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Free Geek organizations (I can't speak for others) have a comittment to destroying data on donated drives before they go out again. If you don't want to (or are not allowed to) trust that, then you can download a copy of DBAN and nuke your drives for a few hours (or days) before you donate them.

For most civilian uses, 'dd if=/dev/zero of=/dev/hdX' is sufficient (with today's drive density) to make the data on the drive effectively irrecoverable. --- but, if the NSA is after you for violating the Nuclear Secrets Act, all bets are off.

Why are you relying on sdelete instead of something like DBAN?

USB keys can be quite useful, even in small - think backup (PGP, SSH, etc) keyring, a convenient way of putting anti-malware software onto an infected computer that has been pulled off the network, etc. Despite having several multi-gigabyte flash drives, I keep a 32 meg drive around just for copying MBAM and friends onto infected machines for doing cleanups.

Have you tried DBAN? Works great for me.

As a Staples retail employee I can tell you that that would not "cost extremely little to implement." There would definitely have to be a charge, to offset the time an employee would have to be away from the sales floor while wiping a computer hard drive.

Uh, are you wiping the hard drive by using a tiny magnet and flipping all the bits by hand? Typically, you just go out and find your favorite drive wiper, spend five minutes getting it started and then walk away for a few hours.

Well even five minutes would cost ~$10 to do it. And don't forget the computer has to be removed from its box and put back neatly, which adds more time to the operation.

As a Staples retail employee I can tell you that that would not "cost extremely little to implement." There would definitely have to be a charge, to offset the time an employee would have to be away from the sales floor while wiping a computer hard drive.

Uh, are you wiping the hard drive by using a tiny magnet and flipping all the bits by hand? Typically, you just go out and find your favorite drive wiper, spend five minutes getting it started and then walk away for a few hours.

I've installed Windows 7 32-bit Pre-Pre-Release (build 7000 for inquiring minds) on my gaming machine and it works surprisingly well. Ventrilo took a bit of fiddling to work right, but other than that it worked better out of the box than XP Service Pack 3 does. It didn't need any extra drivers, although it did prompt me to update the Graphics card driver, which it happily did automatically.

Then the trouble started.

Since I had several firefox tabs open, I opted to put the computer into Hibernation for the night so I could continue with them this morning. It obliged surprisingly quickly and shut off the system power. Fans went off, case lights went off, and the USB devices lost power. The system was off. Off I Tell you!

I went to bed. While reading Paris in the 20th Century by Jules Verne, almost an hour after I had shut off the machine, quietly returned to life! I thought that some bump or vibration or some minuscule cosmic ray had activated the case button and quickly dismissed it as some one-off odd event. I went back to reading about Le Grande Entrepôt.

About a chapter later, I don't know how much time had passed, the beast roared back to life with the ferocity of all fans at one hundred percent and the squeal of the system speaker! Twice in one night was too much for coincidence. I put the machine into hibernation once again, unplugged the power supply and resigned myself that if it came back to life once more, I would call a priest for an exorcism. (which would be quite a phone call, considering that I do not frequent churches)

Tonight, I will be sleeping with a copy of dBaN by my side.

Reading a modern hard disk that's been written over with zeroes is not that simple, and would likely require very specialized, very precise hardware.

The historical problem with writing over with zeroes was that the amount of magnetic surface between tracks on the platter was fairly large. This space between tracks would keep a "ghost" of previous data should there be only zeroes written to the nearby tracks. Guttman's research and the DoD wiping method were designed to overwrite the track data and make sure that that "ghost data" would be wiped as well.

Modern disks have such narrow gaps between tracks that overwriting with zeroes is sufficient to stump any commercial data-recovery attempts. (See, e.g. The Great Zero Challenge).

The military takes more extreme measures with highly-classified data because there are ridiculously expensive and time-consuming methods that one could use to recover data that's been "merely" wiped. There are governments and organizations that have those resources that might be willing to expend them to get their hands on such data.

There are not criminal organizations that have or will expend the insane effort to recover the information that might be on an individual's drive. The cost-benefit just isn't there. An individual who boots something like DBAN and does a one-pass wipe of all zeroes across the entire disk is entirely safe from anyone who has less resources than a major government intelligence agency.

Reading a modern hard disk that's been written over with zeroes is not that simple, and would likely require very specialized, very precise hardware.

The historical problem with writing over with zeroes was that the amount of magnetic surface between tracks on the platter was fairly large. This space between tracks would keep a "ghost" of previous data should there be only zeroes written to the nearby tracks. Guttman's research and the DoD wiping method were designed to overwrite the track data and make sure that that "ghost data" would be wiped as well.

Modern disks have such narrow gaps between tracks that overwriting with zeroes is sufficient to stump any commercial data-recovery attempts. (See, e.g. The Great Zero Challenge).

The military takes more extreme measures with highly-classified data because there are ridiculously expensive and time-consuming methods that one could use to recover data that's been "merely" wiped. There are governments and organizations that have those resources that might be willing to expend them to get their hands on such data.

There are not criminal organizations that have or will expend the insane effort to recover the information that might be on an individual's drive. The cost-benefit just isn't there. An individual who boots something like DBAN and does a one-pass wipe of all zeroes across the entire disk is entirely safe from anyone who has less resources than a major government intelligence agency.

Revision3's Systm show had an episode that suggested some ways for destroying a hard drive yourself. They took the position that using a program like Boot'nNuke, which overwrites data 1-N times at your choosing, is sufficient to sanitize data without destroying the drive.

If you want to go the nuclear option, they demonstrated some favorites: mangling the platters in a vice, dremel or hand grinder, propane or cutting torch, melting it in thermite, etc.

A hospital I worked for once, when decommissioning old computers, would take the hard drive over to a drill press and put a couple holes through it. Nowadays I think they've bought a drive shredder.

Internal Server Error

Go here instead: dBan, Derrick's Boot and Nuke.

This recommendation from Which? magazine has incensed me today. They're reported as saying "It sounds extreme, but the only way to be 100% safe is to smash your hard drive into smithereens.". There's no need to do this if you use disk wiping software, which is probably even better than a hammer; as the BBC article points out. Darik's Boot And Nuke is perfect for this. It's environmentally criminal to be suggesting the best way to wipe a disk is to smash it.

Pete Boyd

and just use dBan, Derrick's Boot and Nuke.

Nothing beats an afternoon of watching dBan and a comfy chair. Beer or whisky optional.

It has limited access - until a larger drive needs to be installed, and the the old one ends up in the spare parts bin and eventually gets sold as surplus, and somebody gets it home and finds your medical records on it.

Standard policy almost everywhere I've worked has been "old disks that aren't being re-used internally get destroyed." And those that ARE getting re-used, don't get to be re-used until they are wiped clean with something like DBAN. Places that do sell off old equipment have also had the same requirement -- old disks get wiped.

Yeah, but can it survive DBAN? http://www.dban.org/

I bought a computer (by th' pound) that turned out to be the old web/mail server for a companyâ¦Âverified it on the wayback machine that i had it as it was when it was yanked off the web.. i had some contacts at another branch of the co, and they weren't interested in it back. Always keep a copy of http://www.dban.org/ around before anything goes out the door..

Learn it, know it. A very simple utility for wiping drives that you can run as a boot disk.

DBAN

A deleted file including an ISO can live on the hard drive forever in recoverable or partially recoverable form. Criminals routinely buy PCs from surplus and then re-sell the uninteresting ones in hopes of garnering some profit from deleted data - in many cases turning a profit just on the turnaround process. Security researchers do it also, to gain fame and credibility from pointing the finger of shame which leads to step 3: consulting profit! A PC that's been "quick formatted" and then had an OS installed on it still has considerable valuable data on the "blanked" space - and on the disk the valuable user data almost always occupies the same space on the disk in the space that would still be blank after an OS install, it would be easy to find. The correct course for personal data is some low level drive wiping program like DODWipe (a commercial application) or Darik's Boot and Nuke DBAN (free). These programs overwrite every byte on the disk they can access, but cannot overwrite blocks "marked bad" by the hard drive itself - which is a much lower risk because those blocks are almost never readable anyway. Just using the software is no panacea either. It has to be used correctly.

For a drive that may have had a credit application, job application or similar data on it (even just one) the risk is too great to take chances with. So:

1. It had better have had full disk encryption first. This is not the '70s. and !
2. Smelting, chipping, sandblasting, drilling or bending platters are preferable to wiping. Drilling and bending are not recommended as data can still be recovered with enough investment. The cost of fully audited destruction is negligible compared to the benefit.

Just handle that data as if it were a level 4 biohazard that would wipe out your company if it were released, and you'll have the general idea. Wiping before chipping or smelting, though, is just paranoid and should be left to the TLA and tinfoil hat types, and swiss banks where disclosure of data is a capital offense.

It's dumb, but not as dumb as your ideas.

Are you seeing the irony here yet?

I actually wouldn't worry too much about the hard drives. As long as you take some precautions like securely wiping them, with something like DBAN (which is free and incredibly, maybe dangerously, easy to use). You can wipe the drive using a large number of methods and to a number of different standards (including, oddly enough, the Canadian Mounties standard. Who knew!?). I wiped a bunch of computers that my Dad's company was going to donate using it, and it took a little while (depended on the computer and drive, but was anywhere between an hour and 4-5 hours), but it was easy and didn't require any babysitting once it got started. We wiped them to the DoD standard, which seemed good enough, though we could have gone further than that.

I'm always sure to securely wipe the data before handing it over. Darik's Boot and Nuke is a great tool for that. Run it overnight and you'll be good to go. It looks like some lawyers got ahold of them and they've stopped saying how well it destructs, but it's definitely up to the latest standards. They are also partly funded by a North American recycler

I'm always sure to securely wipe the data before handing it over. Darik's Boot and Nuke is a great tool for that. Run it overnight and you'll be good to go. It looks like some lawyers got ahold of them and they've stopped saying how well it destructs, but it's definitely up to the latest standards. They are also partly funded by a North American recycler