Corsair 900D HDD Drive Cage

The Obsidian 900D sports a total of nine 3.5” bays. Drives are inserted from left to right, and thus sit perpendicular to the case. The uppermost cage can be removed and mounted below the external 5.25” bays or installed at the bottom of the case, in front of the power supply. The caddies are made of plastic, and they allow tool-less drive installation. Locking or unlocking a loaded caddy into a cage is achieved with a lever that seems to work reliably (though empty trays are somewhat flimsy). Each caddy sports rubber grommets that decouple mechanical disks from the tray, while holding the drive in place with a metal pin. The grommets do their job; my microphone didn't pick up any major vibration or audible resonance from the identical 1 TB Samsung Spinpoint F3s I used for testingIn order to mount a hard disk in the tray, each of the caddy’s side rails needs to be bent slightly, allowing you to slide the locking pins into the drive's mounting holes.