ASUS B350 Prime+, getting all 4 DIMMs to work

scuzzycard

Honorable
So I just put a new system together for my son, and gave the Ryzen a try. Very pleased so far, but I was hoping to reuse my 4X4GB Crucial Ballistix Sport DDR4-2400 BLS4G4D240FSA.8FARG that I had sitting around. They were originally a quad-channel 16GB X99 kit which I used for a couple of months before upgrading that machine to 32GB. In the Ryzen machine, I can only get it to work with 2 modules installed. It will only POST with 4 modules if they are installed in a particular order, and even if it POSTS, it won't make it to the Win10 desktop. I tried setting the RAM for 2133 and then 1866, but that didn't help. Any tips or tricks?

ASUS Prime B350 Plus
AMD Ryzen 7 1700 w/ stock cooler
Seasonic 620W Bronze
Zotac GTX 1070 FE
Samsung 850 EVO 500GB m.2
Western Digital Purple 2TB
Windows 10 Pro