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As per the title, would these magnets

Magnet Image

be enough to damage a portable hard drive such as this Seagate GoFlex

HDD Image

if left next to each other for longer than, say, 20 minutes?

Thankfully, this is all hypothetical at this point as I have kept them apart to date and my question comes to mind if the two fell on top of one another whilst in a backpack or bag.

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marked as duplicate by Moab, fixer1234, Ben N, Oliver Salzburg Feb 16 at 21:04

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

It you throw them fast enough... – woliveirajr Feb 15 at 18:13
I don't think so. – Moab Feb 15 at 22:46… – Moab Feb 15 at 22:49
We cant tell from the image how strong the magnets are. – Jonas Dralle Feb 16 at 20:12
But arent there already super strong magnets build into the harddrive itself? – Jonas Dralle Feb 16 at 20:12
up vote 34 down vote accepted

Considering the drive itself contains a magnet that I would expect to be far stronger than these are, I would doubt there to be any issues from them coming into contact. It's largely a myth that hard drives are easily wiped by a magnet (VHS, tapes and floppy media are far more likely to). In fact, a test was done here involving huge neodymium magnets, far more powerful than most magnets you will have, which caused zero data loss at all (more of a chance of mechanically damaging the drive due to the power of them if they'd been closer to the read heads).

I wouldn't state it's impossible for some form of damage to occur, but it's very unlikely. Don't worry too much about it, but keep them separate if you can.

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Not to mention, Harddisks are encased in a metal casing which essentially are farahday cages. – LPChip Feb 15 at 8:23
More commonly spelled Faraday cage. – Scott Feb 15 at 10:06
I thought a faraday cage (which is mesh) is distinct from a simple plate of ferromagnetic material - which acts as shielding? – Journeyman Geek Feb 15 at 10:31
Should be noted that the powerful magnets inside a hard drive are actually to control the actuator arm and not the read/write head itself (which is an electromagnet that's not powered when not in use). Also, just the fact that there's magnets inside doesn't mean external magnets of equal strength will have no effect - the orientation of the field could make a big difference. It just happens that in this case these magnets are too weak to do much. – Bob Feb 15 at 13:21

If you want to damage a harddrive with a magnet, the drive needs to be running and busy writing/reading stuff. And even then you need a damn powerful magnet.

I once disabled a harddrive with a 10x10x15 big magnet, and I believe it's more damaged because the internal mechanics got twisted/damaged during reading writing. I suspect a head crash

All in all you need a pretty big magnet.

Want a magnet that is guaranteed to destroy a hard drive — or for that matter, a CD/DVD drive? You need something like this 2-inch N52 neodymium disc magnet that has a pull force of approximately 450 lbs. Get your hand clamped between this and a piece of magnetic metal, and you could lose your hand. This won’t just erase the hard drive, it will wreak it, along with the CD/DVD drive and any fans.

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