Aspects of a method and system for optimized power management for a network device supporting PCI-E and energy efficient Ethernet are provided. In this regard, in a network interface controller that supports energy efficient Ethernet, a PCI-E core may be transitioned from a low power PCI-E state to a full power PCI-E state when a PHY core in the network interface controller initiates transition from a low power mode to a full power mode and before the PHY core receives an Ethernet packet. In another embodiment, the PHY core in the network interface controller may be transitioned from a low power mode to a full power mode when the PCI-E core initiates transition from a low power PCI-E state to a full power PCI-E state, and before the PCI-E core receives a command to send an Ethernet packet.