HDD Sata 2 works like sata 1

Connected to sata 3, changed cables, did not help.
Ports work, other drives work as they should. What could be the problem?

No expert here but I think M.2 slots share SATA slots. So if you have an M.2 card installed it might be sharing the same SATA connection you have used for this drive.

Just a thought…

Yes, something similar was in the description for my motherboard, but m2 was not installed and ~6 months ago everything was in order.