PSU keeps popping fuses.

markpbennett · 23 Jan 2012 at 17:21

hi,
i got my overclocked package back from OC after they replaced a recalled board. Fitted back into my PC...but when i tried to power up nothing. No Fans or anything...just a burning smell.

As there were no fan lights...i took it as the PSU had blown.

I bought a Antec 650w(EA) and fitted this....again no fans...one light was present on the mobo. So i unplugged the mobo power cable and plugged into a psu tester. when i switched on...the fuse in the plug blew and tripped my homes fuse also.

after this..it keeps blowing the fuse.

So i returned the PSU and got a replacement....exactly the same story!

can anyone advise? as i didnt think a dead mobo or even a short anywhere could cause a PSU to blow?!...twice?!

Thanks for your help!

Tealc · 23 Jan 2012 at 18:53

Did you try a different power lead for the PSU?

markpbennett · 23 Jan 2012 at 20:48

Tealc said:
Did you try a different power lead for the PSU?

hi, i tried my monitor cable ...it blew the fuse in that too!

IvanDobskey · 23 Jan 2012 at 20:55

New PSU time I suspect. Fingers crossed it hasn't nuked any of your components.

Reaper 392 · 23 Jan 2012 at 23:59

what fuses are you putting in the plug?

if the PSU was close to its maximum it would blow a 3A fuse because it draws more than 650W from the wall to provide 650W to the PC.

my only other idea is to try a different socket in the house

wazza300 · 24 Jan 2012 at 00:02

might be psu short inside thats blowing fuse at the plug? best to try another psu

markpbennett · 24 Jan 2012 at 08:19

Hi,
i tried both 5A and 13A with the new Antec....which blew.

I took this back and got a replacement. Fitted this....the "power-on" switch on my mobo was lit...but when i pushed the power on button(on the case) nothing happened..no fans or lights etc. So i unplugged the 24 pin power connector from the mobo and plugged this into a power supply tester to see what was coming through. This blew the fuse and tripped the circuit breaker in the house. No blows the fuse everytime i plug into the wall.

Last night i tested my old power supply using my monitor kettle cable...and the readings look good? So i reinstalled my old PSU. I get the "power off " light on the mobo...but nothing else.

Any advice on where to proceed?

I'm thinking it may be best to pass over to a local repair shop? As i dont have any spare components to start swapping in and out?

Im thinking the mobo should be okay....as im getting the "power off" switch light up? could this mean the processor or mem is screwed?

Tealc · 24 Jan 2012 at 08:29

I can't think of a reason why any component on the DC side of the PSU would cause the mains plug fuse to blow. The PSU should shut itself down if there were anything untoward going on, or at least it should do. I've accidentally shorted the 12v to ground when I was fiddling with LEDs a while back and the PSU just shut itself down. It takes something quite serious to blow fuses.

Sasahara · 24 Jan 2012 at 10:05

I'd test the new Antec with out installing it in the PC using the paperclip test and connect some case fans if you have any.

http://dodji.seketeli.com/downloads/shuttle-psu-paper-clip-test.pdf

http://www.youtube.com/watch?v=-Loqz-GAjcA

If that works maybe dismantle the PC and test it part by part.

1) Mobo, with CPU and ram only. (Graphic card if it has no onboard)

If you have a safe area to work in maybe do this outside of the case, Setting it on cardboard.

Then add additional parts if this is successful.

Reaper 392 · 24 Jan 2012 at 10:53

if its blowing 13A fuses my first thought is a short somewhere. see if you can eliminate the kettle cable by stealing one from another appliance. if you dont have another cable thats suitable in the house i'd be very surprised

markpbennett · 24 Jan 2012 at 11:16

Sasahara said:
I'd test the new Antec with out installing it in the PC using the paperclip test and connect some case fans if you have any.

http://dodji.seketeli.com/downloads/shuttle-psu-paper-clip-test.pdf

http://www.youtube.com/watch?v=-Loqz-GAjcA

If that works maybe dismantle the PC and test it part by part.

1) Mobo, with CPU and ram only. (Graphic card if it has no onboard)

If you have a safe area to work in maybe do this outside of the case, Setting it on cardboard.

Then add additional parts if this is successful.

I have a power supply tester...am I ok to just have that plugged (via 24 pin connector) into the psu, outside of the case? I did this with the first antec unit, to make sure it was ok, and the PG light litup for about 2 secs..then went out and the unit just blew fuses after than and the on/off switch on the back was stuck in the on position?!

My old psu(Ocz 600w) lights up +3.3v, -12v, +5vsb and +12v only. But the fan doesn't start straight away..it judders ..then starts to turn after a minute or so.

mmj_uk · 24 Jan 2012 at 13:16

So two PSU's have had problems with this replacement motherboard you received? have you tried the PSU's on another motherboard? it sounds like you've been sent a dud.