I notice a few people having problems with their drives showing as 3Gb/s when they should get 6, I had a similar problem when I was setting mine up.
I had it plugged into an intel port on a MSI P67A-GD53, so I expected to be running at 6Gb/s, but when I got everything sorted my benchmarks were low and the Intel RST tool was telling me I was only running at 3Gb/s
Turns out the problem was my SATA cable. I originally used an older SATA cable to connect it to the board and only got 3Gb/s, but when I tried a new cable it worked fine and was detected as 6Gb/s straight away. I know you're not supposed to need new cables for 6Gb/s but perhaps mine were poorly shielded or something![]()
This won't help if you're controller is crappy, but it's one more thing to try!
TL;DR: Try another SATA cable if you're having trouble with your drive showing as 3Gb/s when you're sure you should get 6Gb/s
I've got the exact same board and I use the SATA cables which came with the motherboard and they actually run fine for me on my Crucial M4. What cables were you using originally?
Liam