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recently my computer started to behave like an old car and won't start up anymore unless I flip the power switch repeatedly. What happens when I power it on:

  • CPU fans spins briefly and very slowly, then it stops
  • Same with GPU fan
  • No BIOS beeps or HDD activity
  • Screen stays black

After turning it on and off for like 10 times, it'll eventually boot like normal and run smooth without any problems what-so-ever. But I'm worried it might eventually die completely.

Anyone know the most common cause of this? Maybe I should just leave the computer powered on? :)

Okay just a little follow-up: Just one day after posting this my computer now refused to turn on at all, it seems my old mainboard just died (Gigabyte P35 DS3R for reference). I replaced the mainboard earlier today and everything is working fine again.

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up vote 5 down vote accepted

If I were you I would unplug useless stuff like Hard drive, CD drives and try another power supply.

If nothing else work, seems like your motherboard is having problem.

Check for bulging capacitor on your motherboard, it's a common behavior when this happen.

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ok thanks, definitely gonna check for bulging capacitors later today – Jan Gressmann May 9 '10 at 19:16

Sounds like a faulty power supply (inside the computer), or maybe the switch is broken.

Can you open the front of the computer (UNPLUG IT BEFORE DOING THIS) and examine the switch, check if there spring mechanism is functioning correctly.

But I would start with the plug, switch to a different power cable if you have one.

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thanks, though I'm pretty sure the switch itself is fine. As I said it turns on (LEDs are on, fans start to spin) but it just doesn't start to boot like it should. – Jan Gressmann May 9 '10 at 19:18
I had a problem with a gateway desktop where the power button was sticking, so it would start run for about 10 seconds, then shutdown. What was happening was the computer was interpreting that the button was being held, just as you would do when you want to force a computer to turn off. If you're happy that that is not the problem, swap the power supply out. – bryan May 9 '10 at 19:28
I know of a vacuum that requires the repeated flicking of the power switch to start... but that's a different story. – Nathan Osman May 9 '10 at 22:45
Unplug before opening the front. HA wimps :D – Wuffers May 10 '10 at 22:11

I am having the same thing happening with my powersupply as well.

I am using a Stealth X Stream OCZ series PSU. i don't recommand that series to nobody. YES they are affordable... but the caps inside the psu are cheap OST caps.

my psu just started doing this, had it for a little more then 3 years! oh and did i mension it was a 3 year warrenty? well i guess you get the point.

Anyway, what i think is the most important. Is to check the 12V and 5.5V sensor on the bios. if the computer ever start!

If you're 12V is lower then 11.88V then don't let that power supply on your computer.

same goes for 5.5V of 5.12V or lower.

Running your psu with low voltage sensors is comparable of riding at 120 mph at night with a toyota corolla during winter. (it dosn't matter how lucky you are, when it goes off it might as well bring your hole computer with it.)

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I experienced a similar issue two weeks later: it was the power supply...melted.

The first time it happened, I managed to use again my machine rebooting several times and for a dozen of days it worked just fine. Then it happened again, and I couldn't (yet) power it on, but I noticed an overheating in the upper/rear section of the case (where the PSU was).

I asked my usual computer store to let me give a try with one of their PSU and the pc worked again: if you haven't found yet what it was about, you could try another power supply. It could do the trick.

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