Otto have the main idea, let's try to explain it a bit more. This is a very common question, unfortunatly there is no real fix.
Your CPU have a base speed and your memory have another base speed.
In this case, the CPU base is 1333 so your memory will run slower because if she run faster than the CPU, this will lead to error. So unless you Overclock your CPU to around 3.9 or 4.0Ghz, your ram may fail to run at 1600. To use a simple exemple. When you run water from a pump into a smaller tube, she get stuck and can only get out at the tube rythm. If you want the water to go at the pump speed, you have to get a bigger tube. Is it better now?
Martin_metal_88
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