AMD has released the latest version of AGESA microcode for the Socket AM5 platform, version 1.0.0.3, which makes relevant adjustments for the Ryzen 7000 series processors based on the Zen 4 architecture, which is the first update since the release of the new platform.
Notably, the new version reintroduces a “Precision Boost C-State Limiter” that prevents CPU cores from being boosted above 5.50GHz when more than 4 cores are active (heavy load operation).
From SkatterBencher’s demo, the performance of high-end AMD Ryzen 7000 series desktop processors may be affected to a certain extent, but the impact is very limited.
▲ NopBench is a program developed by ElmorLabs that calculates the maximum frequency that can be obtained with the workload of the CPU cores (from 1 to n threads).
NopBench measures the number of NOP instructions that can be processed per second with the help of NOP instructions. To make NOP throughput comparable between processors of different microarchitectures, it also uses an architecture-specific factor, which is equal to 2.5 for “Raphael”.
By comparing the NOP throughput of Ryzen 9 7950X processors tested with AGESA 1.0.0.2 through 1.0.0.3 (ASUS ROG Crosshair X670E Extreme BIOS versions 0611 and 0705), SkatterBench concludes that
In the original 0046 or 0611 BIOS versions, the Ryzen 9 7950X processor can reach around 5.7GHz on all 16 cores, and when upgraded to the 0705 BIOS version based on the AM5 AGESA 1.0.0.3 microcode, the maximum frequency is only between 5.4GHz and 5.5GHz.
SkatterBencher concludes with six points, which are
Enabling C-State is the preferred option, originally because it provides higher performance for AGESA 1.0.0.2/1.0.0.3.
AGESA 1.0.0.3 microcode reintroduces the “Precision Boost C-State Limiter”, which was not present on the first motherboard and BIOS releases.
When more than 4 cores are active, the processor frequency is only up to 5.5GHz, which means that some Ryzen 7000 series processors may experience performance loss.
On motherboards with this option, simply enable “Medium Load Boostit” to bypass the limitation.
On motherboards without this option, asynchronous eclk provides the only viable overclocking strategy to get the processor frequency above 5.5GHz.
The actual performance limits imposed by the “Precision Boost C-State Limiter” are small, as users need at least one processor with multiple cores capable of running above 5.5GHz, and in fact most workloads are likely to trigger other limits, thus limiting the processor’s operating frequency. In fact, most workloads are likely to trigger other limits, thus limiting the processor operating frequency.+
