Unable to use 2nd NVME SSD

2 M key slot is compatible with both B+M key SSD and M key SSD The last but not least, you should check whether the slot supports PCIe (

2 slots are used for SSDs, for example the E Key slot in the following picture is reserved for wireless module You will find the location

m2 vs nvme 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

m2 pcie 40 in 30 slot SATA is just a complete wasted slot ; all slots should be dual NVMESATA capable, or