A variable area heat sink has a first heat sink area and a second heat sink area. A bridge is connected to the first heat sink area and includes a bi-metallic portion operable to connect and disconnect with the second heat sink area in response to a temperature change in the bridge which is sufficient to distort the bi-metallic portion from a first shape to a second shape. The first heat sink area may be installed in a computer chassis adjacent a first heat producing component. The second heat sink area may be installed in the chassis adjacent a second heat producing component. The combination of heat sink areas may be enlarged or reduced in size due to the coupling or uncoupling.