I saw the reviews of Asus X79, in this case Deluxe (my friend bought one) and here is a clip about SSD cashing: ASUS X79 - SSD Caching - YouTube Clearly you have to have 2 SSD - one is the OS drive, and the other SSD you use as a cash for the HDD. In other words you can not use your OS SSD to cash your HDD, becasue we can clearly see that before chasing the SSD is being formatted... 1) Why on earth the reviewer did not mention this KEY fact? 2) How much capacity do you really need? If Seagate Momentus XT drives have 4 Gb of SSD inside them, is not that enough already? Why do you need support for SSD cashing over 64 Gb? That just does not make sense.