A user has acquired an AMD Ryzen 9 7950X3D CPU which allegedly features 3D V-Cache stacks on both Zen 4 core dies. AMD's Ryzen 9 7950X3D CPU With Up To 192 MB Cache Spotted In Dual CCD 3D V-Cache Boosted Design, Could Be A Software Reporting Issue or Rare Engineering Sample According to a video published at Bilibili, a user has reportedly got his hands on an AMD Ryzen 9 7950X3D CPU with 192 MB of L3 cache onboard, which is 64 MB more L3 cache than the standard chip. Related Story AMD Instinct MI300A APU With CDNA 3 GPU, Zen 4 CPU & Unified Memory Offers Up To 4x Speedup Versus Discrete GPUs In HPCWhile it isn't sure whether the change made within the L3 cache was an actual one, upon testing the processor at CPU-Z as well, it showed the exact 192 MB figure, which meant that it might be a permanent change, but there are other theories to this modification as well, which we will discuss later on.
Now, the possibility of a 192 MB L3 cache on the Ryzen 9 7950X3D CPU isn't entirely out of the equation, as it is possible by tinkering with the chiplet configuration.
To achieve such a config, both Zen 4 CCDs featured on the Ryzen 9 7950X3D will need to have 3D V-Cache stacks of 64 MB. The two CCDs featured on the chip already feature 64 MB of L3 cache (32 MB per CCD) and a single 3D V-Cache stack provides 64 MB of additional cache.
So far, all of AMD's Ryzen X3D CPUs have come with a single 3D V-Cache stack. Such configurations offer up to 192 MB of L3 cache (64 MB from the Zen 4 CCDs and 128 MB from the 3D V-Cache stacks).
it is essential to note that while increased cache memory may result in a huge performance improvement, it might be difficult for manufacturers to lay down cache stacks, since it disturbs the cache uniformity, ultimately leading to higher latencies in gaming and professional performance.