I just purchased this board hoping that I could connect 4 6GBp/s HD together in Raid 5. I am having similar issues. I am guessing that the Intel and Marvell controller don't work together in this manner. Let me know you ideas.
Both controllers operate independantly. You'll have to use the ICH10R, but for hard disks the Intel controller might be slightly faster. A hard disk just can't saturate a 3 Gbps SATA port.