SATA Ports not working

Hi, I have an Asus P8H67-M LX motherboard with 6 SATA III ports in it.

Up until this weekend I have only been using two of them one HDD and one DVD drive. I purchased an SSD and did a fresh install of the Windows 7 OS onto it, with a view to using that for the OS and a few games, and the HDD for storage.

The problem I am having is that I cant get any of the remaining 4 Ports to recognize a drive attached to them.

While installing the SSD I changed the system to ACHI in the BIOS and enabled the remaining 4 ports. I know this worked because "Intel Rapid Storage Technology" can see the ports, but cant see the drive attached to them. I know the three drives work because I can use them in any combination of two on the working ports.

I have tried the exercise with two different SATA cables with no joy.

I cant imagine why it would make a difference but there may be a technical difference I don't know about, but the two SATA ports which work are grey and the 4 which I haven't been able to get working are blue.

I have downloaded all the latest drivers for the motherboard.

I am wildly out of my depth here, so please let me know what further information is required to help solve my issue.