Methods and apparatus for disabling and enabling the receiver circuitry of a cable modem connected to a cable network headend are described. The cable network headend transmits a message to the cable modem to disable the receiver circuitry when a cable network headend determines that the cable modem is idle. The cable modem listens for messages on the cable network during activation windows between periodic intervals. Messages arriving during these activation windows can enable the receiver circuitry of the cable modem as well as synchronize the clocks of the cable network headend and the cable modem. The cable modem can also self enable its receiver circuitry and inform the cable network headend of its enabled state.