AMD announced via a community update that its new v18.104.22.168 AGESA (AMD Generic Encapsulated System Architecture) is available for motherboard vendors. AGESA is a bootstrap protocol that initializes processor cores, memory, and the HyperTransport (now Infinity Fabric) controller. Motherboard vendors build firmware upon the AGESA bedrock, so improvements to the underlying code allow manufacturers to provide more options through their own firmware.
Like most new chipsets based on entirely new processor architectures, the initial wave of AM4 motherboards were a bit rough in the firmware department. That improved quickly as motherboard vendors issued a flurry of updates in the early weeks after launch, but Ryzen's memory overclocking and compatibility updates lagged behind some of the more important issues. We have seen compatibility improve over time, but we've eagerly awaited AMD's promised AGESA update that unlocks more memory settings.
The new AEGSA code adds 26 new memory parameters that should improve memory compatibility and overclocking. Overclocking memory above the default settings is of particular importance for Ryzen processors. The new CPUs feature two four-core CCX (Core Complex) that communicate via AMD's Infinity Fabric. As we've seen in our testing, increasing the memory transfer rates reduces the Infinity Fabric's latency, which in turn increases performance.
Recent firmware updates already exposed the ProcODT setting (a memory signal termination value), and we've found that altering this setting between 40-60Ω helps memory overclocking tremendously. The new AGESA update unlocks even more granular controls that should allow us to surpass the 3200 MT/s barrier without adjusting the BCLK frequency. As Wizerty demonstrated in our How To Overclock AMD Ryzen CPUs article, manipulating the BCLK frequency can provide unexpected results, such as rolling the motherboard back to PCIe 2.0. The new memory multipliers now allow up to DDR4-4000 without adjusting the BCLK frequency.
Gigabyte and ASUS have already entered the public beta stage with firmware based on the new AGESA code (GA-AX370-Gaming 5 and Crosshair VI, respectively).
The update also brings improved virtualization capabilities:
If you’re the kind of user that just needs (or loves!) virtualization every day, then AGESA 22.214.171.124-based firmware will be a blessing for you thanks to fresh support for PCI Express Access Control Services (ACS). ACS primarily enables support for manual assignment of PCIe graphics cards within logical containers called “IOMMU groups.” The hardware resources of an IOMMU group can then be dedicated to a virtual machine.This capability is especially useful for users that want 3D-accelerated graphics inside a virtual machine. With ACS support, it is possible to split a 2-GPU system such that a host Linux® OS and a Windows VM both have a dedicated graphics cards. The virtual machine can access all the capabilities of the dedicated GPU, and run games inside the virtual machine at near-native performance.
Ryzen's gaming performance has been a moving target as a wave of new firmware and chipset drivers, not to mention game patches and the new power plan, have steadily improved the outlook. That's led to a lot of late-night re-testing in our labs, but performance is definitely headed in the right direction.
AMD expects validated BIOS based on the newest AGESA code to arrive in mid to late June, depending upon the qualification requirements of the respective vendors.