I use G.Skill Flare DDR4-3200 CL14 as it was designed for Ryzen and one of the few kits guaranteed to work with all first generation Ryzen processors and boards, but due to design improvements with the Ryzen 3000 series (Zen 2), RAM speed doesn't have as much effect as it did before, and 3200 CL14 is really the sweet spot, which I believe AMD also said in one of their EPYC presentations. The 2x8GB G.Skill Flare CL14 kit is also $125, which is cheaper than the Trident Z kit, though it lacks some of the eye candy.
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