Heat dissipating assembly

摘要

A heat dissipating assembly includes a heat sink ( 10 ) having a chassis ( 12 ), a back plate ( 30 ) and a plurality of fasteners ( 40 ). Each fastener includes a screw cap ( 42 ), a spring (44) and a sleeve ( 46 ). The screw cap and the sleeve are movably connected together. The screw cap includes a head ( 420 ) and a tube ( 422 ) extending from the head. The tube includes a first cavity ( 424 ) and a second cavity ( 426 ). The back plate forms a plurality of posts ( 34 ) passing through the chassis and threadedly engaging in the first cavities of the tubes. A spring ( 44 ) is compressed between the first cavity of the tube and a bottom wall of the sleeve, for providing appropriate downwardly pressing force on the chassis of the heat sink against a CPU ( 22 ) mounted on a PCB ( 20 ).