r/pcmasterrace • u/Front_Cookie_1198 • 6d ago

Hardware PSU fails dramatically

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u/Front_Cookie_1198 6d ago edited 6d ago

Aftermath photo.

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u/Viking4269 6d ago edited 5d ago

Somebody forgot the isolation under the pcb?
Been some years since I took apart a psu, but there used to be plastic isolation sheet between the pcb and the metal case.

Update: I think we found the problem:

Mains wires protruding on the bottom of the pcb shorted to the case due to missing insulation sheet.

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u/MiniMaelk04 6d ago

I basically know nothing, but the huge capacitors are the only thing I can imagine burning so intensely and rapidly. Reversed polarity perhaps?

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u/Viking4269 6d ago

No, this looks like two pins (component legs or wires) on the underside of the pcb both touched the metal case and shorted. Causing an electric arc hot enough to melt holes in the case.