RIITOP Dual NVMe PCIe Adapter allows you add 2x M.2 NVMe SSD to Mainboard via a single PCI-e x8 Slot RIITOP Dual NVMe to PCIe Adapter Adopts ASMedia ASMedia ASM2812 Chipset, It does NOT depend on PCIe bifurcation supported by MOBO. Each SSD costs PCI-e 3.1 x4 Channel individually, non-interfering. (The final speed depends on the SSD and the Mobo's PCI-e bandwidth) Compatible with M.2 SSDs (PCI-e NVMe ): All Size 110x 22mm, 80x22mm, 60x22mm and 42x22mm. Hardware Requirement: Available PCI-e 8x/16x Slot on Mainboard, Compatible with PCI-e 3.0/2.0/1.0 standards Please NOTE: 1. This M.2 PCIe Adapter can Only Support M.2 PCI-e Based M Key Nvme SSD, DO NOT support PCI-e M Key AHCI SSD, SATA based B+M key or B Key SSD. 2. Please download driver of SSD from the brand official website if 'Disk Management' or 'Device Management' can not show the SSD. 3. Old MB can not support Booting from 'NVMe', Please confirm the MB's specification 4. Each SSD costs PCI-e 3.1 x4 Channel, NOT whole PCI-e 3.1 x8