Software Update: CrystalDiskInfo 9.3.0 – Computer – Downloads

Those things don’t last forever, but by the time you have to replace it you will probably be long overdue for another system. Mind you, a mechanical drive won’t let you know until just before it breaks, if at all and you’re in for a surprise. And mechanically has the property of containing more mechanical complexity, is susceptible to vibrations and therefore has more point of failures and therefore has no chance of living as long as the SSD.

Now it is true that an SSD can also die suddenly, that percentage does not say much except that this is the official stated lifespan of the SSD from the manufacturer, but endurance tests have already shown that SSDs last much longer than this. specification, up to several times, but that of course falls outside the ‘official guaranteed lifespan’.

Couple of these SSD endurance tests:

Web archive mirror with images of the techreport review:But that official lifespan also says quite little, as Elcomsoft has investigated:
Elcomsoft.com – Why SSDs Die a Sudden Death (and How to Deal with It)

Why SSD Drives Fail with no SMART Errors

SSD drives are designed to sustain multiple overwrites of its entire capacity. Manufacturers warrant their drives for hundreds or even thousands of complete overwrites. The Total Bytes Written (TBE) parameter grows with each generation, yet we’ve seen multiple SSD drives fail significantly sooner than expected. We’ve seen SSD drives fail with as much as 99% of their rated lifespan remaining, with clean SMART attributes. This would be difficult to attribute to manufacturing defects or bad NAND flash as those typically account for around 2% of devices. Manufacturing defects aside, why can an SSD fail prematurely with clean SMART attributes?

Each SSD drive has a dedicated system area. The system area contains SSD firmware (the microcode to boot the controller) and system structures. The size of the system area is in the range of 4 to 12 GB. In this area, the SSD controller stores system structures called “modules”. Modules contain essential data such as translation tables, parts of microcode that deal with the media encryption key, SMART attributes and so on.

If you have read our previous article, you are aware of the fact that SSD drives actively remap addresses of logical blocks, pointing the same logical address to various physical NAND cells in order to level wear and boost write speeds. Unfortunately, in most (all?) SSD drives the physical location of the system area must remain constant. It cannot be remapped; wear leveling is not applicable to at least some modules in the system area. This in turn means that a constant flow of individual write operations, each modifying the content of the translation table, will write into the same physical NAND cells over and over again. This is exactly why we are not fully convinced by endurance tests such as those performed by 3DNews. Such tests rely on a stream of data being written onto the SSD drive in a constant flow, which loads the SSD drive in unrealistic manner. On the other side of the spectrum are users whose SSD drives are exposed to frequent small write operations (sometimes several hundred operations per second). In this mode, there is very little data actually written onto the SSD drive (and thus very modest TBW values). However, system areas are stressed severely being constantly overwritten.

Such usage scenarios will cause premature wear on the system area without any meaningful indication in any SMART parameters. As a result, a perfectly healthy SSD with 98-99% of remaining lifespan can suddenly disappear from the system. At this point, the SSD controller cannot perform successful ECC corrections of essential information stored in the system area. The SSD disappears from the computer’s BIOS or appears as empty/uninitialized/unformatted media.

If the SSD drive does not appear in the computer’s BIOS, it may mean its controller is in a bootloop. Internally, the following cyclic process occurs. The controller attempts to load microcode from NAND chips into the controller’s RAM; an error occurs; the controller returns; an error occurs; etc.

However, the most frequent point of failure are errors in the translation module that maps physical blocks to logical addresses. If this error occurs, the SSD will be recognized as a device in the computer’s BIOS. However, the user will be unable to access information; the SSD will appear as uninitialized (raw) media, or will advertise a significantly smaller storage capacity (eg 2MB instead of the real capacity of 960GB). At this point, it is impossible to recover data using any methods available at home (eg the many undelete/data recovery tools).

Which means that if the system area of ​​the SSD is so worn, which you cannot deduce from the percentage that these tools can read, the SSD can still break. Usually they become read-only when you have written so much so that you can still extract the data, but the situations I have seen so far is that they first generate a lot of errors in the sectors, freeze, slow down, until they no longer work at all. are recognizable in the bios and that’s the end of the exercise.

This also happened with a few Samsung 850 Pros in a friend’s X99 system, despite the fact that they had few or even very few writes, but had been running for many hours. The end of the exercise was also quite close together.

Here is an overview of a few SSDs that I use:

What I think is a shame is that CrystalDiskInfo cannot view historical statistics for different storage media, like HD Tune Drive Status can: