An assembly for cooling two or more heat generating components, comprising: a support having an inlet for receiving cooling fluid and an outlet for expelling the cooling fluid, the support including first and second cavities (11a, 11b) formed in an upper surface, each cavity in fluid communication with the inlet and the outlet; first and second heat generating components each having a bottom heat transfer surface, the first and second heat generating components arranged to be positioned over the first and second cavities, respectively, and respectively having first and second heat removal requirements; and first and second manifold elements each having a plurality of interdigitated inlet and outlet channels (25, 26) that are open at an upper surface of the manifold element, the first manifold element arranged to be received in the first cavity with portions of the upper surface in contact with the heat transfer surface of the first heat generating device such that cooling fluid can flow from the inlet channels upwardly into a space between the upper surface of the manifold element and the heat transfer surface so as to contact the heat transfer surface and downwardly into an outlet channel, the second manifold element arranged to be received in the second cavity with portions of the upper surface in contact with the heat transfer surface of the second heat generating device such that cooling fluid can flow from the inlet channels upwardly into a space between the upper surface of the manifold element and the heat transfer surface so as to contact the heat transfer surface and downwardly into an outlet channel; wherein the inlet and outlet channels and the upper surface of the first and second manifold elements are arranged to provide first and second restrictions to flow, respectively, through the manifold element that are matched to the individual heat removal requirements of the respective heat generating components. a support having an inlet for receiving cooling fluid and an outlet for expelling the cooling fluid, the support including first and second cavities (11a, 11b) formed in an upper surface, each cavity in fluid communication with the inlet and the outlet; first and second heat generating components each having a bottom heat transfer surface, the first and second heat generating components arranged to be positioned over the first and second cavities, respectively, and respectively having first and second heat removal requirements; and first and second manifold elements each having a plurality of interdigitated inlet and outlet channels (25, 26) that are open at an upper surface of the manifold element, the first manifold element arranged to be received in the first cavity with portions of the upper surface in contact with the heat transfer surface of the first heat generating device such that cooling fluid can flow from the inlet channels upwardly into a space between the upper surface of the manifold element and the heat transfer surface so as to contact the heat transfer surface and downwardly into an outlet channel, the second manifold element arranged to be received in the second cavity with portions of the upper surface in contact with the heat transfer surface of the second heat generating device such that cooling fluid can flow from the inlet channels upwardly into a space between the upper surface of the manifold element and the heat transfer surface so as to contact the heat transfer surface and downwardly into an outlet channel; wherein the inlet and outlet channels and the upper surface of the first and second manifold elements are arranged to provide first and second restrictions to flow, respectively, through the manifold element that are matched to the individual heat removal requirements of the respective heat generating components.