Hi i have 6 memory slots on a rampage III gene motherboard 3 red 3 black i purchase 2x8gb same memory spec as there was 3x2gb already on board. When i add the 2 x8gb it does not read it and i loose a 2gb stick system showing 4gb total.When i install 2x8gb on there own its fine it shows 8GB usable then i add the 3x2gb together or one by one and it will not read the memory and reduces the 8GB to 6GB strange any one had this issue before and where am i going wrong?