Four Intel® Xeon MP Processors at 1.50GHz/1MB Processor, up to 8 supported (populated in groups of 4) with 400MHz FSB and the HP developed F8 Chipset, 2048MB addressable protected 133MHz ECC SDRAM Memory standard, 64GB maximum with optional Hot Plug RAID Memory (front access), Two 1150/500 Watt Hot Plug Redundant Power Supplies Standard, Four 1" Hot Plug SCSI Hard Drive bays available, Eleven total Hot Plug slots (10 - 64bit/100MHz PCI-X, 1 - 64bit/33MHz), 7U rack-optimized modular chassis, Most complete investment protection solution in the industry through a modular-upgrade strategy, One (1)