I have done exactly what you said, I have installed windows 10 on SSD as C drive, no problem but after I shut down my computer and connected the main Hard drive wires for power and data cable to the computer, it does not read the main Hard drive so I cannot see D drive. Any suggestions on this please. This is what I have on my mother board GA-Z270-HD3 slots (SATA Express SATA3 1,0) & (SATA3 2,3,4,5), I connected data cables both SSD and hard drive into the first one which is (SATA Express SATA3 1,0) as before the hard drive data cable was connected into second one which is (SATA3 2,3,4,5). Now data cables for both are connected into the first one (SATA Express SATA3 1,0), but still does not read D drive. Any suggestions please thank you