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Power supply and motherboard issue

Last response: in Components
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July 22, 2011 6:32:02 PM

Here is a strange behavior by a power supply - could someone knowledgeable about the internal workings of a power supply explain this?

The computer powers on fine one day, but the next it will not POST. No beep, no startup display, but the fans and drives start up. No amount of powering down and up will change the behavior. BUT if I leave the computer unplugged for a week or more, it will then power up fine. This has been consistent over the last 6 months.

Is there some component, like a capacitor that takes a real long time to discharge, that would be at fault here? I am looking for a fairly technical answer.....thanks.

( Gateway SX2802-01 with LiteOn power supply model PS-5221-06)

Saw someone else posted a similar situation with this power supply, but there was no detailed explanation of what likely causes this to happen. I am just naturally curious.

a c 1202 ) Power supply
a c 223 V Motherboard
July 22, 2011 8:38:21 PM

What happens when its been unplugged for a few minutes instead of a week or more?
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a b V Motherboard
July 22, 2011 8:41:46 PM

It's likely your MoBo but i would recommend you buying a cheap $20 450-600 watts PSU...
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July 23, 2011 4:35:09 PM

ko888 said:
What happens when its been unplugged for a few minutes instead of a week or more?


--- A few minutes or even 24 hours is not enough to change any behavior: No normal Beep, even though the drives power up. I did get it to work normally once after 3 days of it sitting unplugged. If I leave it plugged in, I don't think it will ever power up normally - but I haven't tried this for more than a week - I always give up and unplug it after a week to let it "rest".
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a b V Motherboard
July 23, 2011 5:04:09 PM

rwk said:
--- A few minutes or even 24 hours is not enough to change any behavior: No normal Beep, even though the drives power up. I did get it to work normally once after 3 days of it sitting unplugged. If I leave it plugged in, I don't think it will ever power up normally - but I haven't tried this for more than a week - I always give up and unplug it after a week to let it "rest".
-----

The Best way to solve your problem is, Take all your wires and stuff from the back and pull it off and than take the computer and start to take everything apart than put back in to make sure everything is alright, also check if anything got burn because something burning can cause something to fail sometime and it would still work+wont boot sometimes...
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a c 1202 ) Power supply
a c 223 V Motherboard
July 23, 2011 5:49:54 PM

Have you checked the condition of the button cell battery (probably a CR2032)?

Have you tried unplugging the computer clearing the CMOS and plugging it back in and then try booting up?
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a c 144 ) Power supply
a c 156 V Motherboard
July 24, 2011 2:27:31 PM

It is probably the power supply.I suspect that something in the startup circuit is hanging up and it takes a while for some cap to discharge.

Try to borrow a PSU to test your system with.
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a b V Motherboard
July 24, 2011 6:12:28 PM

Buy a cheap $20 400w PSU...
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a b ) Power supply
July 24, 2011 6:50:45 PM

Do NOT ever buy a cheap power supply. That is one critical component that no one should ever cheap out on as it is the only thing that can kill all your computer hardware in one spark.

To the OP.
I encountered a similar problem before in another Gateway model with a FSP power supply where the psu will shut down after 10-20 minutes and won't turn on for a hour or two.

I replaced the psu with an antec ea380d and it was all good afterwards.

So if i were you I'd replace it with a cheap quality psu such as:
Antec EA380D
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Corsair CX 430 V2
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
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