A server system comprises a deck, a front panel arranged on the deck and defining a collecting space; two doors arranged on opposite sides of the deck, and being perpendicular to the front panel; two receiving frame structures arranged between the doors in a back to back arrangement, and configured to receive multiple rows and columns of a plurality of storage drives horizontally, wherein two periphery corridors are each defined between one of the doors and one of the receiving frame structure facing the one door; two circuit boards arranged between the two receiving frame structures, wherein the two circuit boards comprise a plurality of slits, wherein a central corridor is defined between the two circuit boards; a storage cover disposed above the deck over the two periphery corridors, the central corridor, the two receiving frame structures, and the two circuit boards.