Abstract: A loop thermosyphon can combine the best of heat-pipes and traditional liquid-cooling systems that include a mechanical pump. A disclosed heat-transfer device includes a first heat-transfer component and a second heat-transfer component fluidly coupled with each other by a first conduit and a second conduit. A first manifold is positioned in the first heat-transfer component and defines a first plurality of liquid pathways. The first manifold fluidly couples with the first conduit. A second manifold is also positioned in the first heat-transfer component and defines a second plurality of liquid pathways fluidly coupled with and extending from the first plurality of liquid pathways. The second manifold further defines a plurality of boiling channels, a plurality of accumulator channels and a vapor manifold. The boiling channels extend transversely relative to and are fluidly coupled with the second plurality of liquid pathways.