This Machine 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 HP, you will need the 2.5" Drive mounting bracket p/n 913937-001 and cable p/n 858969-001 for installation. (The M.2 slot support SATA and PCIe NVMe Solid State Drives)