Blown Power Supply?

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Had a storm the other night and the power loop was pulled away from
the house
causing 220V to surge through one leg.  My computer was
still on when it
happened and it screwed the surge protector, now the
computer will not do
anything.  It shows the on light for a second
when I turn it on, then it goes noise, nothing.  Is it the
power sully?  Could I just replace it?

Re: Blown Power Supply?

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If you are lucky. it was just your powersupply
might as well try another one

Re: Blown Power Supply?

Surges can do any amount of damage, power supplies are easy to get and
cheap enough... but is this the only problem, sure is a good place to

If you look around it there should be a label on with the Wattage,
you'll need one with the same wattage or greater, for example a 300W
PSU can be replaced by a 400W but risky replacing it with a 200W.

Pentium CPUs they need an extra 12V connector for the mobo where as
AMD's don't, so take note how many leads from the PSU go to the

Just a matter of unplugging, keep notes if you are not sure, one or
two plugs will go to the mobo depending on CPU as mentioned,  the
rest are the 12V & 5V supplies for the HDD, CD rom, floppy or
whatever, here you will find loads of plugs they are all the same.

Some PSU's will have an extra socket on the back, this is to power the
monitor, some may have a power switch on these are for user
convenience otherwise they are the same. The only thing to watch for
is some may have a voltage selector switch which must be set for your

The connectors in all cases are non-reversable, if you had a spare
computer with an identical PSU (Power Supply Unit) a swap over would
prove one point or the other.

If you have a dial-up modem I've seen this to be damaged and nothing
else funny enough after a lightning hit...  so if you do have dial-up
modem try pulling the modem out and booting up.


Re: Blown Power Supply?

On Fri, 19 May 2006 19:30:06 GMT, no@spam.invalid (wright45)

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Unplug the power supply from AC for 10 minutes.  Plug it
back in and try it.

Unplug the power supply from AC again.  Open system and use
the clear cmos jumper or remove the motherboard battery for
10 minutes.  Reassemble and retry it.

You might take voltage readings of the power supply if you
have a multimeter.  Disconnect the  PSU from everything and
short the PS_On pin (usually pin 14, a green wire) to ground
to turn it on (presuming it is an ATX, you haven't provided
any specific system info).  If it is a less common or
proprietary system or power then Google for the specs on it,
whether anything else or different is needed.

It could be the power supply, or possibly it is fine but
something else like the motherboard is damaged.  Having
another power supply to try could be  helpful, as could
(unplugging AC power first then) removing all the extra
cards and devices from power and data cables, leaving only
the video, 1 memory module, CPU and heatsink/fan.  Then
reconnect AC again and try it.

I assume you are not trying to use it plugged into any surge
protector that was plugged into an outlet during that event.

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