At this point, if you have been following what AMD has been doing with its CPUs, you may know the entire stack of CPUs, from Ryzen 3 to Threadripper and Epyc, are all using the same Zeppelin die, with binning deciding where the dies. Those Zeppelin dies feature eight cores between their two core complexes (CCXs), 32 PCIe 3.0 lanes, and dual-channel memory support. By disabling cores we get the six core and four core parts, but by leveraging Infinity Fabric, AMD is able to combine multiple dies to create the Threadripper and Epyc chips, with up to 32 cores, 128 PCIe 3.0, and eight-channel memory. Some quick math there shows the Epyc chips are using four Zeppelin dies, and with Threadripper having 16 cores, 64 PCIe lanes, and quad-channel memory support, it uses two dies. When it was discovered Threadripper chips are hiding apparently four dies under the IHS, there were questions about the status of those other two dies, so der8auer decided to take a (second) look on his YouTube channel.
Initially der8aurer had put up a video where he delidded a Threadripper to find these four dies, but was asked to take it down for a bit, as the chip he used was an engineering sample. Now he has a new video up because there have been some claims that two of those dies are 'dummies' and are just spacers, even blank silicon. This time, instead of just popping off the IHS, der8auer went further to remove the dies from the packaging and then remove layers from the die to see if there were circuits underneath.
It turns out those claims of the dummy or blank dies are apparently false, as all four dies der8auer pulled out did in fact have circuitry in them; they are not dummies. They are definitely disabled though and likely defective, because why would you waste a usable die or silicon?
Source: der8auer YouTube
Back to original news post