A computing system comprising a housing; a chassis, arranged inside the housing; and a blade arranged in a slot of the chassis, wherein the blade comprises a first circuit board having a plurality of components (332, 334) mounted on a substrate; wherein the chassis is coupled to a cooling system to maintain at least a subset of the plurality of components (332, 334) operating in an environment having a temperature at or below 200 Kelvin; wherein the blade comprises a first heat spreader comprising a metal, wherein the first heat spreader is arranged to transfer heat from the first circuit board to the cooling system via an interface between a first surface of the first heat spreader and a second surface of the chassis, and wherein indium is permanently bonded to either the first surface of the first heat spreader, or the second surface of the chassis, or both the first surface of the first heat spreader and the second surface of the chassis; and wherein the housing is configured to maintain a lower pressure inside the housing than a pressure outside the housing; the blade further comprises a second circuit board, mounted on an opposite side of the first circuit board, having a second plurality of components (342, 344, 346, 348) mounted on a second substrate and a second heat spreader comprising a metal, wherein the second heat spreader is arranged to transfer heat from the second circuit board to the cooling system via a second interface between a third surface of the second heat spreader and a fourth surface of the chassis, and wherein indium is permanently bonded to either the third surface of the second heat spreader, or the fourth surface of the chassis, or both the third surface of the second heat spreader and the fourth surface of the chassis. a housing; a chassis, arranged inside the housing; and a blade arranged in a slot of the chassis, wherein the blade comprises a first circuit board having a plurality of components (332, 334) mounted on a substrate; wherein the chassis is coupled to a cooling system to maintain at least a subset of the plurality of components (332, 334) operating in an environment having a temperature at or below 200 Kelvin; wherein the blade comprises a first heat spreader comprising a metal, wherein the first heat spreader is arranged to transfer heat from the first circuit board to the cooling system via an interface between a first surface of the first heat spreader and a second surface of the chassis, and wherein indium is permanently bonded to either the first surface of the first heat spreader, or the second surface of the chassis, or both the first surface of the first heat spreader and the second surface of the chassis; and wherein the housing is configured to maintain a lower pressure inside the housing than a pressure outside the housing; the blade further comprises a second circuit board, mounted on an opposite side of the first circuit board, having a second plurality of components (342, 344, 346, 348) mounted on a second substrate and a second heat spreader comprising a metal, wherein the second heat spreader is arranged to transfer heat from the second circuit board to the cooling system via a second interface between a third surface of the second heat spreader and a fourth surface of the chassis, and wherein indium is permanently bonded to either the third surface of the second heat spreader, or the fourth surface of the chassis, or both the third surface of the second heat spreader and the fourth surface of the chassis.