The SB800 has several improvements like
A-link Express 3.0, PCIe 5GHz x 4 PCI Express GPP - PCI-Express 2.0 @ 5GHz x 4 Support for AMD Fusion (up to C6) Integrated Ethernet Gb MAC Integrated Clock (Optional) SATA AHCI 1.2 SATA III Optional - Up to 6Gbps (optional) 14 USB 2.0