PC Fault diagnosis

[MontyVeda]

my pc keeps randomly powering down... is the PSU the most likely culprit? Or possibly the power switch on the box seeing as it gets pressed daily (ish)?

I'll try to keep this breif because my last attempt at explaining the prob was lost when the pc powered down.

could a fault on the dvd drive, hard drive or motherboard/cpu cause it to just power down (as if the plug has been removed)?

Vague I know but any help/advice would be appreciated.

sometimes the power just goes and i have to flick the on/off switch on the PSU itself before trying the button on the case, sometimes it comes straight back (lights on the case) but doesn't boot up the PC until I press the restart button on the case.

it's quite a cheap case so maybe the on/off/restart buttons are on the way out. Can these be bypassed permanently?

 

[Dragonwight]

My first stop would be the BIOS to see if the thermal warning is switched on and what temp it is set too. If its turned off your get no warning and your PC will just switch off as you describe if its overheating.

 

[MontyVeda]

My first stop would be the BIOS to see if the thermal warning is switched on and what temp it is set too. If its turned off your get no warning and your PC will just switch off as you describe if its overheating.

I've had the PC for a couple of years so i guess bios settings are OK as I daren't fiddle with them. However I was suspecting the unusual heat may have been the problem. Will have a look. cheers

 

[henshaw11]

Might be as simple as the fan in the PSU, I've had that on my work desktop in the past. Probably worth checking the other (cpu, motherboard chipset) fans whilst you're at it, and that they're not clogged up with dust..

 

[MontyVeda]

they had sh!t loads of dust in 'em and after it worked once that had been sucked out, I figured I'd fixed it. But it's still going down as and when it wants. Will be vacuuming it monthly from now on though.

edit... the PSU is quite hot to touch after being on for around 45 mins... is that normal?

 

[Dragonwight]

PSU does get hot after a bit especially if made in gung ho china. Your best bet is to check the temperature in the BIOS you dont need to change anything. Just go into the BIOS in the menu there will be something like PC health listed go into that and leave the machine running for an hour on that screen and see if the temperature rockets, it should also tell you if all the fans are running.

 

[MontyVeda]

cool thanks for that dragonwight

 

[ian turner]

install speedfand keep an eye on the temperatures and voltages (ignore temps that have flames next to them on boot as
those are non existant probes,likewise for voltages just check the 3.3,5v and 12v readings)

 

[MontyVeda]

well after removing even more dust from in and around the PSU, and almost blowing my face off* ...it seems to be back to normal again. I think 18 months of dust being sucked in combined with last weeks heatwave was too much for it.


*tried to dislodge dust with an air duster... upside down so loads of liquid came out into the PSU, turned it right way up and tried again... no liquid this time, just air... hit the power switch and WHUMPH! a big ignitey fire ball the size of a beach ball instantly emerged to around the PSU and disappeared as quick as it appeared. Singed all the hairs on one arm and probably burnt the remaining dust in the PSU... PC still booted up tho

 

[srw]

Have you tried turning it off and .... oh.

 

[the_mikey]

Had that problem with a laptop, used an airduster to blow all of the dust out of the cooling system and it was fine after that.

 

[GTTTM]

I had this with a PC a few years back, it eventually powered down and refused to switch back on and it was then we discovered that it had burned out.............too much hardware for the motor and fan to cope with and "poof" (well not quite pooof - but it was fried) -