I have a mother board that has memory specs of 4 slots and is duel channel, max 4GB per slot and 16GB total RAM. I currently have a 8GB (2x4GB) RAM kit on the board. If I were to buy an an identical kit to the 2x4GB kit I have would it be considered "in spec" to put them in and make it 16GB or would I need to buy a whole new 16GB kit