2U chassis support max. motherboard size - 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, optional 2 x 2.5' hot-swap drive bay 12-Port 2U Backplane with Expander support up to 8 x 3.5' SAS3/SATA3 HDD/SDD and 4 x SAS3/SATA3/NVMe Storage Devices,HF,RoHS/REACH 1U 1200W/1000W Titanium Power Supply W/PMbus W76xL336xH40mm 7 low-profile expansion slot(s) 3 x 8cm high-performance PWM fan(s)