As part of a novel approach to integrating ever-greater amounts of L3 cache on their Ryzen processors, AMD announced in June 2021 that some Ryzen 5000-series Zen 3 CPUs would 'in the future' be released released with 3D V-Cache. The concept was expounded upon by Dr Lisa Su at CES 2022, where the first of these chips bound for retail was unveiled.
The Ryzen 7 5800X3D will be a variant of the 5800X with an extremely beefy 64MB of additional 3D L3 cache integrated as a stacked layer and supported through silicon vias rather than conventional traces. As a result the footprint of the chip doesn't increase (and some additional engineering ensure that the overall package Z-height is unchanged), but the total available L3 Cache on the processor is increased from 36MB to a huge 96MB. A Zen 3 processor with two CCD's could in theory support up to 192MB of L3 Cache, but thus far that isn't on the horizon as a consumer option.
The processor was announced with a Spring 2022 release window, plugging the product release gap until Zen 4 AKA the Ryzen 7000-series later in the year. This week component manufactuer GIGABYTE once again threw the spotlight on the chip by releasing BIOS updates to support the processor; not just for their AMD 500-series motherboards, but also older B450 and X470 models. Updating the BIOS will make the new processor a drop-in upgrade, but it could come at the cost of sunsetting support for older chip generations.
These new UEFI BIOS releases incorporate AGESA 220.127.116.11B, unlocking 'future CPU support' (i.e. the 5800X3D) and likely also adding some bug fixes for performance issues that cropped up with release 18.104.22.168.
The timing could indicate that the processor is expected sooner rather than later (Spring officially starts on March 22nd), and AMD fans will likely be hoping for sooner. With an anticipated uplift of 15% aggregated across a wide range of workloads, the 5800X3D looks set to take the fight to Intel's Alder Lake chips.