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Resolved Question

computer turns on for split second, then back off. help

Jan 22, 2014 5:09AM PST

so the other day i was surfing through the internet. out of nowhere i here a popped it turned out to be my cooling fan (PSU). so i switched it with an old one that works tested it. either way the computer turns on for a split second then back off and leaves a blinking red light which wont turn off unless i cut the power. the only fans that spin are the graphic card and the PSU one's. other than that the heatsink fan nor the one that is facing out pulling air in turn on. i tried removing each component one by one but nothing works. don't know what to do.
computer model is : DX 5150 mt tower model
running : windows 8 64 bit
ram : i believe 3.50 GB of ddr1 ram
graphic card : galaxy nvidia geforce 210 1gb ddr2
heatsink fan is : freezer 7 pro rev.2
CPU : athlon 64 x2 4200+

Discussion is locked

killmehere has chosen the best answer to their question. View answer

Best Answer

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computer turns on for split second, then back off. help
Feb 4, 2014 7:15AM PST

Hi,
I suggest you if your are used computer then all connected cable disconnect some time, and also SMPS power cable disconnect in mother board. and some time wait and again reconnect all cable step by step be carefully. Connect before you check SMPS proper work or not. If SMPS ok conduction then may be you any device loose so proper connected.

Thanks..

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hi..
Feb 4, 2014 11:02AM PST

What is SMPS
Thank you..

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Answer
Did you inspect for BAD CAPS?
Jan 22, 2014 5:14AM PST
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thanks for the quick reply but still nothing.
Jan 22, 2014 5:29AM PST

all caps seen to be looking fine none are burned. Sad

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I rarely see burned.
Jan 22, 2014 5:51AM PST

I see dome tops, leakers, tilters, blown bottoms and we always check all boards and the PSU board.

The criteria is perfection. If that passes then we unplug parts till it powers up.
Bob

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thanks
Jan 26, 2014 11:38AM PST

still nothing i don't know what happened to it.

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So you got down to 2 parts?
Jan 27, 2014 1:00AM PST

On cardboard I can reduce a desktop to 2 parts. Power supply and motherboard. NO OTHER PARTS are needed to execute a power up. If that fails I'm looking at the possible bad parts.

If I was so inclined I can test the PSU power up with (google this) "PSU GREEN WIRE TEST" and a Volt meter.
Bob

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hey.
Feb 4, 2014 10:53AM PST

The fan turns on when I touch the paper clip to the two wires ( black, and green) so problem is the motherboard?

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(NT) Did you use your Volt Meter for the rest of the Green test?
Feb 4, 2014 2:13PM PST
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..
Feb 5, 2014 4:12AM PST

yes but still not turning on after test. power supply works fine.

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So let's give the PSU a pass.
Feb 5, 2014 4:14AM PST

Change the other part. Remember that we can drag this down to just 2 parts. So let's change the other part now. What happens?

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...
Feb 5, 2014 4:14AM PST

also. does a psu blowing up inside cause the motherboard to fried as well. cause thats what started the problem the fan blew up. i mean not like explosion just inside the fan.

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Could.
Feb 5, 2014 4:27AM PST

That's why we have ways to narrow it down. I rarely have to take it down to just 2 parts but once in a while have to do that. The GREEN WIRE PSU test is not all we can do but is a quick test to see if the basics are OK. To really test a PSU we need to put a load on it. At the shop we have dead HDDs and braindead motherboards that won't fry PSUs but supply a light load to give us a good idea if the PSU is good enough to keep around.

Full load testers are best but rare today.
Bob

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:)
Mar 2, 2014 8:12AM PST

sorry i took for ever to answer but it work now it turns on it was the motherboard that fried. thanks for the help and wasting your time on me. where do i click to put as solved?

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(NT) Thanks for posting back...always helps to know the outcome.
Mar 2, 2014 9:46AM PST
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check the caps in the PSU too
Jan 22, 2014 11:43PM PST

They were part of the bad caps era too.