PC keeps shutting off randomly

[terry5880]

Hi all I got custom built pc I built maybe 5 yrs ago or more had no problems till now.. yesterday it decided to just turn off and would not turn on so I opened up side casing after unplugging it then plugged back in and it came back on was on for few hours I then shut down and went to bed ..woke up this morning and it wouldnt turn on again so I unplugged and plugged back in and it worked again ..could it be psu is failing..any info please ask

 

[terry5880]

UPDATE pc turned on fine this morning and has been on good few hours so really puzzled

im running asus motherboard 2gb corsair ram core 2 duo cpu with nvidia 8800gt graphics card windows 7 and a 750watt psu...some one please help

 

[Tmagic650]

My wife's PC is doing this too. It is a MicroATX model with a 275 watt TFX power supply. I have seen this in a few more PC's over the years. It seems like a power supply issue, but it can also be the motherboard

 

[terry5880]

Thanks tmagic always count on you to give input bud.. I think its psu too gonna format it and sell to a shop

 

[Tmagic650]

Okay terry5880, no problem... Good luck!

 

[terry5880]

So far since last message been turning on and off fine so deffo got to be psu ..thanks again

 

[Tmagic650]

No problem, glad to help

 

[BosPatrollie]

I have recently worked on 3 machines displaying similar symptoms ... turned out to be dust on 2 of them and a faulty capacitor on the other's motherboard. Another common issue, like mentioned already ... is the PSU. On one of the 2 dust affected machines, it was dust inside the PSU causing intermittent shorts and spikes. I advised the user to look at replacing it as chances are the short caused by the dust could very well have done some lingering damage.

 

[Tmagic650]

BosPatrollie,
Dust is not an issue here. Both Terry5880 and I are smart enough to have ruled that out before changing the power supplies...

 

[BosPatrollie]

Tmagic650,
My post was not intended to offend you or Terry or question your intelligence. I merely stated what I found to be the cause there and what I advised that user to do. Someday somebody might read this thread when they browse for answers and that could very well end up being their issue.

 

[Tmagic650]

I can imagine that you live in an area where the prevailing dust is conductive like parts of Colorado or Pennsylvania or even Kentucky. I have seen the inside of a computer so full of dust that it was like a blanket covering the entire motherboard a half inch thick. This was causing overheating

 

[BosPatrollie]

Yeah ... overheating happens quite often is such scenarios due to the fans either not spinning properly (or at all) and the heat sinks being clogged up. Holy COW ... 1/2 inch ... that's enough dust to start a mini-green house inside the tower case!

 

[Tmagic650]

I changed the power supply in my wife's computer and it is shutting off and turning on normally now