Zen 2 mem controller isnt bad
It's extremely poor in latency like i have 63ns on my Zen 2 chip and with the same memory i would easily get 38ns on Intel(75% less latency). That's a MASSIVE difference their memory controller is only good for bandwidth and nothing else and a lot of applications benefit from low latency memory for example games.
1usmus and Stilt both say Amd is using very old memory controllers another area of proof is 14cas latency barely does anything at 3600mhz memory over the memory controller just not being able to handle it. I get around 65ns at 16cas timings vs 63 with 14 for example.
Not to mention in terms of pure brute forcing it can't handle speeds like Intel can either, Bullzoid tried
People have tried everything too and the best i've seen over 1000 pages of material on the memory overclocking forum is 61ns and that is with a 3950x and 14 cas latency at 3800mhz. Not sure how low Intel's can get but i know its almost twice as good in terms of latency
Edit Amd knows this too which is why they through a massive L3 cache at Zen 2 to hide the memory controller latency