WD_Black SN850 SSD Firmware Update Fixes Write Performance On AMD X570 Boards

WD Black SN850 SSD
Imagine paying a premium for a blazing fast PCI Express 4.0 solid state drive only to discover that it coughs up a hairball on your specific PC platform. Sour grapes, right? Well, that is the situation some owners of X570 motherboards found themselves in when slapping a WD Black SN850 SSD into their PC, but fortunately there is now a fix available.

Let's back up a moment. The issue garnered attention last month when users noticed a precipitous drop in write performance—over 43 percent, according to some online benchmark data. To be fair, this decline in write performance did not make the SSD slow (it was still hitting speeds of around 3,000MB/s), just slower than it should have been (it's rated to write data at 5,300MB/s).

WD acknowledged the issue, saying in a statement that some owners may "experience a decrease in write performance when connected to a chipset M.2 slot on certain motherboards, specifically when the max payload sizes (MPS) is set to 128 bytes (128B)."

The bug only appeared to affect motherboards based on AMD's X570 chipset, and only when plugged into an M.2 slot that is connected to the chipset, rather than the CPU.

"To resolve this issue, Western Digital will release a firmware update that eliminates a restriction in our product for this setting of MPS, expected to be available by July 12, 2021," WD added.

True to its word, WD this week rolled out a firmware update for its Black SN850 SSDs, version 613200WD, and a user on the ComputerBase forums ran some benchmarks that appear to indicate the write issue has indeed been resolved. Have a look...

WD SN850 Benchmarks
Click to Enlarge - Benchmarks with new firmware on the right (Source: MichaelMros)

The benchmark scores on the left were obtained with firmware revision 613000WD, while the numbers on the right represent scores obtained with the new 631200WD firmware release, which is supposed to squash the write bug. And it appears the firmware does exactly that (the column on the right contains the write scores).

Looking at the sequential write performance, the WD Black SN850 went from 2,821.63MB/s with the old firmware to 5,115.11MB/s after installing the new firmware. That is a massive 81.3 percent jump in performance. The rest of the figures look good already, though the numbers still show some less dramatic gains with the new firmware in place.

If you own a Black SN850 SSD, you can obtain the new firmware through the Western Digital Dashboard utility. As always when performing a firmware update, it is a good idea to back up any important data beforehand, on the off chance that something goes awry. As they say, an ounce of prevention is worth a pound of cure.

It's good to see WD address this bug so quickly. The Black SN850 is one of the faster drive families, with sequential reads rated to hit 7,000MB/s on all three capacities (2TB, 1TB, and 500GB), and sequential writes rated to hit 5,100MB/s on the 2TB model, 5,300MB/s on the 1TB model, and 4,100MB/s on the 500GB model.