So I recently got a new motherboard that can run up to 2133 MHZ RAM. I only got 8 GB of it and I still have 16 GB of 1600 MHZ RAM. If I add 2 sticks of 2133 MHZ and 2 sticks of 1600 MHZ RAM in my motherboard, will they run at separate speeds (2133 and 1600) or will the faster RAM downgrade?