery (this will probably reset the BIOS). I'm not sure why this works. Somehow the computer knows that something bad happened and triggered some fail-safe which prevents it from turning on until you drain all power and start over.

Next: Hardware may have been damaged. The first thing I would expect to go bad from a power surge would be the power supply, so that would be the first piece of hardware I would check. You can use some kind of power supply tester. If you are good with electronics, you can try manually testing it as described here.

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I know you've unplugged the power etc so this may not make any difference but unplug the power and hold the power button in for 30 seconds. Then let go, plug everything back in, and try and turn it on. It doesn't always fix it but it's possible.

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What does doing that accomplish? – Simon Sheehan Dec 6 '12 at 21:23
As I understand it, sometimes there's power that's stored in certain places that hasn't properly been cleared out. I don't understand it but I've had it fix various devices before including pc's/laptops. – Codezilla Dec 7 '12 at 0:01

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