Not really. So the Epyc is basically 4 ryzens. So you get 4x the cores, 4x the memory channels, and 4x the pieces of silicon. So think of a single socket ryz

Not really. So the Epyc is basically 4 ryzens. So you get 4x the cores, 4x the memory channels, and 4x the pieces of silicon. So think of a single socket ryzen as a quad socket motherboard. In either case you have clusters of cores/cache connected to memory controllers and hypertransport. For most workloads a NUMA aware kernel does a pretty good job of minimizing hitting pages on other controllers. But it's not a particularly big deal when you miss, typically about 10% (latency and bandwidth). AMD makes all the I/O pins capable of hypertransport (or whatever they call it now) and PCI-e. This isn't particularly new btw. MCM (multiple chips per package) go way back to the pentium pro if not before. Intel Xeons are all single chip, but have similar on chip architectures. The 4,6,8 core chips are pretty simple, but the larger core chips have a ring bus for one set of cores, and another ring bus for the second. But generally for most workloads the NUMA issues related to the newer chips isn't a particularly large hurdle from getting good performance. What I am concerned about though is how good the Epyc floating point is, I fear they are bragging about integer performance and not FP because they are behind on FP.