AnandTech compared Intel's Skylake-SP chips to AMD's Epyc chips [anandtech.com]:
We can continue to talk about Intel's excellent mesh topology and AMD strong new Zen architecture, but at the end of the day, the "how" will not matter to infrastructure professionals. Depending on your situation, performance, performance-per-watt, and/or performance-per-dollar are what matters.
The current Intel pricing draws the first line. If performance-per-dollar matters to you, AMD's EPYC pricing is very competitive for a wide range of software applications. With the exception of database software and vectorizable HPC code, AMD's EPYC 7601 ($4200) offers slightly less or slightly better performance than Intel's Xeon 8176 ($8000+). However the real competitor is probably the Xeon 8160, which has 4 (-14%) fewer cores and slightly lower turbo clocks (-100 or -200 MHz). We expect that this CPU will likely offer 15% lower performance, and yet it still costs about $500 more ($4700) than the best EPYC. Of course, everything will depend on the final server system price, but it looks like AMD's new EPYC will put some serious performance-per-dollar pressure on the Intel line.
The Intel chip is indeed able to scale up in 8 sockets systems, but frankly that market is shrinking fast, and dual socket buyers could not care less.
Meanwhile, although we have yet to test it, AMD's single socket offering looks even more attractive. We estimate that a single EPYC 7551P would indeed outperform many of the dual Silver Xeon solutions. Overall the single-socket EPYC gives you about 8 cores more at similar clockspeeds than the 2P Intel, and AMD doesn't require explicit cross socket communication - the server board gets simpler and thus cheaper. For price conscious server buyers, this is an excellent option.
However, if your software is expensive, everything changes. In that case, you care less about the heavy price tags of the Platinum Xeons. For those scenarios, Intel's Skylake-EP Xeons deliver the highest single threaded performance (courtesy of the 3.8 GHz turbo clock), high throughput without much (hardware) tuning, and server managers get the reassurance of Intel's reliable track record. And if you use expensive HPC software, you will probably get the benefits of Intel's beefy AVX 2.0 and/or AVX-512 implementations.
AMD's flagship Epyc CPU has 32 cores, while the largest Skylake-EP Xeon CPU has 28 cores.
Quoted text is from page 23, "Closing Thoughts".
Previously: Google Gets its Hands on Skylake-Based Intel Xeons [soylentnews.org]
Intel Announces 4 to 18-Core Skylake-X CPUs [soylentnews.org]
AMD Epyc 7000-Series Launched With Up to 32 Cores [soylentnews.org]
Intel's Skylake and Kaby Lake CPUs Have Nasty Microcode Bug [soylentnews.org]
AVX-512: A "Hidden Gem"? [soylentnews.org]