AMD Adds Further Zen 4 CPU Support In Linux Patches, Enables RDDR5 & LRDDR5 For EPYC CPU With Up To 12-Channels


AMD is rolling out the first enablement patches of their next-generation EPYC Zen 4 CPUs and the new features incorporated within them for the Linux OS.

AMD Zen 4 Enablement Patches Rolling Out To Linux, Bring RDDR5 & LRDDR5 Memory Support

While AMD still isn't finished with Zen 3 on both client and server platforms, AMD's Linux team is already rolling out the initial patches for Zen 4 support in the Linux OS. As reported by Phoronix, the latest patches include support for AMD's next-generation EPYC server chips that will offer 12-channel memory support.

Graphics Card Shipments To Improve Considerably By Summer of 2022, Report States Citing Improved ABF Substrate Capacities

AMD already rolled out patches that enabled support for AMD EPYC CPUs with up to 12 CCDs so this means that Linux currently has both Genoa and Bergamo added to the list. There's also new temperature monitoring support for Zen 4 CPUs & the latest patch further expands on the memory front.

The new patch brings support for up to 12-channel memory in both RDDR5 and LDDR5 flavors. The RDDR5 (Registered DDR5) & LRDDR5 (Load-Reduced DDR5) memory will both be supported by the AMD EPYC Zen 4 platforms with LRDDR5 aimed at dense memory servers. Each CPU will feature up to 12 memory controllers (per socket) which is an upgrade from the existing 8 controllers per chip. It is also reported that AMD's Zen 4 chips will be branded under the 'Family 19h Models 10h-1Fh and A0h-AFh'.

The EPYC Genoa chip renders revealed a total of 12 CCD's (16 cores per CCD) to reach 96 cores while the AMD Bergamo renders also show 12 CCDs but it is likely that either Zen 4C houses more cores per CCD or the render shown wasn't final as a 16 core CCD configuration would mean a total of 16 Zen 4 CCDs to hit 128 cores. The final die arrangement is definitely going to be an interesting sight. You can check out more information on both next-gen AMD EPYC CPU families that are launching with Zen 4 & Zen 4C cores in 2022 & 2023, respectively, here.

AMD EPYC CPU Families:

Family BrandingEPYC 7001EPYC 7002EPYC 7003EPYC 7003X?EPYC 7004?EPYC 7005?EPYC 7006?
Family Launch2017201920212022202220232024-2025?
CPU ArchitectureZen 1Zen 2Zen 3Zen 3Zen 4Zen 4CZen 5
Process Node14nm GloFo7nm TSMC7nm TSMC7nm TSMC5nm TSMC5nm TSMC3nm TSMC?
Platform NameSP3SP3SP3SP3SP5SP5SP5
SocketLGA 4094LGA 4094LGA 4094LGA 4094LGA 6096LGA 6096LGA 6096
Max Core Count3264646496128256
Max Thread Count64128128128192256512
Max L3 Cache64 MB256 MB256 MB768 MB?384 MB?TBDTBD
Chiplet Design4 CCD's (2 CCX's per CCD)8 CCD's (2 CCX's per CCD) + 1 IOD8 CCD's (1 CCX per CCD) + 1 IOD8 CCD's with 3D V-Cache (1 CCX per CCD) + 1 IOD12 CCD's (1 CCX per CCD) + 1 IOD12 CCD's (1 CCX per CCD) + 1 IODTBD
Memory SupportDDR4-2666DDR4-3200DDR4-3200DDR4-3200DDR5-5200DDR5-5600?DDR5-6000?
Memory Channels8 Channel8 Channel8 Channel8 Channel12 Channel12 ChannelTBD
PCIe Gen Support64 Gen 3128 Gen 4128 Gen 4128 Gen 4128 Gen 5TBDTBD
TDP Range200W280W280W280W320W (cTDP 400W)320W (cTDP 400W)480W (cTDP 600W)