Infinity fabric speeds appear to scale substantially better on Renoir. A user over on the Chiphell forums posted screenshots and proof that appear to a Renoir chip running with the Infinity Fabric FCLCK set to a blistering 2100 MHz. To put this in comparison, desktop Ryzen 3000 chips tend to top out at 1800 MHz on the Infinity Fabric, the main reason why AMD recommends 3600 MHz DDR4 as the “sweet spot” for CPU performance (since Infinity Fabric clocks and memory clocks are coupled til that point).
The higher Infinity Fabric clockspeeds are a good sign because at higher FCLCK, the Infinity Fabric interconnect mitigates the latency penalty inherent in AMD’s chiplet-based design. While Renoir is built on a monolithic die, the CCXs on a single CCD still share resources across the Infinity Fabric. Higher FCLK means substantially higher access speeds.
Enhanced Infinity Fabric capabilities should help AMD cement its gains in the mobility segment. Recently, a Lenovo marketer went out in the open to claim that Intel was unable to keep up with AMD on account of Renoir, following price cuts to Intel’s Core i7 Comet Lake H lineup. Faster IF speeds and the possibility of FCLCK overclocking should offer even more value to buyers looking to get their hands on parts like the Ryzen 7 4800H.