NVME M2 drives: which slot to use?

NVME M2 drives: which slot to use? m 2 nvme slot on motherboard ASUSTOR LOCKERSTOR 2 2 BAY WITH 2 SLOTS-image · ASUSTOR DRIVESTOR 4 NAS-image · SAMSUNG 990 PRO SSD 2TB PCIe · TEAM TFORCE A440 m2_1 slot ASUSTOR LOCKERSTOR 2 2 BAY WITH 2 SLOTS-image · ASUSTOR DRIVESTOR 4 NAS-image · SAMSUNG 990 PRO SSD 2TB PCIe · TEAM TFORCE A440

m2_1 slot Ready for higher capacity and even faster Type 2280 NVMe SSD to fulfill the need of performance Besides the onboard LAN port, users may also choose

m24 slot 2 standard contains variants with up to four PCIe lanes, one SATA 6 Gbs and or one USB port So it is possible to connect PCIe as well as SATA SSDs  2 slots are not compatible with both SATA and NVMe in my experience Only end consumer motherboards have that