Why would an internal hard drive suddenly short circuit when attached on another PC?

Question

The hard drive is a main drive in a pc I was troubleshooting. It was working fine and was able to boot Windows XP on the original pc. When I pulled it out and attached it (via USB + external power) to a second pc, I saw spark on the hard drive board near the power connector.

Why would it suddenly short circuit like this? Is there any chance to recover data from that drive?

I haven't attached the drive back into the original pc yet.

UPDATE: I plugged the drive back into its original PC and it works without any problems. Is it possible that it is the electricity at home that caused the short circuit? I'm on a city thats far away from where the original PC runs.

Answer 1

Did you plug in the drive's power connector while the host PC was on? If so, that's not to be encouraged anyway.

The spark might just have been due to the drive startup current punching through some grime on the connector - especially if you were plugging the drive with the power on.

If, however, the spark occurred when you switched on the power then that's another thing - although I have seen this occur when a drive (Molex) power connector has been attached the wrong way round - it's surprisingly easy to do this with some of the 'softer' plastic plugs - and unfortunately this usually kills the drive. I managed to do this a few weeks back with a SATA-Molex power adaptor - note the fried chip in the pic:

The only way to find out if anything's damaged is to fire up the drive, having checked the power connector orientation and looked for visual damage (and burnt smells/fried chips) on the drive circuit board first.

Answer 2

I can't determine to health of your HD, without knowing its behavior when plugged in. However short circuits will usually just effect the printed circuit board, therefore replacing the board is a possible solution to fix your HD. The drive might come back on after a while or might not.

I would say the best way to fix this HD is to check out myharddrivedied.com. It is an amazing site with all the knowledge you'll ever need to know about fixing HDs (online material is free). The site also has a podcast to listen. Enjoy your adventure of data recovery.

Side note: Bad power supplies and heat are major killers for any HDs. Good power supplies for HDs range about $80+, anything less is a chance of risking your HD to bad power.

Answer 3

There is a chance of recovering the data (assuming that you fried the HDD controller), but before I get into that, try to see if the HDD works. It may have "fried" for a few reasons:

• internal short circuit on the HDD board itself
• floating voltage on the second computer's PSU
• short circuit on the second computer's PSU

I'd assume the issue lies with the second computer's power supply, so you should investigate that before using that machine anymore. Get a multimeter, and make sure the voltage outputs from the PSU are good. Regardless, what's done is done, so you should test the hard drive on the original computer and see if you can make it spin.

If that doesn't work, your only choice (aside from paying huge fees to data recovery specialists) is to go a computer parts retailer and try to find your exact same hard drive (go to eBay if you can't). Then you will have to swap the controller boards, and hope that it works. I have seen this work in the past, so it's not impossible, but it also assumes that the drive heads and servo motors are still working correctly.

I recommend this before going to a data recovery specialist, first because it will be significantly cheaper, and second because you still have that option if it wasn't the controller (you're not touching the platters).