A heat dissipation device includes a heat sink and two conductor bases. The heat sink includes two base plates attached to a graphics card and thermally connecting with two graphics processing units (GPUs) mounted on the graphics card, and a plurality of fins soldered on tops of the base plates. The conductor bases connect with the base plates of the heat sink and thermally connect with other electronic components mounted around the GPUs thereby to dissipate heat generated by the other electronic components. The GPUs and the other electronic components have different heights.