PCIE X4 transfer protocol M.2 NGFF solid-state hard drive is divided AHCI protocol and NVME protocol two Windows 7 can not recognize the NVME protocol solid-state hard drive which requires special attention!
U.2 NVMe drive connects directly to the SFF-8639 connector on the adapter and the adapter connects directly to the computer motherboard. The adapter is compatible with PCIe 3.0 motherboards and is also backward compatible with PCIe 2.0 and PCIe 1.0.
The 2.5" SATA Drive is directly powered by the PCIe slot but the data is not pass-through the PCIe slot. A SATA cable is require to connected to the SATA port and connect it directly to any free SATA port on the motherboard.
When install OS with NVMe SSD please make sure Motherboard BIOS can be support PCIE SSD to boot up. For Windows Server 2012 R2 or the latest OS have included NVMe SSD driver. When use the old OS that you must install the driver that provide from the SSD vendor.