The AMD EPYC Milan-X server CPU platform has a layered L3 cache, which significantly increases the amount of available cache, bringing it towards max 768MB.

AMD Milan-X, which was first spotted by ExecutableFix in May, is a server CPU family that takes advantage of AMD's latest X3D packaging technology, according to the company (3D V-Cache). According to the most recent leak, it would combine AMD Genesis-IO die and stacked chiplets with a vast third-level cache, maybe up to 768MB.

Executable Fix (via videocardz) provides up-to-date information about the series, including the full specifications of the AMD EPYC 7003 CPUs, as well as links to other useful resources. According to the leaker, the flagship Milan-X processor, codenamed 7773X, will have 64 cores and 128 threads with a total power consumption of 280W. This CPU, along with the other 'downgraded' components, would have 768MB L3 cache, which is over three times the amount of L3 cache found in the original Milan series (up to 256MB). The specifications for the 7573X, 7473X, and 7373X were also revealed. The core counts for these SKUs would be 32, 24, and 16 cores, respectively. TDP would be 240W, however, the L3 cache would be 768MB on both the 7473X and 7373X.

In this case, the 768MB L3 cache shows that each Core Complex has 32MB, similar to the original Milan configuration, but the 64MB V-Cache is linked to each CCD. That is, each processor has 8x32 MB of main memory plus 8x64 MB of virtual memory. In contrast to AMD's Ryzen processors, which include 3D VRAM, the Milan-X series has not been officially confirmed.

AMD EPYC Milan-X specifications leak, revealing up to 64 cores, 280W TDP, 768MB L3 cache.