Okay, so my new RAM arrived today and I was itching to see how fast I can make it run with the Ryzen 5 3400G. The RAM I got is 3600 MHz CL16-16-16 (Samsung B-Die, I believe). I couldn't get the system to boot at 3600 MHz, and anxiety demanded that I don't try 3400 either, so I settled at 3200 MHz CL16 and it runs fine. The boost in 3DMark Firestrike graphics test was around 18% from RAM alone, which is fairly significant. I think everyone knows the Ryzen "Processors with Graphics" are heavily memory bandwidth limited, so this was to be expected.
Anyway, I am playing at 1080p, but with 80% resolution scale, and TAA Sharpening to make up for the blurriness, at least a bit. I think it works quite well.