Where you are you reading that ram rating in dram calc? I'm using Ryzen calc 1.7.3vMy kit is also the 3000cl15 Usually the avg rev E can do 300ns, mine does 280. You can probably do anywhere from 530 to 580 depending on bin. Do you have agesa 188.8.131.52b? Before that I was stuck at 3733 getting random reboots, after 3800 worked fine.
Talking to cellar door or me? He's on ryzen 3000 which rarely can do more than 3800. I can do 4133, I might be able to do 4200+, but it would require way to much soc voltage for my comfort. I need 1.12V for 4000, 1.18V for 4066 and 1.25V for 4133. I bet 4200 would need atleast 1.32V. 1.2V is by many considered upper safe limit.
My MB is cheap, but it has only 2 dimms (helps a lot with ram oc compared to 4) and is rated for 5100MHz ram on Ryzen 3000, max 4600 on Ryzen 5000 which makes little sense...
AAs for ram oc I'm limited by bad bin ram, it has a 94% rating on dram calc, making it sub avg compared to other B-die. 1T and liw tRCDRD is very hard, trfc won't go below 141ns at 1.46V. The rev E I had was 102% rated so it beat the majority of rev E.