The Disk Drive Bays
The Corsair Obsidian 650D has four 5.25” external bays, one external 3.5”/2.5” bay with hot-swap connectors, and six 3.5”/2.5” internal bays, all using tool-less installation mechanisms. However, you must use regular screws to install 2.5” devices.
The six internal 3.5” bays are divided into two hard drive cages. The top one is removable (it is fastened to the case using two black thumbscrews), allowing you to install longer video cards. This cage can be completely removed from the case or moved to the bottom panel of the case. In this case, you are limited to power supplies up to 7.9” (200 mm) in length.
Each hard drive bay is actually a drawer. While 3.5” devices can be installed without the use of screws, you need to use screws when installing 2.5” devices. The pegs that hold 3.5” devices have a silicone ring around them in order to reduce the vibration, and thus noise, produced by the hard drive.