PSU keeps blowing

  SimianBenzoate 18:35 11 Jul 2004

i have just moved house and now my pc refuses to turn on. it used to do this before but if u kept pressing the on button it would power up...not anymore tho.

so i bought a new psu, fitted it no probs and it powered up fine. when i came back a bit later, it had turned off and when i turneds it on again, the psu popped and some sparks flew out the back...which is, i assume, not a good thing...

so i took it back and had it replaced, the guy told me that next time he would not replace it and to check everything was ok in the computer...he told me to reseat the mobo, which i have done, chech all the conections, which i have done, and check therewasnt anything loose which might be shorting the connections, which i have also done. i reconnected it all and it works fine for about an hour before conking out again....

i dont have the time or the money to fork out to have someone look at it, anyone any ideas what the problem could be?its a 350w psu and im only running a xp2000+ with 2hdd and 2dvd drives...and a old geforece 4 Ti4400....and the old one which ran for a year and a half no probs was only a 350w as well...

  spuds 19:05 11 Jul 2004

Do you have a surge protector installed!.

  wee eddie 19:12 11 Jul 2004

You say 2 HDDs and 2 DVD drives, the power consumption on start-up must be considerable.

Should more watts should be on your mind?

  Totally-braindead 19:18 11 Jul 2004

If you had this problem before and as you said you had to keep hitting the power button to get it to start it could be something as simple as the power switch being faulty, but it concerns me that the system blew the replacement power supply. Its possible the replacement supply was in fact faulty but its impossible to be sure. What operating system are you using, have you perhaps set some of the power settings to switch the PC off when not used for a length of time?

  Totally-braindead 19:24 11 Jul 2004

I don't think its the power supply you can check here click here but I ran my PC with 2 hard drives and a DVD and a CDRW drive for a couple of years with no probs at all. All power supplies are not the same though, it may say 350w and actually only supply say 275w. If you want to check whether it is the power supply I would disconnect 1 hard drive and one DVD drive and see if alls well then, if it is then you need a better power supply.

  SimianBenzoate 22:32 11 Jul 2004

not sure the amount of power is a problem... as i said it has been running fine for ages. i have also tried it with all peripherals disconnected so i only have to supply 1 dvd drive 1 hdd and a keyboard...

yes all my pc stuff is connected through a surge protector...

when i press the power button now the fans start up for about half a sec then die its not the power button...

i am using windows xp but no i have set all the power save settings off as my system used to be on 24/7 for weeks on end, with no problems i might add...

and i dont think it was a duff supply, as the replacement one also seens to have gone up the creek tho in less spectacular fashion...

so...any other ideas? i was wondering if it may be a shorting or earth problem, which is why the guy said to check the mobo was seated correctly and there wernt any screws or anything fallen into the case...but i dont know does the mobo need to be earthed? ie connected to the case in some way? or on the other hand, does it need NOT to be connected to the case, as the screws holding it to the case are obviously metal and they arnt insulated fron the case...

  kspatto 23:15 11 Jul 2004

disconnect all of your peripherals apart from the hard drive with the operating system and you video card unplug any sound cards modems etc disconnect all of the fans including your processor fan (it will be alright for a short period)turn on your PC if ok reconnect fans one at a time (turning PC off first)starting with you processor fan if still OK refit all other items until fault reoccurs this should pinpoint the problem if you have a fault with just your barebones system try a spare graphics card /hard drive if you have them if still faulty I would say your motherboard is fried(you could try removing it and checking that no parts of the board are damaged or shorting out at the mountings and no they should not touch the case they are normally fitted with plastic washers or are on a part of the board with no circuit
best of luck patto

  Giggle n' Bits 00:07 12 Jul 2004

fuses in the plugs for your pc ideally 5amp Not 13Amp which are usually defualt, maybe there is a bad wire in your house.

Then if it persists you need an Eleci Man to check you House over.

Does the Surge protector show a Red light for power on and Also a Green Light ? If the Green light is not lit but there then the surge protector had failed and not protecting the elec devices.

  stlucia 08:58 12 Jul 2004

The symptom you say happened in the past (having to press the button repeatedly to get it to power up) could have indicated a failing PSU, but it usually results in it being totally dead, not in it blowing up.

But since you say things have got exciting since you moved house, I would suggest you might need to get your house wiring checked -- at least the socket that you're using for your PC.

  SimianBenzoate 15:13 13 Jul 2004

ok i have now taken the mobo out of the case and tried it woth another supply and its been ok...up and running a full day now no problems...

so i'm guessing its something to do with shorting to the case?ive been trying to look up something on how to build your own pc on the web to make sure i've got the motherboard attached to the case correctly (i.e. should i have any sort of washers or anything on the screws, cos there never were any and it was working fine for ages before...) but my broadband seems to be knackered and i can hardly get any webpages does anyone have any hints? i have ordered a new case with a built in psu in case there was a problem with the case (i cant see how tho) and i just want to make sure i dont blow the psu in that too...

thanks for all your help so far...

  Totally-braindead 15:17 13 Jul 2004

The new case will come with all the screws, spacers and washers you likely to need, so I wouldn't worry about that.

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