2U, ATX 12" x 10", E-ATX 12" x 13", EE-ATX 13" x 13.68". Support up to ATX 12"x13" MB with rear 2.5" HDD option installed, 12 x 3.5" hot-swap SAS/SATA drive bay with SES3, 12-port 2U SAS3 12Gbps dual-expander backplane, support up to 12x 3.5-inch SAS3/SATA3 HDD/SSD (secondary expander port only connects to dual-port SAS devices, single-port SATA will not have this redundancy feature), 1U 920W Redundant Platinum Super Quiet power supply W/PMbus, 7 low-profile expansion slot(s), 3 x 8cm high-perfo