A:Answer You want to ADD a hard drive, or replace an existing?? You can add pretty much any modern-ish SSD, utilizing either the 2nd m.2 slot or, adding a SATA SSD/HDD in the rear/under mounting portion of the case. Just a warning though, cyberpower’s cable management is awful. A simple google or youtube search of anything similar will give you the perfect idea of how to add/replace SSD/HDD on modern builds.