Normal
It's because you have to enable "OC" profiles in them. Just about any decent board will enable to higher clocked profiles. I wouldn't spend more than 10% more for fast RAM, than decent speed RAM. You hit diminished returns pretty quick. Slower RAM mostly bottlenecks high end GPU (1080 class) and high FPS. It's returns is greatly diminished when you have a 1060-1070 performance.https://www.gamersnexus.net/hwreviews/3086-intel-i5-8400-cpu-review-2666mhz-vs-3200mhz-gaming/page-4
It's because you have to enable "OC" profiles in them. Just about any decent board will enable to higher clocked profiles. I wouldn't spend more than 10% more for fast RAM, than decent speed RAM. You hit diminished returns pretty quick. Slower RAM mostly bottlenecks high end GPU (1080 class) and high FPS. It's returns is greatly diminished when you have a 1060-1070 performance.
https://www.gamersnexus.net/hwreviews/3086-intel-i5-8400-cpu-review-2666mhz-vs-3200mhz-gaming/page-4