The RocketRAID controller card itself is actually built on a half height PCI Express design that supports a total of four SATA ports which makes a perfect addition to a motherboard with four or more SATA ports already onboard, and with the PCI Express x1 interface you aren't limited to the PCI bandwidth that has held RAID from gaining performance crowns.
The back of the card contains the HighPoint 601 RAID management chip that not only allows for hot swapping out drives but also monitors the SMART functions of the drive.
The back of the card contains the four SATA ports that are stacked 2-by-2 to save as much space as possible. The Marvell 88SX7042 PCI Express chip actually supports up to PCI Express x4 speeds; however this will run at x2 or x1 speeds since the card only has a PCI Express x1 interface at the bottom of the card limiting it. However this is more than enough for basic RAID setups anyway.