Info Samsung "Slow Bug" PM851 M.2 SATA SSD, five years later...

Replay

Golden Member
Aug 5, 2001
1,362
65
91
Wanted to share some new test screens from an old-stock pull Samsung OEM M.2 TLC SATA SSD with the "Slow Bug". It is about to go into a project.
The five year old data has become unbelievably slow. Looking on the bright side, the blank parts of the drive are still fairly fast. :D
BTW, I have been using half a dozen of these drives for years. When they start to slow down, maybe once or twice a year, I will run a utility called DiskFresh which rewrites all of the data and restores full speed operation.


HDTune_Benchmark_SAMSUNG_MZNTE256HMHP-000_2nd-scan-today.pngHDTune_Info_SAMSUNG_MZNTE256HMHP-000.pngHDTune_Health_SAMSUNG_MZNTE256HMHP-000.pngHDTune_Benchmark_PM851-x2-July-11-2019-after-DiskFresh-read-only_Intel___Raid_0_Volume.png

Samsung M.2 TLC PM851. 256G M.2 SSD SATA drive, 26 power on hours, 39 GB used 188 GB free (237GB capacity). Drive date code 1441.
Windows folder created 7/10/2015. No data written since 3/3/2016, and almost all files are from 2015.
Came out of a Lenovo Yoga 3 Pro upgraded to Windows 10 (file version 10.0.10240.16384). I also have HP and Dell versions of this drive.

HD Tune 2.55 read-only Benchmark settings: 64K blocks and one step below most Accurate.

Samsung 840 EVO was patched. OEM versions of this drive were not well supported.


 

coercitiv

Diamond Member
Jan 24, 2014
6,151
11,686
136
Here's the younger PM951 brother after a few years in a low I/O system with 24/7 uptime:
Screenshot 2021-02-18 121522.png

Here's the disk after the first 50% of stored data was refreshed using DiskFresh:
Screenshot 2021-02-18 131651.png

and now let's go to 100%:
Screenshot 2021-02-18 135611.png
 

D0M1N13

Junior Member
Feb 2, 2013
14
0
66
Wanted to share some new test screens from an old-stock pull Samsung OEM M.2 TLC SATA SSD with the "Slow Bug". It is about to go into a project.
The five year old data has become unbelievably slow. Looking on the bright side, the blank parts of the drive are still fairly fast. :D
BTW, I have been using half a dozen of these drives for years. When they start to slow down, maybe once or twice a year, I will run a utility called DiskFresh which rewrites all of the data and restores full speed operation.


View attachment 39863View attachment 39864View attachment 39865View attachment 39866

Samsung M.2 TLC PM851. 256G M.2 SSD SATA drive, 26 power on hours, 39 GB used 188 GB free (237GB capacity). Drive date code 1441.
Windows folder created 7/10/2015. No data written since 3/3/2016, and almost all files are from 2015.
Came out of a Lenovo Yoga 3 Pro upgraded to Windows 10 (file version 10.0.10240.16384). I also have HP and Dell versions of this drive.

HD Tune 2.55 read-only Benchmark settings: 64K blocks and one step below most Accurate.

Samsung 840 EVO was patched. OEM versions of this drive were not well supported.



Thanks for the info. I have a PM981A version of this drive and to tell you the truth, it is not blazing fast. I have the PM981A in my Asus Zephyrus S17 GX701 laptop. The speeds are not that all impressive and I am getting half of what Samsung claimed the speeds should be. This is just unacceptable. Probably the PM981A will also suffer this "slow bug" after a couple of years. I was thinking of replacing it with a Samsung 970 Pro but I probably won't feel the difference anyways.