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The strange nature of this problem is what is stumping me. I built my computer about 7 months ago using all new parts off of Newegg (not a kit or anything).

One day, I wake up and turn on my computer. I press the power button and it turns on, but then back off after half a second.

I press the power button again, this time nothing. I continue pressing the power button while at the same time turning the power supply on and off (to try and reset things). The power button still does nothing.

But then, after about 5 minutes - voilà! It works just fine like nothing was ever wrong.

It goes for an entire week working just fine. Then, one morning, the entire process starts again. I press the power button and it comes on and then right back off. I press the power button several times and nothing happens, and then it works again after a couple minutes of trying.

What is going on with my computer?

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I regret I had very similar symptoms with an HP G61. A repair shop reported they had a warehouse full of that model with the same problem and did not know how to fix it. Turned out to be on board voltage regulation failure - and terminal, though my PC was barely 18 months old. – pnuts Dec 12 '12 at 22:06
So it was a faulty motherboard? Did they ever find a solution? – hellohellosharp Dec 12 '12 at 22:08
Yes. No. My solution was to buy an Acer (my repair man said he never got to see many of those!) - and never any HP product ever again (since I had a Pavilion before (cost ~£5k) that had an acknowledged manufacturing defect (graphics card overheated)). – pnuts Dec 12 '12 at 22:15
Did your problem happen all at once or just once a week-ish like mine? – hellohellosharp Dec 12 '12 at 22:22
hahahaha i like your spelling of Voila better hahaha – im so confused Dec 12 '12 at 22:27
up vote 2 down vote accepted

You also didn't say whether or not the computer was custom built with all new parts or, perhaps, some were scavenged from other computers.

Try the following -

  • double-check that all of your wires are connected properly (including the wires leading to the switch)
  • check to make sure that you don't have an accumulation of dust or other debris (carefully blow it out with a can of compressed air if you)
  • check the power supply by transferring it to another computer that is known to be working
  • install a new power supply appropriate for the other components

This isn't an exhaustive list; just things I've encountered over the years building my own systems.

If nothing suggested here works, take it to a local computer repair shop.

(Edited to reflect updates to the question.)

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read the question again... It was clearly edited to say he built it himself – MalwareManiac Dec 12 '12 at 22:00
When I started typing, it didn't. – Mike Chess Dec 12 '12 at 22:03
I know Im letting you know that he edited it – MalwareManiac Dec 12 '12 at 22:04
Thanks for giving me a simple checklist of things to try. The next time it happens (and it will), I will try some of these things. The rarity of the issue makes it difficult to troubleshoot though.... – hellohellosharp Dec 12 '12 at 22:06
@hellohellosharp The term is "intermittent" – barlop Dec 29 '12 at 1:19

Try changing the power supply.

Try changing components. Power supply. That power supply in another machine. Another power supply in your machine.

It's going to be either your power supply is bad or not plugged in right, or your motherboard is bad. So if you prove it's not the power supply, then process of elimination, it's the motherboard. But i'd think it's the power supply if anything. I am not sure how a bad motherboard could behave like that though maybe it could. You'd see if you bothered to do some troubleshooting.

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I DID build the computer actually, sorry I guess the term "Custom-built" is slightly misleading. I have access to the interior. I tried switching some things around but nothing seemed to show the problem. I wasn't sure if my power supply was stable so I did not want to touch the wrong thing. – hellohellosharp Dec 12 '12 at 21:51
@hellohellosharp it's safe to remove a power supply unit(PSU). A PSU is (also?), an ACDC adaptor.All the low voltage/current DC on the outside is fine+covered.The danger is opening up the PSU itself and touching it while it is on.There might(i'm not sure) be a danger in opening a power supply with no power on but getting zapped by charge in a capacitor.But i'm just talking about removing the power supply, not taking the power supply itself apart.You won't harm anything by removing the PSU.There's no danger.This stable/unstable thing in your mind is nonsense you might've thought of in a dream. – barlop Dec 12 '12 at 21:54
Okay, next time it happens I will try removing the power supply. What about the Front Panel Connections? Is it possible that my case has a loose connection with the mobo? – hellohellosharp Dec 12 '12 at 21:57
@hellohellosharp front panel connections wouldn't be my first suspicion, but it is very mysterious. If you swap the PSU and find it doesn't help, then look at the front panel connections. – barlop Dec 12 '12 at 22:02
let us continue this discussion in chat – barlop Dec 12 '12 at 22:17

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