This should be it, but if (I don't recall Asus having this problem but I could be wrong) it forces non-1:1 IF to strictly 2:1 then you may have to dig into the CBS or OC menus to find the dividers section:
View attachment 183658
I needed somewhere in the ballpark of 1.8V to bench my 4400 16-16-16 1:1 result in AIDA, on my 4650G. Even with decent B-die you're probably looking at somewhere around 1.65V at the very very least.
If sticking to 1.5-1.55V max, 4000 or 4133 16-16-16 is probably a better bet for a stable daily setup, but you don't have a Renoir, so the performance just isn't there above 1900MHz IF, pretty pointless.