Abstract: A computer system and method for measuring air density in a computer chassis. The computer chassis includes a fan, an ambient air temperature sensor, and a heat-generating device with a heat sink, a heat sink temperature sensor, and a controller. The controller controls the fan speed and applies a known amount of thermal energy to the heat sink, then determines the air density from the difference in temperature between the ambient air and the heat sink. The controller may then use the air density determination to adjust the air flow rate through the computer chassis to provide a proper air flow rate for cooling.

Abstract: A temperature isolation duct in a computer system comprising a chassis securing a circuit board and a fan system that draws air through the chassis, and a heat-generating component is mounted on the circuit board and exposed to the air flow. The hot air duct passively directs air heated by the heat-generating component from a single hot air duct inlet in direct downstream alignment with the heat-generating component to a single hot air duct outlet. A thermal sensor is secured within, or in direct alignment with, the hot air duct near the duct outlet for sensing the temperature of air flowing through the hot air duct and generating a temperature signal. A controller is in electronic communication with the thermal sensor for receiving the temperature signal and in electronic communication with the fan system for sending a fan speed control signal.

Abstract: A computer system and method for measuring air density in a computer chassis. The computer chassis includes a fan, an ambient air temperature sensor, and a heat-generating device with a heat sink, a heat sink temperature sensor, and a controller. The controller controls the fan speed and applies a known amount of thermal energy to the heat sink, then determines the air density from the difference in temperature between the ambient air and the heat sink. The controller may then use the air density determination to adjust the air flow rate through the computer chassis to provide a proper air flow rate for cooling.

Abstract: A temperature isolation duct in a computer system comprising a chassis securing a circuit board and a fan system, wherein the fan system draws air through the chassis in an airflow direction, and a heat-generating component is mounted on the circuit board and exposed to the air flow. The hot air duct passively directs air heated by the heat-generating component from a single hot air duct inlet in direct downstream alignment with the heat-generating component to a single hot air duct outlet, wherein the hot air duct has a length to width aspect ratio of greater than four. A first thermal sensor is secured within, or direct alignment with, the hot air duct near the duct outlet for sensing the temperature of air flowing through the hot air duct and generating a first temperature signal. A controller is in electronic communication with the first thermal sensor for receiving the temperature signal and in electronic communication with the fan system for sending a fan speed control signal.

Abstract: Systems and methods provide altitude-dependent fan control for a plurality of electronic subsystems using a shared air pressure sensor. Each server or multi-server chassis of a rack system is a subsystem of the rack system. Each subsystem receives its own on-board fan or blower module. The shared air pressure sensor senses air pressure and outputs a signal to all of the subsystems. Each subsystem then independently regulates its own fan speed according to the signal output by the shared air pressure sensor. Other fan operational parameters, such as the number of fans recruited, may also be controlled according to altitude according to the invention. A variety of other performance parameters, such as internal air or component temperature, ambient air temperature, server workload, and processor activity level, may also be factored into control of these fan operational parameters.

Abstract: A circuit board assembly includes a circuit board which defines circuit board pads, a set of surface mount electronic components soldered to a first set of the circuit board pads using a surface mount soldering process, and a set of surface mount coupling devices soldered to a second set of the circuit board pads using the surface mount soldering process. Each surface mount coupling device is configured to couple at least a portion of an object to the circuit board. Each surface mount coupling device includes a set of surface mount pads connected to the second set of the circuit board pads by solder joints resulting from the surface mount soldering process, a set of legs extending from the set of surface mount pads, and a body portion connected to the set of legs, the body portion providing a fixed structure relative to the circuit board for securing the object.