Samsung Release Fix for Popular 840 EVO SSD Drive Performance Problems (again)

Samsung have released a new firmware update for their popular 840 EVO Solid State Drives. This fixes a problem that emerged on this series of drives which turned out to have an issue where performance (read and write speed) dropped off a cliff over time. This would turn a computer into one that initially was very quick, to one that becomes frustrating to use.

There was a fix for this problem released previously with a performance restore tool, but this appears to have been a temporary fix and the problem would later re-occur. So now in May 2015 Samsung have released a new firmware release for the 840 EVO SSD range, which promises to mitigate what is essentially a design fault in the drives for good.

We would thus strongly recommend that all clients with these popular drives in their computers apply the update via the Samsung Magician tool which is a free download from:

For clients under managed service agreements (Proactive IT support contracts), where we can see from the IT audit tools that Onega use that you have these drives installed, we'll be in contact shortly to schedule these updates when convenient for you. For clients on PAYG support, we'll also be in contact to ask if you'd like us to do this for you or to recommend you do this yourself (it is quite straightforward if you are competent).

Once the new firmware is on, there is a tool in the Magician Software that does a full refresh of the drive data. This is non-destructive but not to be interrupted while it runs, which can take some hours, so best started off of an evening. This will restore or maintain the data on the drive and make your computers run like new again. As the performance drop is gradual, you often don't notice the performance drop occurring, so a pleasant speed surprise when this is run.

By way of background, if you like to understand how things work, as we do; here are the technical details of what is occurring behind the scenes. The Samsung 840 drives use 19nm flash cells, which store the individual memory bits in vast quantities in these SSDs. They have a 'feature' whereby the charge in the cells decays over time so that they can take a number of read request cycles to read the data. When the amount of data to read is multiplied by the vast number of memory cells in the drive, then performance drops to about the speed (or worse) of a traditional magnetic hard drive. The data affected thus are files not regularly written. Most of your operating system, programs after install and data files will fall into this category as the amount of data on a drive that is changed every day is actually typically very small.  The fix essentially causes the drive to periodically move data on the drive behind the scenes to refresh this and keep the performance up thus. This will come at the expense of drive life to a limited extent, though realistically a computer will likely be replaced before end of drive life anyway as in a few years time we'll likely have 10TB SSDs where we currently have common capacities of 250Gb, 500Gb or 1TB.

Onega's policy on SSDs is to generally install Intel drives as first choice as these have excellent performance and reliability. Samsung next as they are just behind and coming in at slightly lower price points and thus, if we can, avoid any other brand of SSDs (or fit as an exception). Importantly Intel and Samsung both make their own silicon so have best control over quality in manufacturing. We've found that some drives can fail in case of power interruption and that others that purport to offer double the capacity of any other drive for the money are cheap for a reason and thus represent a false economy in a business environment where you need performance and reliability from a drive.

The current generation of drives like the Samsung 840 EVOs have a typical life expectancy of around five years under reasonably heavy load which exceeds the expected life of an office PC. The very latest Intel SSDs like the new Intel 750 series drives have an MTBF (Mean Time Before Failure) of 1.2 million hours, which works out to be 136 years which is pretty awesome and shows the unrelenting march of technology. By a back of envelope calculation you'd be running Windows 58 by then!