The Lenovo ThinkPad X1 Extreme 4th Gen Laptop Supports Single or Dual Drive Configurations Depending on the Graphics Card Installed. (One M.2 (2280) SSD Slot with the NVIDIA GeForce RTX 3060/3070/3080 Graphics Card) or (Two M.2 (2280) SSD Slots with the Intel UHD Graphics or NVIDIA GeForce RTX 3050 Ti Graphics Card) Note: M.2 slot 1 (slot A NVMe0) supports Generation 4.0 x4 and 3.0 x4 speeds and M.2 slot 2 (slot B NVMe1) supports Generation 3.0 x4 speeds. The SSD with PCI Gen 4.0 x4 Performance is downgraded to closer to PCIe Gen 3.0 x4 Performance in M.2 Slot 2 (Slot B NVMe1). This machine supports RAID 0/1 configurations.