The red switch on the psu

I just found out what that does, it makes the psu make a flash of blueish, greenish light & a electrical smell. Here’s how I found out, my brother thought that the red switch was the reason my desktop wasn’t booting, & that it wasn’t the right direction. (was unplugged BTW) So he switched it to 255V from 115V (I’m North America) & tried to turn it on. Of course that didn’t work, so he went investigating. Once he figured out it was unplugged, he plugged it in, & then powered it on. It work for like 1-2 seconds before… BOOM! There goes a flash of light from the psu, & a electrical like smell coming from the psu. Any clue how I’d go about seeing what is fired, and what isn’t? I know the psu is gone, because it doesn’t even power on. However when I plug in a different psu, it starts, I can hear the two hdds spinning, the fan above the heat sink starts, however I can’t see anything on my monitor. I do have a dedicated card (NOT powered by the psu directly). any idea on what to do?

Probably multiple components are broken. I would take a guess that replacing the motherboard may help.

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yep, I was afraid of that, dang :cry:

Theres a reason this switch is TINY and RED! :wink:
You found out the hard way…

Your hardware is probably broken. I’d try to boot the cpu and ram in another mainboard.
But please don’t use the burned PSU again. Just throw it into the garbage.


I already have, it no longer works, so y keep it.

I’d replace the PSU and hope that nothing else got fried. If the surge made it to the MB your entire computer is probably trash.

“Cant see on my monitor”

This is where BIOS beep codes come into play…
Most systems, if they are running in some way, but even say the video card is toast or missing, provided the cpu and memory works - will try going through the bios startup and generally throw a sequence of beeps. The sequence can then be decoded based on what bios manufacturer is onboard, some sequence indicating progress, activity from mobo, other sequences indicating peripherals (videocard) not detected. Its possible the videocard is toast while the mobo is fine.

No beeps at all - just power to the harddrives and fans - and its likely memory and or cpu are shot, or if lucky, just the motherboard is shot and sacrificed itself before burning out the memory or cpu (like the consoles on Federation Starships that explode and injure operators, but dont damage the video or touchpad inputs)

And… condolences…

You say you can’t see on your monitor - is your monitor just a solid black display? Or is it not even acknowledging any signal at all?

My father always said “DO NOT TOUCH THAT BUTTON. NEVER. EVER”. I never did. I can only imagine…

Imo, everything that doesn’t have fuses is gone. The motherboard, hard drives, etc. I may be wrong.

As to the fans, they’re just a mere motor so a bit of high current wouldn’t damage them.

Not acknowledging a signal at all.

Maybe the control board on the hard drives, but the data may be recovered.

You’d be surprised

I really, really hope so.


I think the mainboard and drives died. If you’re lucky the cpu, vga and ram is fine.
The PSU is obviously broken.

If only the harddrives and fans turn, mostly the mainboard died.
Try to get a new one and test the hardware bit by bit. Good Luck! :smile:

You might get lucky and it’s only the PSU. providing 110 when it’s expecting 220 isn’t as bad as providing 220 when it’s expecting 110. In the future don’t even buy PSU’s with a switch. Our school learnt the hard way with that one.

Yeah, wide range input PSUs should be a standard by now.

It was provided 225 when it expected 115.

North America does 115, Europe does 225, so this statement would be wrong. Seeing as it couldn’t have been provided 225.

According to you, it was provided 225.

I said the switch was flipped to 225.

Nevermind, not gonna explain it.

He’s located in 'murica -> 115V. The PSU was accidentally flipped to 225V (thus wrong).
The other way around would’ve been even worse.

That said it was provided 115V while it expected 225V.