In one embodiment a blower comprises a case comprising a first surface, a second surface opposite the first surface, and a side wall extending between portions of the first surface and the second surface, wherein the side wall comprises an air inlet and an air outlet, an impeller disposed in the case and rotatable about an axis of rotation extending through a hub, wherein the impeller comprises a plurality of blades which define a gap with the hub, wherein portions of the side wall are disposed at least a first distance from the axis of rotation and the impeller is to define a circumferential airflow path within the case, wherein the impeller is to create an airflow in the circumferential airflow path between the air inlet and the air outlet, and a feature disposed in the gap to impede recirculation of air in the case.