I don't know MSI either but RandomX isn't dependant on DRAM speed so it's a waste of time to tweak it.
Don't spread lies. It is dependant on RAM speed and latency, we're talking about the difference between 12 kh/s and 15 kh/s on 3900X.
I'm willing to try with cl 14 and 2666mhz to see how it goes. I know for a fact that bandwidth is more important than latency for most use cases, for mining monero I have no idea.