[urrl5201]

If I am to sell my 17" how can I erase sensitive info like bank accounts beyond recovery? There is PC software out there. Is there Mac software also?

[acadian]

You have to write 0's to the drive, I beleive there ia a knowledge base article on this and requires booting into factory mode or something.

[stevesnj]

If you have an OS 9 disk or someone you know has one there is a zero option in the Disk Utility, I use it when I re-install OS X but it take a LLLOOONNNGGG time to zero a drive, it took 3.5 hours to zero my 40gb drive. But it's worth it to get rid of any problem whatsoever and there is no worry of a stray file lying around that could give you a problem that a standard format failed to re-organize.

[Tomster]

You can try the shareware Shredder - look for it at versiontracker. Or, if you want to save some bucks, fire up the terminal and use dd with if=/dev/zero. man dd, for specifics. Please use caution because a typo can result in writing zeros over your entire drive.

[Karim]

Originally posted by stevesnj:
If you have an OS 9 disk or someone you know has one there is a zero option in the Disk Utility, I use it when I re-install OS X but it take a LLLOOONNNGGG time to zero a drive, it took 3.5 hours to zero my 40gb drive. But it's worth it to get rid of any problem whatsoever and there is no worry of a stray file lying around that could give you a problem that a standard format failed to re-organize.

Only problem with this solutions is that 17" Powerbooks won't boot into OS9.

[gatorparrots]

How to erase the HD beyond recovery?

* Open up your PowerBook and remove your drive (instructions here: http://www.xlr8yourmac.com/powerbook...d_upgrade.html)
* Unscrew the metal casing around the hard disk
* Forcibly pull the servos off of the drive with a pair of pliers
* Smash the drive repeatedly with a ball peen hammer
* Smash the drive with a singular, well-placed sledge hammer blow (with finality)
* Gather all the pieces into a pile
* Pour hydrochloric acid on the pile of pieces
* Douse with gasoline (or airplane fuel, if accessible)
* Set alight

Following these instructions should give even the NSA fits trying to recover data off of the drive.

[tooki]

Actually, they sometimes shred the drive (like, physically, into little pieces).

tooki

[The Placid Casual]

Although I hate Norton (And don't use the stuff myself), didn't a part of the 'System Utilities' for OS X suite perform the function?

[Phanguye]

Originally posted by gatorparrots:
* Open up your PowerBook and remove your drive (instructions here: http://www.xlr8yourmac.com/powerbook...d_upgrade.html)
* Unscrew the metal casing around the hard disk
* Forcibly pull the servos off of the drive with a pair of pliers
* Smash the drive repeatedly with a ball peen hammer
* Smash the drive with a singular, well-placed sledge hammer blow (with finality)
* Gather all the pieces into a pile
* Pour hydrochloric acid on the pile of pieces
* Douse with gasoline (or airplane fuel, if accessible)
* Set alight

Following these instructions should give even the NSA fits trying to recover data off of the drive.

1. Write 1's
2. Write random bits
3. Write 0's
4. Repeat 1-3
5. Open HD
6. Break platters into peices
7. bury peices in seperate locations

that is what i do at least

[mosch]

If you want to rest assured that nobody is going to be able to ever recover anything, boot from the recovery cd, open the terminal, then run 'df' and look for the filesystem that you want to wipe out. The output will look like this:

Code:
Filesystem              512-blocks     Used    Avail Capacity  Mounted on
/dev/disk0s9             117197648 44959672 71725976    38%    /
devfs                          193      193        0   100%    /dev
fdesc                            2        2        0   100%    /dev
...

In this case, the drive I'd need to wipe out is /dev/disk0s6. So in terminal, type:

Code:
dd if=/dev/random of=/dev/disk0s6 bs=8192

that command copies random data over the entirety of that disk, 8k at a time, thus thoroughly decimating anything you had on your disk. Even the most paranoid tin-foil hat wearer would agree that alternating passes of /dev/random and /dev/zero will leave your drive in such a state that it is safe to sell with no hint of concern, ever.

[fldsfslmn]

the u.s. department of defence standard is 7 passes over the HD. normally these passes alternate between two sequences of characters or write random garbage.

[gatorparrots]

By the time that much time is wasted writing ones and zeros, it would have been much cheaper and faster to physically destroy the drive and replace it with a new one.

[Jacket]

Originally posted by gatorparrots:
By the time that much time is wasted writing ones and zeros, it would have been much cheaper and faster to physically destroy the drive and replace it with a new one.

from quickly reading this, i'd agree. harddries aren't that expensive anymore that you can't destroy the existing drive and replace with a new one... if you're selling the thing, just add the cost of the new hard drive to the total you'll charge, (may a little less) and live worry free.

[fldsfslmn]

data (though often fragmentary) can be restored from "smashed" hard drives -- there are a few people around who can actually perform this kind of HD surgery.

that is why the DoD standard is 7 overwrites, not necessary in most cases, but better than just smashing the platters alone.

[icruise]

Never actually used this, but:

http://freshlysqueezedsoftware.com/products/iwipe/

[Vond]

Originally posted by fldsfslmn:
data (though often fragmentary) can be restored from "smashed" hard drives -- there are a few people around who can actually perform this kind of HD surgery.

that is why the DoD standard is 7 overwrites, not necessary in most cases, but better than just smashing the platters alone.

They also have special industrial "shredders" which you can put HDD platters through. They may go as far now as grinding former Top Secret platters into dust, I dunno. What I do know is that they can recover almost anything which leaves the drive intact. But I doubt the original poster is planning to sell his laptop to the NSA.

[vmarks]

Originally posted by tooki:
Actually, they sometimes shred the drive (like, physically, into little pieces).

tooki

In the case of drives with glass platters, a few good drops from height works.

In the case of drives with metal platters, welding the platters to each other does the trick nicely.

[ae86_16v]

The NSA is suppose to be able to recover things even after it's been smashed...or at least that is what I heard.

Even with the reformats, in the atomic level, there are still some information that is left behind. The NSA claims to be able to pick up those individual atoms to restore the data.

Or at least that is what I HEARD....

[Tomster]

There have been some interesting solutions presented to the person who originated this thread. Realistically, though, all this individual has to do overwrite the sensitive files using any of the means previously mentioned. Then just do a reformat and installation/update of Jaguar. Is there data on it that can still be read? Of course. But think of this: he is selling the computer. Now if you just bought a 17" Powerbook, what would you do first? Search the drive, sector by sector for information? Or would you rather hook the thing up in target disk mode, copy over the partitons on your current rig, get everything up and going, and see just how fast and cool the Powerbook is?

[iohead]

Originally posted by urrl5201:
If I am to sell my 17" how can I erase sensitive info like bank accounts beyond recovery? There is PC software out there. Is there Mac software also?

You can use the *free* GNU command line utility called "shred" (it's part of the "fileutils" package) to delete your sensitive files securely.

If you use Fink, say, it should be trivial to install fileutils:

sudo apt-get install fileutils

If you don't have Fink, you could download fileutils from a GNU mirror and compile either the entire package, or just the shred utility.

If you don't want to do any of these things, here is a pre-compiled version of GNU shred:

http://www.kernelthread.com/mac/binaries/shred.bz2

Once again, it's a command line utility - you would need to use the Terminal.

-A