4 x 3.5" hot-swap SAS/SATA 4-port 1U TQ backplane (W/ enclosure management) 1U 600/680W Multi-output 80PLUS gold power supply, 24pin output 1 full-height & half-length expansion slot(s) (Riser Card Required) 4 x 4cm high performance PWM fan(s) Optional 1 x fan for PCI card cooling