Pulling the side panel off the Carbide 300R we can get a good look at the inside of the case. The motherboard tray has a massive CPU cut out, molded in standoffs, and wire routing holes.
The 5.25″ drive bays are tool-less.
Bottom front is the tool-less hard drive cage. The cage holds 4 drive trays.
Each tray is can hold either a 2.5″ or 3.5″ drive.
The power supply area has a nice large vent. The supports for the power supply do not have any anti-vibration material on them.
In the top rear is the 120mm exhaust fan.
Pulling the front panel off we can see the pre-installed 140mm intake fan. There is space to install another 120/140mm fan.
The filter on the front panel is not removable. So to clean it you would have to pull the front panel off.
The front panel uses metal spring clips to hold it to the case frame. I like this over the plastic style. With the plastic clips it not a matter of if it will break, but when. The metal style should hold up to repeated removal of the panel for cleaning.
Behind the motherboard tray there is plenty of room to run cables, 20mm. What I would have liked to have seen more of is tie down points help pull wires tight to the back of the tray.