Hey guys, there's something that's been worrying me for quite some time now and I can't rest before I'm assured I'm safe.
A week ago when I was building my new PC (from scratch) I flicked the VAC switch on the PSU down from 230v to 130v and after switching on the new pc there was 3 loud bangs accompanied by red sparks. I immediately removed the power cable and about 5 minutes later I attempted a reboot, thank God the pc started with no problems and i've had no signs of defect (at all). Every connector is getting the exact right amount of voltage from the PSU and temperatures are excellent.
You just blew the voltage doubler circuit and likely damaged other things in there, i would advise against using it. Just because the PC boots doesnt mean that the PSU isnt pumping out dangerous levels of noise to the components.
Sparks arent a sign that a protection kicked in, its a sign something failed. Also, the OVP is on the output side, not the input side, it protects your system by shutting down the PSU if the voltage on one of the output rails gets too high.
If a protection kicks in, the PSU shuts down and dumps excess power to ground if it needs to, it would NEVER intentionally generate sparks, one, they are inefficient, two, they are dangerous, your local tech doesnt have a clue what he is talking about.
It wasnt that there was too little voltage coming it, its that it thought there was half as much coming in as really was, that switch engages a voltage doubler circuit to step 115V up to 230V, when its set to 230V the input passes straight through, but if you are running on 230V and you set it to 120V, it still steps it up but now its got 460V not the 230V it was expecting, and nothing in there is rated nearly that high.
The voltage levels look good, but that is the DC level, there may be high frequency AC ripple in there that goes way out of ATX spec that you cannot see if something else got damaged when it blew. Any time a PSU gets damaged, it really should be replaced because there is no way to know just how extensive the damage was.