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I've just re-cased my computer. I got the new case free and thought I'd be able to swap everything over myself but apparently I've done something wrong. I'm OK with components generally but wasn't totally confident about doing this.

So, my question is, when setting up a new PC or moving old components into a new case, what could I have done which causes the power cable plug to short/fuse when I plug it in?.

Is this likely to be an issue with the cables from my PSU, or could it be the internal case connectors?

What steps would you take to diagnose the problem? I'd rather not start again if I don't have to...!

Thanks in advance,

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What do you mean by "causes the power cable plug to short/fuse when I plug it in". Please describe what you see, what you hear and what you feel and what you do at the time. – Eroen Apr 13 '12 at 22:50
I plug the cable in; it goes "pop"; computer does nothing and the cable becomes unusable. Second cable I tried, same thing, but I also managed to turn off all the upstairs sockets in the house. I presume therefore that I've "fused", i.e. popped the fuse, on the power cables in question. – dunc Apr 13 '12 at 22:53
You really want us to play electrician over the Internet with your life hanging in the balance? If you're still alive, seek professional help for this problem before the premise of this statement changes. – Kyle Jones Apr 13 '12 at 23:03
That's possibly a mildly dramatic sentiment, though I appreciate your concern anyway. – dunc Apr 13 '12 at 23:22
rip PSU out, try again. Still a myth to me how you manage to break the power cables, doesn't your house have a fusebox? – Baarn Apr 13 '12 at 23:39

The first step I would try is to disconnect all of the power connections from the motherboard and the drives. I would then connect the power to the power supply and if it still shorts out or fuses then you have a bad power supply. If the power supply does not short out or fuse then I would remove the motherboard from the case and make sure that there are no mounting post coming in contact with any of the solider points or traces on the motherboard. Then I would get the manual for the motherboard and make sure all of the power connects from the power supply to the motherboard are connected properly. Then I would test again to make sure that the power supply is not sorting out or fuses. Then I would reconnect the power to the drive and test the power supply again.

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That and a common one is for you to put in a slot cover badly and have the slot cover short against something on the motherboard. Plug in, turn on, pop and nothing else happens. – Blackbeagle Apr 14 '12 at 2:59

The power supply should be insulated from, well everything, and moving it shouldn't cause a short. Replacing the PSU is the first port of call - Its the only component on a PC that deals with mains -you can get a cheap one to test. Also try replacing the fuses on the power cable once you have done this.

I can see one way this would happen - some cheap PSUs are designed in a rather shoddy manner and occasionally have heatsinks that are live (bad!!!), and separated from the case by a blob of silicon putty (worse!!!!!!!), if this putty somehow came off, and touched the case, the grounding of the PSU (its case) would be at high voltage, and pop goes the fuse.

Change the PSU. If its under warranty, RMA it, else throw it out. Its not worth fixing and risking your equipment or personal safety

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