In Gigabit Ethernet Systems, the Trusted Platform Module (TPM) is designed to provide trust and security to a platform through integrity measurement, protected storage, and other cryptographic functions. The present invention relates to a TPM-LAN chip with separate TPM and LAN power management. The TPM-LAN chip is designed such a way that power is reduced significantly in different power management modes compared to the legacy devices. This is accomplished by turning off certain clocks during certain operating modes.