Here’s What A Ryzen 7 7800X3D Looks Like With An Infrared Camera

chip detective @FritzchensFritz posted something great image comparison We feature shots taken with an infrared camera between the Ryzen 5 7600 and the Ryzen 7 7800X3D. An infrared image shows the internal layers of AMD’s Ryzen 7000 and 7000X3D processors, revealing subtle architectural differences between the different chips.

The difference between both CPUs can be hard to spot at first glance, but once you know what to look for, the differences are clear. The CPU on the left of the image represents the Ryzen 5 7600 (and Ryzen 7 7700), while the one on the right represents the Ryzen 7 7800X3D.

A closer look at each CPU’s Core Complex Die (CCD) (lower right die) reveals how AMD has laid out the cores and cache layout in their Ryzen 7000 processors. The four “squares” on the left and right edges of the CCD represent the eight physical Zen 4 cores on the chip, while the middle section holds the CPU cache.

The Ryzen 5 7600 is a 6-core part, but thermal imaging shows that the chip physically has 8 cores. This is because AMD (for now) only uses 8-core clusters on their Ryzen chips and will disable cores when they need to make additional his SKUs.

The middle part of the CCD represents the CPU cache area where the L1, L2 and L3 caches are located. Here we can see a clear change between the 7600 and the 7800X3D. The 7600 features a regular L3 cache configuration consisting of two 16MB caches merged into one 32MB cluster, while the 7800X3D has a “huge” 64MB cache slab on top of the bottom 32MB cluster. It looks completely different because it’s stacked (hence the 32MB cluster at the bottom). You can learn more about this setup in our article AMD shares details of new 2nd Gen 3D V-Cache chiplet with up to 2.5 TB/s.

The infrared image also shows that the stacked 64MB cache partially covers the Zen 4 core as well due to the lithography difference between the 7nm SRAM 3D-VCache and the 5nm Zen 4 CPU core. This differs from AMD’s first generation 3D-VCache CPU, the Ryzen 7 5800X3D. The Ryzen 7 5800X3D featured an even layer of stacked cache that only covered the lowest 32MB L3 cache cluster and didn’t cover the cores. All three cores use the same 7nm lithography.

The Ryzen 7 7800X3D’s uneven 3D-VCache doesn’t affect performance as far as we know, but it was necessary for AMD to move the TSV connector (which powers the 3D cache) out of the L3 cache die area. posed additional engineering challenges. Old Zen 3 designs are stored in his L2 cache area on Zen 4 chips. Ironically, the 7800X3D’s 3D-VCache chip is actually smaller and denser than the 5800X3D’s, but the 7800X3D’s CCD is still too small and the new 3D-VCache chip can’t fit within the die constraints given for L3 cache only. does not fit in