The HP ProBook 6465b Notebook Supports Single and Dual Drive Configurations. (One 2.5" Solid State Drive or Hard Drive in the Primary Bay and One 2.5" Solid State Drive or Hard Drive in the Upgrade Bay) Note: If installing the second 2.5" Drive in the upgrade bay in replace of the optical drive, you will need the upgrade bay insert p/n 643921-001. If replacing the 2.5" Hard Drive for a 2.5" Solid State Drive, remove the bracket from the Hard Drive and install it on the Solid State Drive.