A heat dissipation assembly for dissipating heat generated on a motherboard, includes a clip attached to the motherboard and above a first heat-generating component, and a heat sink rotatably mounted to the clip and thermally connected with the first heat-generating component. The heat sink includes an air outlet. The air outlet is adjustable to face a second heat-generating component of the motherboard via rotating the heat sink, for more effective use of airflow coming from the heat sink to cool the second heat-generating component.