I wish you would have tested how you should set memory settings for a given memory. You obviously had very high quality memory because you were able to run 4000 MHz CL15. However, the more interesting question would have been: are you always better with higher frequency + higher latency or should you turn frequency down to allow reducing the latency. At least high quality motherboards allow configuring the same memory sticks to prefer low latency or high frequency.We measure the impact that memory frequency has on the Chia plotting process.
Chia Coin RAM Guide: The Best Memory Settings for Plotting : Read more