AMD's "7nm" Zen 2 8-core Ryzen 7 3700X and 12-core Ryzen 9 3900X CPUs have been reviewed:
The AMD 3rd Gen Ryzen Deep Dive Review: 3700X and 3900X Raising The Bar [anandtech.com]
From the conclusion page [anandtech.com]:
In the majority of controlled tests, AMD has done something they haven't been able to achieve in almost 15 years, since the tail-end of the Athlon 64's reign in 2005: that is to have a CPU microarchitecture with higher performance per clock than Intel's leading architecture. Zen 2 finally achieves this symbolic mark by a hair's margin, with the new core improving IPC by 10-13% when compared to Zen+.
Having said that, Intel still very much holds the single-threaded performance crown by a few percent. Intel's higher achieved frequencies as well as continued larger lead in memory sensitive workloads are still goals that AMD has to work towards to, and future Zen iterations will have to further improve in order to have a shot at the ST performance crown.
[...] In the majority of our system benchmarks, AMD more often than not is able to best Intel's Core i7-9700K and i9-9900K in terms of performance. It was particularly interesting to see the new 3rd gen Ryzens post larger improvements in the web tests, all thanks to Zen 2's improved and larger op cache.
In anything that is more than lightly multi-threaded, AMD is also able to take the performance crown among mainstream desktop processors, thanks to their inclusion of 12 cores in their top SKU Ryzen 3900X. For total MT throughput, Intel can still beat this with their massive X-series HEDT chips, but these server-derrived parts are in a completely different class in both features and price, and AMD has their own Threadripper parts to rival that. All of this means that for heavily threaded scenarios, the 3900X rules the roost among true desktop processors.
[...] Perhaps the best arguments for the 3700X and 3900X is their value as well as their power efficiency. At $329 the 3700X particularly seems exciting, and gamers will want to take note that it posts the same gaming performance as the $499 3900X. Considering that AMD is also shipping the CPU with the perfectly reasonable Wrath Spire cooler, this also adds on to the value that you get if you're budget conscious.
The 3900X essentially has no real competition when it comes to the multi-threaded performance that it's able to deliver. Here the chip not only bests Intel's mainstream desktop designs, but it's able to go toe-to-toe with the lowest rung of Intel's more specialized HEDT platforms. Even AMD's own Threadripper line-up is made irrelevant below 16 cores.
Also at Tom's Hardware [tomshardware.com], Guru3D [guru3d.com], and Wccftech [wccftech.com].
See also: AMD Zen 2 Microarchitecture Analysis: Ryzen 3000 and EPYC Rome [anandtech.com]
Previously: AMD and Intel at Computex 2019: First Ryzen 3000-Series CPUs and Navi GPU Announced [soylentnews.org]
AMD Details Three Navi GPUs and First Mainstream 16-Core CPU [soylentnews.org]