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The truth is, no company wants the risk. All it takes is one of these recyclers to skimp out on basic drive formatting once and you get an article about how you

The truth is, no company wants the risk. All it takes is one of these recyclers to skimp out on basic drive formatting once and you get an article about how you can buy cheap macbooks and harvest them for data. Look at what happened with printers (HP's bottom line took a hit there), where you could buy a printer that had like 500,000 pages printed out of it for pennies.

brianwawok 10y ago
You can't basic drive format a SSD. You must shred or melt or explode to be safe.
- umanwizard 10y ago
  No, you can just issue a secure wipe command to the drive. If the firmware isn't buggy, your data will be unrecoverable.
- WalterBright 10y ago
  Just write over the data. If it really took 7 overwrites to erase data, then manufacturers would be selling 7T drives instead of 1T drives.
  - DanBC 10y ago
    You can't do that with SSDs because of wear leveling and weirdnesses with bad blocks. I think you can issue Secure Erase commands which do work.
    - WalterBright 10y ago
      You have a good point with the bad blocks. But just writing to all the free space on the disk should cover the wear leveling issue. I was mainly referring to the old wives' tale that data could be recovered unless it was overwritten 7 times. I've never heard of anyone recovering data that had been overwritten just once. I do understand, however, that there is no visual indication that the data has been erased, and that can be disconcerting. In that case, a ball peen hammer liberally applied should satisfy anyone.
      - brianwawok 10y ago
        > You have a good point with the bad blocks. But just writing to all the free space on the disk should cover the wear leveling issue. I don't think you have a good mental model of how a SSD works. let me try and help. Say you buy a SSD with 100 GB of space. It is really a 110 GB or 120 GB drive. You can only use 100 GB of it. During use, the drive will often "see" a bad sector, and remap it on the fly to one of the spare sectors it has on the device. When doing this - it does not wipe or do anything fancy to that "Bad" sector. So over time, small chunks of data get left behind in "Bad" sectors. You can format every single byte of visible space, but that will not touch "bad" sectors. Your format would only hit the 100 GB of space, it would totally ignore the 10 or 20 GB of spare or bad capacity. So if someone gets your freshly wiped SSD, they can dig up all of the bad sectors and see what is there. Maybe nothing, maybe a part of a file that has your production credentials. The police and NSA have tools to do this fairly automatically. I suspect organized crime would as well. Just writing some 0s to a SSD is NOT a safe way to wipe it.
      - WrtCdEvrydy 10y ago
        > old wives' tale that data could be recovered unless it was overwritten 7 times. https://www.lifewire.com/dod-5220-22-m-2625856 https://www.lifewire.com/dod-5220-22-m-2625856 This is the spec where people come up with. The idea is that you write a 0 pass, a 1 pass, and then a binary switch (3-pass). People have taken it to extremes with 5 pass and 7 pass BS. Honestly, doing 0's over the drive once is probably sufficient as long as you get every single byte.
        WalterBright 10y ago
        I read about that 7x stuff back in the 80's. As I recall, it was based on the idea that you could look at the disk with an electron microscope or something and it could pick up echos of the previous data. If this actually worked, data recovery companies would make a mint recovering overwritten files. But I've never heard of anyone advertising such or ever accomplishing it.
        WrtCdEvrydy 10y ago

brianwawok 10y ago

You can't basic drive format a SSD. You must shred or melt or explode to be safe.

umanwizard 10y ago
No, you can just issue a secure wipe command to the drive. If the firmware isn't buggy, your data will be unrecoverable.
WalterBright 10y ago
Just write over the data. If it really took 7 overwrites to erase data, then manufacturers would be selling 7T drives instead of 1T drives.
- DanBC 10y ago
  You can't do that with SSDs because of wear leveling and weirdnesses with bad blocks. I think you can issue Secure Erase commands which do work.
  - WalterBright 10y ago
    You have a good point with the bad blocks. But just writing to all the free space on the disk should cover the wear leveling issue. I was mainly referring to the old wives' tale that data could be recovered unless it was overwritten 7 times. I've never heard of anyone recovering data that had been overwritten just once. I do understand, however, that there is no visual indication that the data has been erased, and that can be disconcerting. In that case, a ball peen hammer liberally applied should satisfy anyone.
    - brianwawok 10y ago
      > You have a good point with the bad blocks. But just writing to all the free space on the disk should cover the wear leveling issue. I don't think you have a good mental model of how a SSD works. let me try and help. Say you buy a SSD with 100 GB of space. It is really a 110 GB or 120 GB drive. You can only use 100 GB of it. During use, the drive will often "see" a bad sector, and remap it on the fly to one of the spare sectors it has on the device. When doing this - it does not wipe or do anything fancy to that "Bad" sector. So over time, small chunks of data get left behind in "Bad" sectors. You can format every single byte of visible space, but that will not touch "bad" sectors. Your format would only hit the 100 GB of space, it would totally ignore the 10 or 20 GB of spare or bad capacity. So if someone gets your freshly wiped SSD, they can dig up all of the bad sectors and see what is there. Maybe nothing, maybe a part of a file that has your production credentials. The police and NSA have tools to do this fairly automatically. I suspect organized crime would as well. Just writing some 0s to a SSD is NOT a safe way to wipe it.
    - WrtCdEvrydy 10y ago
      > old wives' tale that data could be recovered unless it was overwritten 7 times. https://www.lifewire.com/dod-5220-22-m-2625856 https://www.lifewire.com/dod-5220-22-m-2625856 This is the spec where people come up with. The idea is that you write a 0 pass, a 1 pass, and then a binary switch (3-pass). People have taken it to extremes with 5 pass and 7 pass BS. Honestly, doing 0's over the drive once is probably sufficient as long as you get every single byte.
      - WalterBright 10y ago
        I read about that 7x stuff back in the 80's. As I recall, it was based on the idea that you could look at the disk with an electron microscope or something and it could pick up echos of the previous data. If this actually worked, data recovery companies would make a mint recovering overwritten files. But I've never heard of anyone advertising such or ever accomplishing it.
        WrtCdEvrydy 10y ago