Key Features 2U chassis supports for maximum motherboard sizes - EE-ATX 13.68" x 13", E-ATX 12" x 13", ATX 12" x 10" motherboards 3 x 3.5" hot-swap SAS/SATA drive bay with SGPIO, optional 2 x 2.5" hot-swap SAS/SATA drive bay w/ full SES-II support on SAS motherboards 3-port SC825M SAS3 12Gbps TQ backplane, support up to 3x 3.5-inch SAS3/SATA3 HDD/SSD 1U 800W Redundant Power Supply 76mm width, W/PMbus, Titanium 7 low-profile expansion slot(s) 4 x 4cm high-performance counter-rotating PWM fan(s) with optimal fan(s) speed control Optional 1 x 4cm high-performance counter-rotating PWM fan(s) with optimal fan(s) speed control