AMD X399 board quad mem

[Randy6309]

I have tried to get all 4 channels going no matter what I do when I install 4th. Stick to get all 4 Mem channels going
It drops a channel.
All the slots are good and all Memory is good.
any advice?

My only thought is more voltage to run all 4 channels

 

[pendragon1]

more voltage

 

[lopoetve]

SoC Voltage. Bump it up. Also try lower speeds - the first gen Threadrippers were picky as fuck about memory, just like first gen Ryzen, and some won't get to higher speeds no matter what you do. I've got a 1950X that maxes at 2666 no matter what I feed it.