I'm running G-Skill Trident Z ddr4 3200 at 3066 on Asrock X370 Gaming X. Their QVL says it will only run at 2933mhz, but with the new 3.50 Bios and then the upgrade Bios to 4.50, it seems very stable at 3066mhz. No problems yet. And with an overclock of 4.0 on the Ryzen 1700X, its very fast...