A gas cooling device for cooling a heat source with a gas that is cooler than the heat source, the gas cooling device comprising: a parallel microchannel array cooler (100, 100') comprising: a base (110, 110') for transferring heat from the heat source; and one or more rows in a widthwise direction, each of the one or more rows comprising: fins (120, 120') in a lengthwise direction and separated by microchannels, the fins (120, 120') for dissipating the heat from the base; and a micro-plenum in the lengthwise direction between the fins (120, 120') and the base (110, 110') for distributing the gas in the lengthwise direction throughout the row and dispersing the gas to the fins (120, 120') via the microchannels, the gas for transferring the heat from the fins (120, 120'); and a manifold (200, 200') comprising: a plurality of nozzles (210, 210') associated with each of the one or more rows, the nozzles (210, 210') for delivering jets of the gas to the cooler, each of the nozzles (210, 210') for delivering one of the jets to a corresponding receiving point in the micro-plenum of one of the one or more rows. a parallel microchannel array cooler (100, 100') comprising: a base (110, 110') for transferring heat from the heat source; and one or more rows in a widthwise direction, each of the one or more rows comprising: fins (120, 120') in a lengthwise direction and separated by microchannels, the fins (120, 120') for dissipating the heat from the base; and a micro-plenum in the lengthwise direction between the fins (120, 120') and the base (110, 110') for distributing the gas in the lengthwise direction throughout the row and dispersing the gas to the fins (120, 120') via the microchannels, the gas for transferring the heat from the fins (120, 120'); and a base (110, 110') for transferring heat from the heat source; and one or more rows in a widthwise direction, each of the one or more rows comprising: fins (120, 120') in a lengthwise direction and separated by microchannels, the fins (120, 120') for dissipating the heat from the base; and a micro-plenum in the lengthwise direction between the fins (120, 120') and the base (110, 110') for distributing the gas in the lengthwise direction throughout the row and dispersing the gas to the fins (120, 120') via the microchannels, the gas for transferring the heat from the fins (120, 120'); and fins (120, 120') in a lengthwise direction and separated by microchannels, the fins (120, 120') for dissipating the heat from the base; and a micro-plenum in the lengthwise direction between the fins (120, 120') and the base (110, 110') for distributing the gas in the lengthwise direction throughout the row and dispersing the gas to the fins (120, 120') via the microchannels, the gas for transferring the heat from the fins (120, 120'); and a manifold (200, 200') comprising: a plurality of nozzles (210, 210') associated with each of the one or more rows, the nozzles (210, 210') for delivering jets of the gas to the cooler, each of the nozzles (210, 210') for delivering one of the jets to a corresponding receiving point in the micro-plenum of one of the one or more rows. a plurality of nozzles (210, 210') associated with each of the one or more rows, the nozzles (210, 210') for delivering jets of the gas to the cooler, each of the nozzles (210, 210') for delivering one of the jets to a corresponding receiving point in the micro-plenum of one of the one or more rows.