Check this video https://www.youtube.com/watch?v=nJZIGUaEXvU
I was able to get 4.5Ghz on all cores at v1.2. Using CTR with Hybrid OC is also a nice aproach or just use it to find your CPU limits.
I have settled on 70 amps. I added workers to prime until the all core frequency dropped below my manual all core oc. Seems to be working well.