Trouble installing new PSU - blue sparks, bangs, help!

[Xiahou]

Hopefully the power supply didn't destroy any components other than itself.

[sapi]

I was thinking the same thing. If you accidentally hit the wrong thing.... :(

[caravel]

The PSU is indeed "toast". There are some large transistors on the main board, if you hear a bang it's one of those. Bigger bangs with blue smoke and a horrible smell indicate that one of the larger condensors have "popped". In my experience PC World are a bunch of ....... You may have difficulty getting an exchange/refund, though hopefully not. What brand of PSU was it?

As the problem arose after putting the case lid back on, I thought I might have loosened a wire or something pushing the thing in. In particular, the wire connecting the front power button to the innards might have come loose, so I pressed that in. I also switch the amp on lead from 5A to 13A (as the new PSU says 500W 8A). I switched on the machine and there was a nasty blue flash from within the PSU and a small bang. Whists of smoke and pungent smell.

You say you may have loosened something. Connecting the power, hdd, speaker, etc jumpers to wrong pins can be disastrous. That could have been the cause, also I'm not sure why you switched the fuse, but I doubt that had anything to do with it. Once a PSU or the kettle lead fuse has blown though, it is inadvisable to try and connect it again. Hopefully your motherboard hasn't been damaged. Before you reconnect your old PSU you need to be absolutely certain that everything is connected ok inside, if you're unsure of what you're doing, you should defininitely get help.

[econ21]

Thanks. I've put the old PSU back in and everything works fine, so the new one going bang thankfully does not seem to have fried my computer.

I did worry I'd connected things wrongly, but I've just plugged the connectors in the same way with the two PSUs, so it's not clear how I can successfully install the old PSU twice and yet blow up the new one. (I suppose the new one might need connecting in a different way, but this wasn't clear from the instructions or physical appearance of the thing).

BTW, the new PSU is a jeantech 500W - it's the only brand PCWorld sell, although I bought the most powerful (for the bigger...err...bang )

I think I'll try to get a refund from PCWorld and make an appointment with them to install a new one.

[sapi]

Good idea.

You don't want to get literal bang for buck