ATA Secure Erase method

What does the ATA Secure Erase enhanced actually do when erasing a WD hard drive, compared to the “normal” ATA Secure Erase?

I can’t find a definitive answer online, not even on the WD website.

SUPPOSEDLY - It regenerates the ATA encryption keys as well as erasing the disk. This means that even if there is any data remaining on the platters it can no longer be read

Ata secure erase not only erases the visible sectors of the drive but also clears out the spares and tests everything for usability. You may see the reallocated sector count change after a secure erase and the pending sectors should always be reset to zero.

However if hdparm reports the same time for both methods:


we should conclude that:

  • This disk performs a full data overwrite (that’s the only reason why it would take almost three hours).
  • The “secure erase” and “enhanced secure erase” for that disk are probably identical (but it might spin the keys as well as overwriting)

That said: If enhanced secure erase is available, take it

Once a secure erase has been done the drive is effectively unreadable (Peter Gutmann’s seminal 1990 work with atomic force microscopes was done on 10MB drives, not 10TB ones and he doesn’t believe it’s possible to replicate anymore), however if you’re paranoid then toss the drive into a shredder.

Thank you for replying. :slightly_smiling_face:

Most people are probably unaware of the built-in secure erase that exists in their hard drive (or SSD).