Windows 7: Leave No Trace: How to Completely Erase Your Hard...

How to Completely Erase Your Hard Drives, SSDs and Thumb Drives

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Even better: a cross cut shredder.

I understand that more identity theft takes place by dumpster diving than recovering from computer media.

However, I would never let a non-cleansed disk out of my control either.

My preferred method is a lighter and a trash can full of water.

Using the Clean All command (possibly a few times) on the drive should thoroughly wipe it spotless without having to use a 3rd party program to do it.

This is a good tutorial and will cover most cases. For the really paranoid, a nice hammer is best.

(Before I give an old system to Goodwill or some other charity, I run "Killdisk" and write zeroes over everything. That takes care of the casual snoops, and most of the not-so-casual ones as well.)

FWIW, even after running a Government approved clearing program the bad guys CAN get info from your storage systems - it is just a matter of how bad they want it. For US DoD storage that has been used for Top Secret, the only answer is acid.

I tend to pac rat my old drives.
Having said that and recently cleaned out the computer room, I have about 8 old drives going back a few years. They have no use, and I highly doubt there is anything important on any of them. But, before I trash them I'm going to trash them. Back of the axe on the chopping block..

I take them apart, keep the cool super strong magnets. Yank the platter out. Take the empty drive case to Goodwill that is partnered with Dell for electronics recycling. Mangle the platter with a sledgehammer.