My Kingstone 256 GB SSD has done 1.85 TBW and still Crystal Disk Info shows Health: 100%. Why is that? As far as I know it is rated at 150 TBW, so it should take 1% of health on every 1,5 TBW. In my case it should be now showing Health: 99%, not 100% still.
Robert J
Favorite Answer
Many SSDs use "Over provisioning", with a few percent excess capacity that can be automatically mapped in to replace failed sectors/clusters.
Plus, some SSD controllers use transparent data compression when writing and decompress the data as its read back.
That can mean if the written data was highly compressible, the data volume written to the flash memory may be far less than externally transferred to the drive.
And, the write rating will be a predicted estimate; it may in reality be quite a bit off and it have a significantly higher write rating than the estimate.