NVMe By

A slot that can do SATA will have the M key andor B key A slot that cannot do SATA will not have either the M or B key, but others instead

PCIe add-in cards, expansion units, and storage drives are sold separately Refer to the compatibility list for compatible devices Synology SNV3400 series

which slot is for fabric softener 2 expansion slot on the motherboard That is the adaptor allows a device to be connected to the PCIe bus, and that is what the slot

which slot do you put fabric softener in An NVMe solid-state drive, or SSD, is a high-speed storage device that implements the NVMe specification, which allows SSDs to use the PCIe bus