The Asus Q504UX Laptop Supports Single and Dual Drive Configurations. (One 2.5" Solid State Drive or Hard Drive and/or One M.2 NGFF (2280) Solid State Drive) Note: If the 2.5" Drive was not installed from Asus, you will need the 2.5" Drive caddy p/n 13NB0BZ0AM0101 and cable p/n 14020-00120000 for installation. (The M.2 slot supports SATA and PCIe NVMe Solid State Drives)