If you have one of the following WD SATA3 HD's read on:
WD1002FAEX-00Y9A0
WD7502AAEX-00Y9A0
WD6402AAEX-00Y9A0
WD5002AAEX-00Y9A0
WD5002AAEX-32Y9A0
Apparantly WD had a few batches of SATA3 HD's that did not correctly report themselves to BIOS as 6 Gb/s capable listed above. I found this out when I looked at the devices attached to my Marvell SATA3 controller, and they showed up as running at only 3 Gb/s. A web search led me to the solution which was contact WD technical support for a patch to correct the HD. It's nice to learn at least one problem was not due to the mobo BIOS