No SATA3 for my Samsung 840 500GB SSD on ASUS P8z77-V LK motherboard

Hi All,

I built this machine a while back, probably nearly a year ago. When I first set it up I remember managing to get my SSD to work on the SATA3 ports but then for some reason I ended up resetting the BIOS to it's defaults and now I can't get the BIOS to see the SSD at all when it is plugged into either of the SATA3 ports. The SSD works fine in the SATA2 ports (though clearly at a good deal less than it's optimum speed) so I haven't a clue what is up with it.

I am using a SATA3 rated SATA cable, I have SATA set in AHCI mode (though I have tried the other modes out of desperation with no success)

BIOS revision is up to date (version 1301)
SSD has been updated to firmware DXT09B0Q which I believe is the current version.

Just in case it is important the RAM is 2x4GB of Corsair 1600MHz in slots 2 and 4 (as specified by the mobo manual) and I am running Win 8 x64

Really would appreciate any help on this one. I have always managed to work these things out myself in the past but this has me completely stumped

With the drive connected to one of the SATA3 ports, try either loading optimized defaults or enable hot-plugging (SATA mode set to AHCI--> enable Hot Plug support). Save and exit, then re-enter the BIOS to see if the drive is recognized.