A heat sink assembly for removing heat from two heat generating-components mounted on a printed circuit board, includes a first heat sink, a second heat sink, a plurality of poles each having a head at a top end and a double-layer spring. The first heat sink includes a base and a plurality of fins arranged on the base. The second heat sink has a first shoulder extending from a lateral side thereof. The first shoulder is disposed on the base. The double-layer spring includes an outer spring and an inner spring having a top end connected to a top end of the outer spring. One of the poles wearing the double-layer spring extends through the first shoulder and the base. The outer spring is compressed between the head of the pole and the first shoulder. The inner spring is compressed between the head of the pole and the base.