After several hundred appeals from the community ( and unofficial support from board partners), AMD has officially announced support for the Zen 3 processor family on 300 series motherboards, including the X370, B350, and the A320 chipsets. This news comes with the Ryzen spring update, comprising of the 5800X3D and budget Zen 3/Zen 2 SKUs.
AMD plans on launching seven new processors, three based on the Zen 2, three on the Zen 3, and lastly the Ryzen 7 5800X3D. The Ryzen 3 4100, Ryzen 5 4500, and the 4600G will form the new Ryzen 4000 desktop lineup and will be compatible across the 300, 400, and 500 series motherboards. Meanwhile, the Ryzen 5000 family, in addition to the Ryzen 7 5800X3D will be compatible with the 300 series boards, including the paltry A320 chipset. The AGESA update enabling the same is slated to roll out in April, around the same time as the new processors.