This Machine Supports Single and Dual Drive Configurations. (Two 2.5" Solid State Drives or Hard Drives) Note: If replacing the 2.5" Hard Drive for a 2.5" Solid State Drive, remove the hard drive bracket and connector from the hard drive and install it on the solid state drive. If installing the second 2.5" Drive, you will need the 2.5" Drive hardware kit p/n 434106-001 (Includes: Second 2.5" Drive bracket and screws) for installation.