The Asus VivoBook X1500EA 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 13NB0SR0L05011 and connector cable p/n 14010-00219800 for installation. If installing a Generation 4.0 x4 PCIe Drive, the drive will run at Generation 3.0 x4 max speeds.