Will take another try at this. Few days ago I posted that my 7 gtx 1060 machine will only find 3 of the cards with win7 ult64 os.  I decided to try this with ubu 16.04 as well with the same issue. This points to maybe a  MB setting as opposed to an OS setting. Can anyone shed a light on how to make all cards show up?  Both MB Asus  H270 and Z270

Will be adding a MSI Z170A as well when the cards and risers show

thaelin