AMD today posted an updated compatibility list of DDR4 memory kits for Ryzen processors. While just about any DDR4 memory kit will run on socket AM4 motherboards, a limited few have been tested by AMD to run reliably at speeds such as DDR4-3200, DDR4-2933, DDR4-2667, and DDR4-2400. AMD's new compatibility list contains a wider selection of DDR4 memory modules that have been tested by AMD to work reliably on Ryzen processors.To make the most of these modules, however, AMD asks you to look out for and install motherboard BIOS updates which contain the AGESA 1.0.0.6 micro-code update. This should be prominently displayed in the change-logs of BIOS updates from motherboard manufacturers, and the latest batches of motherboards should come with AGESA 1.0.0.6 pre-installed.The revised DDR4 compatibility list can be accessed here DDR4 memory speed has a significant impact on performance of Ryzen-powered machines beyond just added memory bandwidth. The clock speed at which the chip's internal InfinityFabric link ticks, is proportional to DRAM clock. This interconnect links the two quad-core complexes (CCXs) on the 14 nm "Summit Ridge" silicon on which the Ryzen socket AM4 processors are based. Among additions to AMD's revised memory compatibility list are brands that aren't necessarily based on Samsung b-die DRAM chips.