Safe disposal or old computer/laptop

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Passport1

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Hi

Are there any companies or organisations in Dublin/Ireland to whom you can give old computer/laptop too and they will recycle it safely in terms of reformatting it for re-usage or for safe disposal off so that no one would be able to get the data off it

Thanks
 
Take out the Hard Drive and drill a hole through them. You need to drill a hole through the platter.

You can also overwrite. But if you have to ask, what that is, you might not do it right, so then destroying the disk is probably a better route.

Note there doesn't seem to be any sure way of securely overwriting/erasing a new SSD disk. You'd have to destroy them to be sure. But I doubt anyone is throwing them out.
 
Perhaps discussing SSDs is irrelevant to old PC's and Laptops. Anyway....

Leo said:
The over-write tools will work on them in the same way.
Click to expand...

Apparently not

http://security.stackexchange.com/questions/12503/can-wiped-ssd-data-be-recovered

For instance, the FAST paper found that, in most cases, performing a full overwrite of all of the data on the SSD twice was enough to sanitize the disk drive, but there were a few exceptional cases where some of the data still remained present. There may be other reasons not to want to perform repeated overwrites of the full drive: it is very slow, and it may reduce the subsequent lifetime of the drive....

Moreover, the FAST paper found that standard utilities for sanitizing individual files were highly unreliable on SSDs: often a large fraction of the data remained present somewhere on the drive. Therefore, you should assume there is no reliable way to securely erase individual files on a SSD; you need to sanitize the whole drive, as an entire unit.

....

The most reliable way to securely erase an entire SSD is to use the ATA Secure Erase command. However, this is not foolproof. The FAST paper found that most SSDs implement this correctly, but not all. In particular, 8 of the 12 SSDs they studied supported ATA Secure Erase, and 4 did not. Of the 8 that did support it, 3 had a buggy implementation. 1 buggy implementation was really bad: it reported success, but actually left the data laying around.
Click to expand...
 
They're talking about tools that only overwrite files, not the entire drive. The tools on the link I provided offer the option of full-overwrites, including unallocated space.
 
performing a full overwrite of all of the data on the SSD twice was enough to sanitize the disk drive, but there were a few exceptional cases where some of the data still remained present.
Click to expand...

I read it differently. It would seem they tested all possibilities.

I would have thought fill a 60GB disk with 60GB of other data and that would be it. It works for HDD, but apparently not completely for SSD's. Its arguable that its probably good enough for most people.

Its also useful to consider how encryption helps with all this too.
 
There's no possible way it can't work for SSDs, they allocate file space using exactly the same file management system, be that NTFS or FAT. Once a bit is over-written, you cannot tell what was there previously. The tools that let you choose the overwrite pattern, carry out at least 2 over-writes, first using binary pattern 10101010, next using 01010101, so you're flipping all bits at least once. No way possible to recover data after that.
 
You're thinking at the software level. This problem is at much lower level. The hardware itself. The hardware doesn't work the same. You tell the HD to overwrite, its does. Tell a SSD to overwrite and it does something else (for some drives). The software might be telling it to overwrite, but the hardware (in a SSD) isn't doing that.

The other issue, is you (or the overwriting software) can't access all the space on the SSD.

Spare area, often on the order of 8% - 20% of the total flash is set aside for wear leveling purposes. The end user cannot write to this spare area with usual tools, it is reserved for the SSDs controller. But the spare area can hold (smaller) amounts of old user data.
Click to expand...

In summary overwriting works fine on a HDD. But not for a SSD.

For a SSD you need to use secure erase functionality by the drive manufacturer (which doesn't always work) or encryption.
 
I don't think most people will understand any of this, and might be better just physically destroying the drive.
 
That spare are won't have any of your files written to it, in only comes into play to replace damaged sectors, so again, not a problem.
 
But then factor in that unallocated NAND storage doesn't maintain previous state, so it's just blank unlike the traditional hard drives that maintain their magnetic charge. Maybe it is easier just take a hammer to it :D
 
Leo said:
There's no possible way it can't work for SSDs, they allocate file space using exactly the same file management system, be that NTFS or FAT. Once a bit is over-written, you cannot tell what was there previously. The tools that let you choose the overwrite pattern, carry out at least 2 over-writes, first using binary pattern 10101010, next using 01010101, so you're flipping all bits at least once. No way possible to recover data after that.
Click to expand...
Not correct. It's decades since operating systems were aware of the layout of hard drives in terms of physical tracks, sectors and blocks. Instead, they use logical block addressing (LBA) and let the device controller work out how an address maps onto the physical drive. Until recently, though, you could be guaranteed that a given logical address would map onto the same device location each time you used it. So if you looked at the blocks allocated to a given file in your FAT, you could guarantee to overwrite that file's contents by writing to the same logically numbered blocks. That's no longer true with SSDs. They have a separate map to translate from LBAs to solid state memory locations, and they intentionally alter the map to effect wear-levelling. Even though your FAT stays the same at the LBA level, the actual contents of the memory are constantly being shifted around.
 
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