Hard drive platters

Originally Posted by harsas

What about running a powerful magnet over the platter surface? I was told many years ago that this was fatal for a drive but have never actually tried it. Still, I have always been curious...

You would need a degausser with a high enough oersteds (Oe) rating in relation to the drive you are trying to degauss. The higher the capacity the drive and the newer it is, the higher the rating would be needed. Degaussing is completely ineffective against solid state drives however as they are not magnetically storing data.