If you own a Samsung 840 SSD, it appears that after much repeated and vocal pressure, Samsung has acknowledged the slow down also affects your drive. We're not talking about the EVO or the Pro, this is the original pure TLC model that launched (the EVO is a TLC+SLC cache hybrid while the Pro is all MLC). Here's the quote from Samsung, via Computer Base:
Uns ist durch das Feedback, das uns erreicht hat, bekannt, dass es auch beim Zugriff auf bestimmte Daten bei Modellen der SSD 840 zu niedrigeren Leseleistungen als angegeben kommen kann.
Im Moment untersuchen unsere Produktexperten systematisch die betreffenden SSD-Modelle innerhalb verschiedener Systemumgebungen und arbeiten an einer schnellstmöglichen Lösung.
Aufgrund der unterschiedlichen Technologien sind die Modelle der PRO-Serie (840 PRO und 850 PRO) nicht betroffen.
What? You can't read German? Neither can we, but paraphrasing from the poor quality translation from several online tools, we deduce that Samsung has acknowledged the issue on the 840, and is working on a solution as quickly as possible. This is similar verbiage to the statement issued for the 840 EVO acknowledgement.
** Update **
Thanks to Zyhmet, who commented shortly after posting, here's a human translation:
Because of the feedback we got, we realized that, accessing specific data with units of SSD 840 could lead to lower reading performance.
For the moment our experts are systematically examining the SSD-units with different system environments and we are working on a solution as fast as possible.
Due to different technologies the PRO-series (840 PRO and 850 PRO) are not affected.
** End update **
Side note – of those who have used the 840 EVO Performance Restoration Tool, a few have reported an issue cropping up. The error manifests as a SMART data misreporting error:
What's odd about this error is that it was present on some of our pre-production test samples (firmware EXT0AB0Q), and was corrected once we updated those samples to the first retail build (EXT0BB0Q). The image above was an actual screen shot taken during our temperature-dependency testing of the slow down issue. While none of our samples had the issue return when updating all the way to the performance restored firmware, one of those updates did corrupt the Master File Table, rendering the majority of the SSD inaccessible. While we have seen no other reports of corrupted partitions, several users noticed the SMART reporting issue after updating. It's odd to see this sort of a regression with firmware updates, in that a bug fixed in the initial shipping firmware has returned (for some) in a subsequent update. If you've updated your 840 EVO with their Performance Restoration Tool, it may be a good time to check your SMART attributes. If you see the error above, please leave us a note in the comments.
Circling back to the slow down issue – given that it is present in two TLC-based SSDs from Samsung, one has to wonder if this issue exists in other Samsung TLC SSDs as well. Here's the list of potentials (thanks to an anonymous comment on a prior story):
- 840 EVO – 19nm TLC
- 840 – 21nm TLC
- PM841 – 21nm TLC
- PM851 – 21nm TLC (some SKUs)
- 845DC EVO – 19nm TLC
- PM843 – 21nm TLC
- PM853T – 21nm TLC
We have several questions out to Samsung on these issues, but to date they have not been answered. More to follow as we wait for an official (English) response.