In the Ryzen 3000 test, we only briefly tried how well AMD’s processors respond to faster memory. A very elaborate article from the Romanian hardware site Lab 501, which is also available in English, dealt in detail with the RAM scaling of the CPUs. According to the colleagues, DDR4-3733 with CL16 latencies is currently the ideal configuration for systems suitable for everyday use, as throughput and access time are better compared to the standard clock.
AMD delivers the chips with DDR4-3200 support, at least as long as a single-rank module is used per memory channel. We have all done our benchmarks with CL14-14-14-34-1T, which already leads to very good results. If the clock rate is increased, the latencies usually increase, which is why Lab 501 set CL16-16-16-36-2T for DDR4-3733. However, the Zen(-2) architecture has a special feature: The clock of the memory is coupled to that of the RAM controller, which in turn is coupled to the Infinity Fabric, which links all chip components together.
If the frequency is set from DDR4-3200 to for example DDR4-3600, the memory controller and fabric work with 1,800 MHz instead of 1,600 MHz and the processor is also accelerated internally. The CL16 settings also reduce the absolute latency of the memory subsystem compared to DDR4-3200-CL14, which also increases performance. With DDR4-3733 the fabric should actually work with 1.866 MHz, but not all CPUs reach this clock rate and a synchronous instead of asynchronous frequency provides better results anyway.
The difference between DDR4-3200-CL14 and DDR4-3733-CL16 with corresponding RAM controller and fabric clock is comparatively small, but in some benchmarks and real applications the increase is more than 10 percent. Games can also benefit from the minimum frame rate, although the average Fps do not increase. Those who want to use DDR4-3733-CL16, however, need memory modules with very good B-Dies from Samsung or excellent chips from Micron or SK Hynix, which makes the sticks expensive. 16-GByte-Kits like G.Skills Trident Z Royal cost at least 200 Euro.