... USB with door Drive Bays: 5.25" x 4 External 3.5" x 1 External 3.5" x 6 Internal Mother Board: ATX Form Factor / P4 Ready Power Supply: ATX / P4 Slot Port: 7 Slots Optional: USB 2.0 / Audio / Video Fan 80 / 90 / 120 mm * 1 (Front) 80 / 90/ 120