[chris (OP)]

I was contemplating giving one of my children my old laptop because hers is falling apart.

My one uses SSD storage. But because I've used it at the hospital and for clinical work, while there should be no personal data there, I wanted to erase it with a data over-write to be absolutely certain.

But then I was warned that this can damage an SSD storage device.

My questions are:

1) Is data over-writing necessary for an SSD storage system
2) How can a single over-write possibly damage / prematurely age the device more than routine use does anyway?
3) Is a multiple pass overwrite unnecessary on an SSD.
4) If I cannot over-write it, how should I make the device "data safe" before passing it to a third party?

[Peter11]

Well your giving it away to someone you trust so I wouldn't worry.The only way to hide all data is to encrypt the drive before throwing it away and toss the key to the encription
There are secure erase utilities available some by the drive suppliers themselves I recomend you look for a SSD secure wipe utility

[vhfpmr]

The only way to hide all data is to encrypt the drive before throwing it away and toss the key to the encription

Won't that just make the space unusable by anyone else?

[Peter11]

That only applies to SSDs you are trashing.In your case you are looking for a SSD secure wipe utility - it can be done on some PCs in the bios.It can also be done using the command line if you are a advanced user which I will not go into you can look it up which will be the Diskpart command.Ok I will tell you.Type cmd run as admin type diskpart type list disk select the disk number type clean then type exit done.
Oh its not admin its the full word administrator I don't know why I shorten it if you type admin it won't work of course enter after each entry.
I forget people don't know this stuff anymore and I assume most do.

[evan_au]

There are legends about spooks who could read the data previously stored on a hard-disk, by reading the stray data "between" the tracks.
- Hence the idea of overwriting every sector with random data, multiple times, approaching from multiple directions, to also overwrite the "stray" data between the tracks.

I do not know whether the spook art has progressed to the point of sawing open the chips and counting the electrons on an EEPROM NAND gate, and determining whether that cell previously contained a 0, 1, 2, 3, 4, 5, 6 or 7 before it was overwritten
- I am sure that spooks would attempt this procedure if they had the opportunity to read the guidance software of a missile - before it has been erased.

Overwriting the every sector multiple times will cause wear on the SSD - but apparently they are rated at 100,000 write cycles, so not too much wear.
- As sectors wear out, they are put on a "do not use" list, and the result is that the disk capacity slowly decreases (and you might lose an occasional file which suddenly couldn't be recovered)
- I suggest that for an SSD, it is sufficient to use a tool which overwrites every sector once

See (other brands are available): https://www.kingston.com/en/blog/pc-performance/nand-flash-technology-and-ssd

[chris (OP)]

There are legends about spooks who could read the data previously stored on a hard-disk, by reading the stray data "between" the tracks.
- Hence the idea of overwriting every sector with random data, multiple times, approaching from multiple directions, to also overwrite the "stray" data between the tracks.

I do not know whether the spook art has progressed to the point of sawing open the chips and counting the electrons on an EEPROM NAND gate, and determining whether that cell previously contained a 0, 1, 2, 3, 4, 5, 6 or 7 before it was overwritten
- I am sure that spooks would attempt this procedure if they had the opportunity to read the guidance software of a missile - before it has been erased.

Overwriting the every sector multiple times will cause wear on the SSD - but apparently they are rated at 100,000 write cycles, so not too much wear.
- As sectors wear out, they are put on a "do not use" list, and the result is that the disk capacity slowly decreases (and you might lose an occasional file which suddenly couldn't be recovered)
- I suggest that for an SSD, it is sufficient to use a tool which overwrites every sector once

See (other brands are available): https://www.kingston.com/en/blog/pc-performance/nand-flash-technology-and-ssd

That was my view, and what I decided to do; a write-once is probably sufficient.

[Bored chemist]

But because I've used it at the hospital and for clinical work, while there should be no personal data there, I wanted to erase it with a data over-write to be absolutely certain.

There's a duty on you to take reasonable care to delete the data.
The consensus here (and I agree with it too) is that overwriting once should be enough.

I think that would meet the legal definition of "reasonable".