I think the EVO 850 are all SATA, not PCIe. But in general, yes, they should at least appear on the bus...
Interestingly, when this happenned to me, with some "ADATA" SSDs they would still negotiate a link speed, so their PHYs did get initialized. But Linux didn't get any further information from the disks, device type, name capacity... So maybe their firmware crashed halfway through initializing the SSD.
Interestingly, when this happenned to me, with some "ADATA" SSDs they would still negotiate a link speed, so their PHYs did get initialized. But Linux didn't get any further information from the disks, device type, name capacity... So maybe their firmware crashed halfway through initializing the SSD.