In brief: The combination of Western Digital's Blackness SN850 SSD and an X570 chipset may sound appealing, but be careful how y'all ready it upward. A report has highlighted a problem in which the SSD's write speeds are heavily impacted when information technology's used in an Thou.two slot connected to the X570 chipset.

Update (06/22): WD contacted TechSpot with a statement and an update regarding an upcoming firmware fix for the functioning deposition, as previously reported. The firmware update will become available via Western Digital Dashboard software.

The statement reads: "The WD_BLACK SN850 NVMe SSD can experience a decrease in write functioning when connected to a chipset Chiliad.2 slot on certain motherboards, specifically when max payload size (MPS) is fix to 128 bytes (128B). To resolve this consequence, Western Digital will release a firmware update that eliminates a restriction in our product for this setting of MPS, expected to exist available by July 12, 2022."

The original story follows below:

The report comes from German site ComputerBase, which investigated complaints from forum users nigh the SN850 underperforming by testing the SSD.

The trouble stems from not all M.2 ports on a motherboard communicating directly with the processor due to the limited number of PCIe lanes on the CPU, leaving some slots connected to the chipset instead. Motherboard manufacturers take confirmed that going through the chipsets can result in college latencies due to the longer line paths, but the performance departure tends to be less than x%.

The Call of Duty-themed WD SN850 SSD

Testing the SN850 SSD on a Gigabyte Aorus X570 Master using the board's third M.ii slot, which is continued to the chipset, the publication discovered operation almost halved. CrystalDiskMark found the 1TB SSD managed a sequential write speed of just over three,200 MB/south, whereas placing the drive in the start, CPU-connected M.two slot pushed it to over 5,200 MB/s, near the manufacturer's claimed max speed of five,300 MB/s. The disparity was fifty-fifty greater in other tests, reaching 43.4%.

ComputerBase tested other PCIe 4.0 SSDs and found while at that place was a performance difference between the CPU-connected and chipset-connected slots, information technology was less than 10 percent, and at that place was no loss of write speeds with PCIe 3.0 SSDs.

Western Digital said it is investigating the issue and the causes. As noted by Tom'southward Hardware, it'due south suspected that the problem may be the X570 chipset detecting the SN850 SSD every bit Gen 3.0, as many PCIe three.0 SSDs have speeds of 3,200 MB/due south.