there is a Marvell "Kirkwood" 88F6281 clocked at 1.2 GHz. RAM has been bumped up to 256 MB and a Marvell 88E1118 is used for the Gigabit Ethernet port.
Write performance averaged over the 32 MB to 4 GB file sizes comes in at 39.8 and 36.8MB/s for 1000 Mbps and 1000 Mbps + 4K jumbo connections respectively. Read speeds averaged 50 and 42.1 MB/s for 1000 Mbps and 1000 Mbps + 4K jumbo connections. While this might not sound impressive, it puts the XHL at the top of the NAS Charts when you look at just single drive NASes.