WD Black nvme super-slow

Win10 Pro
ASRock AB350M hard drive - latest drivers, latest BIOS

So, when I bought this bad boy, back in October 2018, it was scoring an avg transfer of 1121MB/sec per HDTune.

I thought things were a little odd, so I checked over the weekend - and now it’s at 256.3MB/sec.


This is slower than a SATA SSD.

Temp (per SSD dashboard) is at 57C.

Life remaining is 99%.

SMART says it’s… Oh. ■■■■. I was gonna say, “happy as a little clam,” because that’s what I recalled - but in the SSD it’s saying the SMART self-test isn’t supported.

So - what on earth happened?

How do I track this down?

It’s made the investment in this drive basically worthless…