Athena Power RM-4U455B85 Black SECC Japanese steel 1.2mm thickness 4U Rackmount Server Case W/EPS-12V V2.92 Active PFC 850W 6 (3 optional) External 5.25 Drive Bays Motherboard Compatibility: Up to 12 x 13 ATX or Xeon form factor Power Supply: W/EPS-12V V2.92 Active PFC 850W External 5.25 Drive Bays: 6 (3 optional) External 3.5 Drive Bays: 3 Expansion Slots: 7 External Slim Drive Bays: 1 x Slim CD-ROM Front Ports: Front USB dual socket 80mm Fans: 2