Legit Reviews just got confirmation from ASUS that they are removing the Marvell controller from the P7P55D EVO motherboard and nearly all other Intel P55 Express chipset boards due to yield issues over at Marvell. ASUS did say that they will offer SATA6G support on one board though, the P55 Premium. Legit Reviews contacted Marvell for comment this morning, but has not received a response. SATA 6G has been a work in progress ever since SATA-IO presented the draft specification of the 6 Gbit/s physical layer in July 2008, and ratified its physical layer specification on August 18, 2008.
Currently due to a Marvell yield issue this was planned as being present on the EVO but as of now has been removed from all of our P55 mass production boards. The only board that will ship with SATA6G support is our P55 Premium. Once Marvell get all issues resolves in terms of yield and a few other areas we will reintroduce this feature into our P55 boards. Hopefully that clarifies things.