Serial fan cooling subsystem for computer systems

A method of providing cooling for a chassis of a computer system, said computer system having at least one specified device to be cooled, said cooling subsystem comprising the steps of:

• driving first and second cooling fans with associated first and second motors, respectively;
• and
• providing a pathway for air communication between said first and second cooling fans with a common plenum substantially shrouding said first and second fans, said first and second cooling fans cooperating to provide an optimum rate of air flow from without said chassis to within said chassis to provide air exchange within said chassis, said air flow within said chassis being in a predetermined direction to provide directed cooling of said specified device within said chassis, said common plenum free of said specified device, said common plenum allowing said first and second fans to continue to cooperate to provide a minimum air flow to provide a minimum air exchange within said chassis, said air flow remaining in said predetermined direction to continue said directed cooling of said specified device when a selected one of said first and second motors fails.