A new HWBot entry has proven what some thought impossible years ago: AMD apparently features the best memory controller in the x86 consumer space. A user going by the alias Bianbao XE achieved a 6,666 MHz frequency on a single stick of Crucial Ballistix Max. The stick's original rating is for a mere 2,666 MHz - doesn't that put things in perspective?

Another thing that puts things into perspective is that the support for such an overclocking feat was a ROG Strix B550-I Gaming motherboard (min-ITX means smaller tracing distance between CPU and memory, and thus higher signal integrity) paired with none other than AMD's Ryzen 7 4700GE 'Renoir'. The APU was underclocked and overvolted - a technique that aimed to increase stability of the memory controller whilst also reducing operating temperatures (balancing the higher voltage and lower frequency). Of course, memory timings were loosened to achieve this feat (timings of 30-27-27-58 aren't what you'd usually like to see), but then again, this wasn't meant to power the utmost memory performance - only the highest frequency. And that was definitely achieved.

AMD's 7 nm "Renoir" APU silicon, which features eight "Zen 2" CPU cores, has only a quarter of the L3 cache of the 8-core "Zen 2" CCD used in "Matisse," "Rome," and "Castle Peak" processors, with each of its two quad-core compute complexes (CCXs) featuring just 4 MB of it (compared to 16 MB per CCX on the 8-core "Zen 2" CCD). Chinese-language tech publication TecLab pubished a quick review of an alleged Ryzen 7 4700GE socket AM4 processor based on the "Renoir" silicon, and discovered that the chip offers significantly lower memory latencies than "Matisse," posting just 47.6 ns latency when paired with DDR4-4233 dual-channel memory.

In comparison, a Ryzen 9 3900X with these kinds of memory clocks typically posts 60-70 ns latencies, owing to the MCM design of "Matisse," where the CPU cores and memory controllers sit on separate dies, which is one of the key reasons AMD is believed to have doubled the L3 cache amount per CCX compared to previous-generation "Zeppelin" dies. TecLab tested the alleged 4700GE engineering sample on a ROG Crosshair VIII Impact X570 motherboard that has 1 DIMM per channel (the best possible memory topology).