A cooler for heat generating electronic components comprising a heat exchange plate configured for heat exchange communication with one or more heat generating electronic components includes a fin stack having a plurality of heat exchange fins and one or more heat pipes and/or thermosyphon tubes in heat exchange communication with the heat exchange plate and said plurality of fins, and a fan for directing air to and/or from the fins, each of said fins having a centered interior circular opening or hole, the fins stacked with the holes coaxially aligned and substantially centered in the fin stack and defining an elongated cavity having a first open end adjacent to the heat exchange plate and a second open end adjacent to the fan, and an elongated insert centrally positioned lengthwise along the cylindrical cavity and having a exterior surface of revolution smaller than the diameter of the cavity and defining an airflow channel between the insert and the fin openings and wherein the exterior surface of revolution of the insert is shaped, tapered or slanted and/or the interior openings of the fins are of the same or different diameters to provide an airflow channel width increasing from the fist end to the second end.