One more late comment: Tossing 1.5 TB hard disks for nothing wouldn't make me feel too happy either. To zero out data is far better than "formatting" for sure. It should not be possible to restore anything without disassembling the drive. Still, there are companies out there offering data recovery, probably for less than MI6 would ask for. :-)
If my concept of professional data recovery is about right, the trick is to sniff for tiny magnetic patterns slightly off the "regular" track, a HDD head would write. The more secure mechanisms usually don't just zero out data x times, but rather write pseudo-random data patterns. This makes it very unlikely, that anything left on the drive contains something meaningful.
Well, as long, as you ebay account isn't Rockall Design ltd ...
One more late comment: Tossing 1.5 TB hard disks for nothing wouldn't make me feel too happy either. To zero out data is far better than "formatting" for sure. It should not be possible to restore anything without disassembling the drive. Still, there are companies out there offering data recovery, probably for less than MI6 would ask for. :-)
If my concept of professional data recovery is about right, the trick is to sniff for tiny magnetic patterns slightly off the "regular" track, a HDD head would write. The more secure mechanisms usually don't just zero out data x times, but rather write pseudo-random data patterns. This makes it very unlikely, that anything left on the drive contains something meaningful.
Well, as long, as you ebay account isn't Rockall Design ltd ...