A heat dissipating assembly for dissipating heat from a graphic card and a hard disk driver (30), includes a heat sink (10) for contacting the graphic card and a fan duct (20) fixed on the heat sink. The fan duct is made by bending a planar metal plate and has a first portion soldered to a top face of the heat sink and a second portion slantwise and upwardly extending from the first portion. When a fan (40) generates an airflow towards the heat sink, a part of the airflow flows through the heat sink to remove heat in the heat sink, and another part of the airflow is guided slantwise and upwardly by the second portion of the fan duct to flow through the hard disk driver, thereby to cool the hard driver.