Ryzen 3000 memory controller has "half the performance" on single CCD CPUs | Page 2 | TechPowerUp Forums
Some memory speed benchmarks with a Ryzen 1700 @ 4.0GHz and a 1080 Ti, 2666 Auto vs 3200C14 vs 3466C14 tweaking sub-timings. Timings and settings used in the comments. : r/Amd