Premium Intel Pedestal Chassis (standard) or 6U Rackmount (w/ addition of rack conversion kit) Hotswap Hard Drives(w/ addition of hot-swap drive module and mounting kit) Additional RAM must be installed in matched pairs Contact your sales rep to add hardware not offered in this configurator If installing DVD drive there is only enough space for 5 hard drives If installing additional cpu you must install additional RAM (1 matched pair per cpu) FYI - Memory will operate at 1066MHz only for E5520, E5530, E5540 cpus. Speed drops to 800MHz for all others.