82551ER

Enhanced IP Protocol Support
    -TCP, UDP, IPv4 Checksum Offload
    -Received Checksum Verification
Quality of Service (QoS)
    -Multiple Priority Transmit Queues
Optimum Integration for Lowest Cost Solution
    -Integrated IEEE 802.3 10BASE-T and 100BASE-TX compatible PHY
    -32-bit PCI master interface
    -Thin BGA 15mm² package
Integrated power management functions
    -ACPI and PCI Power Management standards compliance
    -Wake on "interesting" packets and link status change support
High Performance Networking Functions
    -Early release
    -8255x controller family chained memory structure
    -Improved dynamic transmit chaining with multiple priorities transmit queues
    -Full pin compatibility with the 82559 and 82559ER controllers
    -Backward compatible software to 82559ER controller
    -Full Duplex support at 10 and 100 Mbps
    -IEEE 802.3u Auto-Negotiation support
    -3 Kbyte transmit and receive FIFOs
    -Fast back-to-back transmission support with minimum interframe spacing
    -IEEE 802.3x 100BASE-TX Flow Control support
    -Adaptive Technology
Low Power Features
    -Advanced Power Management capabilities
    -Low power 3.3 V device
    -Efficient dynamic standby mode
    -Deep power down support
    -Clockrun protocol support
82551ER Enhancements
    -Improved Bit Error Rate performance
    -HWI support
    -Deep Power-down state power reduction