this is how I planned to have my computer build, "1 SSD for the OS and applications, 1 SSD for working docs and maybe a game or two. HDDs for mass storage and backup files." but I am unable to get the computer to recognise the 4TB WD Black HDD. the two 960 pro SSD are operational. What do you do in bios to get the HDD visible, or do I have to change settings somewhere else.