News WD Black SN850 SSD Sees Write Speed Drops in Chipset M.2 Slots

nostrocrompt

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Aug 27, 2015
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Ha, tfw a very random performance issue affects your rig. Well geez, what to do now? Can I swap my boot drive with my 850? I'm not wild about the idea... any idea if this is an issue that might get fixed at some point?
 

King_V

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In the case of AMD's X570 motherboards, it's public knowledge that there is a performance disparity between chipset-and processor-based M.2 slots. This is due to the higher latency on the latter.

Is this supposed to say "on the former," since it mentions the chipset first?
 
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Jun 4, 2021
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If The problem is about write speed then you should check out where the write test huge files are stored , it seems they share the chipset lanes om another SSD ? , that is are installed on a drive connected to the chipset as well ?

If the benchmark does not load the file into RAM before writing it to the SSD then the Benchmark software is the problem.
 

Sleepy_Hollowed

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Jan 1, 2017
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I wonder if this is with auto-PCIE detection. Sometimes the x570 on some motherboards, places the entire board in PCIE 3.0 when some devices are connected.

I've had to explicitly set it to 4.0 when those devices are present.
 

jpe1701

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This was an issue that popped up when x570 first came out with certain pcie 3.0 drives too. My hp ex950 has never been as fast as it was supposed to be. Some reviewers found it too but hp gave them firmware to fix the issue and then after the good reviews they never bothered to release the firmware for anyone else.
 
Jun 21, 2021
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If this is just write, I would be concerned its a SoC issue. Write is sensitive to PCIe latency, the SoC maybe doesnt have enough outstanding PCIe DMA's. If the latency is low enough it won't matter, but if SSD is connected to non CPU lanes there could be an issue.