AMD Ryzen 9 5900X3D sample appears online: 128MB cache on unreleased Zen 3 CPU

An unreleased Ryzen 9 5900X3D has shown up on the Chiphell forums as a rare engineering sample, offering a look at a late pre-release Zen 3 chip for AM4 that AMD never ended up selling at retail.

CPU-Z Download

What stands out is the cache setup. Earlier prototype demos of the Ryzen 9 5900X3D and Ryzen 9 5950X3D pointed to 192 MB of total L3 cache, but this sample is reportedly configured with 128 MB split between 32 MB and 96 MB. Based on the Chiphell listing, that likely means only one of the chip’s two CCDs has 3D V-Cache.

The rest of the spec still looks familiar on paper: 12 cores, 24 threads, AM4. But the screenshots posted on Chiphell show boost clocks around 4.65 GHz in CPU-Z and as high as 4.73 GHz elsewhere. That’s above earlier dual-V-Cache samples, which were said to top out closer to 4.4 GHz. One possible reason is that AMD was juggling performance, thermals, voltage limits, and the added manufacturing complexity at the same time.

For anyone who keeps an eye on AMD hardware, this one is worth tracking. It suggests AMD tried more than one X3D approach before it settled on releasing only the Ryzen 7 5800X3D, then later came back to the single V-Cache CCD idea in newer multi-chiplet designs.

The Chiphell post includes the listing and screenshots, though this older motherboard BIOS just to boot and, according to the forum post, was never ready for retail.

AMD Ryzen Master Download