2-6 General DescriptionInternal View3.5-inch Hard Disk Drive Model1 Drive baysThe last digit number indicates the drive bay number. Hard disk drive is optional.2 Backplane board3 Cooling fan (The last digit number indicates the fan number.)4 Power supply unit5 DIMM6 CPU/Heat sink7 Air duct8 PCI riser card9 Mother board10 Front panel board1-01-11-21-323-113-13-43-63-7 4105-15-2 6-16-27893-53-3