Computer turning itself off on boot-up

Hatake · 2 Sep 2006 at 09:11

My computer has recently started turning itself off during boot-up and I'm unsure of why its doing this.

I've not installed any new components or anything although I have moved it into a new room a little while ago but I doubt that would have anything to do with it as it was not dropped or anything.

I got a virus a while ago but got some anti-virus and anti-spyware programs installed to clean my windows but I think it's more likely to be a hardware problem.

When I press the power button on my computer, everything is starts normal, no beeps or anything, although nothing comes up on the screen but I don't know is it on long enough to actually display anything.

In about 5 to 10 seconds, the computer turns off and when I press the power button again, nothing happens. If I wait a few minutes or turn it off at the plug and then back on and push the power button, the computer powers up again but turns itself off after 5 to 10 seconds.

It does this for a while but sometimes it starts up fine and the computer stays on until I turn it off, so I am totally stumped.

My mate said I might have blown the processor but I haven't done anything that would be likely to fry the thing and it doesn't explain why it sometimes boots up fine and works fine.

I'm thinking it might be a dodgy power unit but I was wanting a more experienced opinion before I go out and buy a new one. Anyone got any ideas on what it might be?

Hatake · 2 Sep 2006 at 09:59

It could be a software problem?

I used McAfee virus scanner to remove the virus and its not detected anything since when the computer decides to boot up.

How would I get readings from my power unit?

When the problem happens, I can't get the computer to stay on for more than 10 seconds at a time so taking any readings when the problem is present will be hard.

I plan to open up my computer later when I get home from work to see if any components or wires have become loose but I don't see how that would be possible.

Seeing as the computer doesn't actually boot-up windows before it turns itself off, I think the problem is mainly hardware.

Hatake · 2 Sep 2006 at 10:30

Thats a good point, I never thought about listening to see if the HDD is accessed or not.

IIRC, I think I heard the DVD drive spinning up just before it turns off. I might try disconnecting the optical drive and then see what happens.

On a side note though, what would be the symptoms of a broken processor?

Hatake · 2 Sep 2006 at 10:48

thanks for the quick reply but when you say wouldn't work at all do you mean the computer wouldn't even power up when the button is pressed or do you mean it would hang on start-up with the BIOS beep?

Hatake · 2 Sep 2006 at 10:58

No worries. Thanks for your help, it's a relief to hear it's unlikely that the processor is broken from the problems I've described.

But then again, if it's the power unit, when my computer does decide to boot up fully, why doesn't it turn itself off when I'm using it?

Is it because the PSU is possibly faulty and not just underpowered or just the first few minutes of boot-up require more wattage?

Hatake · 2 Sep 2006 at 11:16

yeah, I'm thinking a faulty PSU too.

I think the lack of wattage thing is just hopeful thinking lol. Thanks again.

Hatake · 6 Sep 2006 at 03:38

Well I'm pretty sure I've narrowed it down to the PSU. I took the computer apart and cleaned everything, made sure everything was properly seated, all the fans were running, and unplugged everything to clean the connectors before reconnecting. No problems there apart from the usual gathering of dust on stuff.

My computer starts up fine now but the PSU makes a horrible buzzing sound until a few minutes after windows has completely started up. The PSU fan was clear of foreign objects as well.

Either way, it doesn't sound particularly good or healthy. Even though my computer boots up now, with previous behaviour and now this loud buzzing noise, albiet for a few minutes, I think its probably best to change the PSU.

Hatake · 6 Sep 2006 at 16:44

Well if I take it to a repair place, I have no guarantee that the person taking my computer is going to be able to identify the exact problem or are they just gonna tell me I need to replace X amount of parts for an overpriced amount +labour.

It's the PSU that makes the horrible noise on initial startup and is the only plausabe reason I can see for my computer to turn off on startup. Everything else sounds healthy and when my computer does boot-up, nothing stops working. I'm almost positive it's a faulty PSU thats causing the erratic startup.

Plus, either way I'll be changing the PSU due to the noise its recently started making anyway. That noise can't be healthy so if my computer is still erratic after the swap, I won't have really wasted any money and I can start looking for the problem again.

Thanks for the concern though