Various embodiments disclose a shielded or isolated heat dissipating system comprising a case, a heat sink base, and a circuit board comprising at least one electronic device for which heat dissipation is desired. The heat sink base is attached to the case and together with the shielding case defines an enclosed space within which electromagnetic interference is reduced. Both heat-dissipation function and electromagnetic shielding function may be achieved by the combination of the heatsink base and the case while maintain electrical isolation with one or more specially treated components. The space required for mounting the system may also be reduced without adversely affecting normal and stable operation of the electronic device.