I'm getting stable 2400 on corsair default timings with Vengeance® LPX 16GB (2x8GB) DDR4 DRAM 3200MHz C16 Memory Kit – Cool Gray (CMK16GX4M2C3200C16S) but cant get any higher than that. Its a samsung dual rank kit.
Mother board: Asus X370 Prime Pro, 0515 bios
Processor: Ryzen 1800X
Ram kit: CMK16GX4M2C3200C16S _ Corsair Vengeance LPX 2x 8gb 3200 mhz
Bios timings: 16-18-18-18-36, 1.35v
Let me know if you need more testing or screenshots of the kit/siv etc. I've tried every timing I could think of and cannot get above 2400. Its dead solid at 2400 though, so its better than 2133!