Ryzen Release Thread

[SteelCrysis]

https://www.techpowerup.com/review/amd-r...00k/9.html

The Ryzen 9 3900X remains the fastest processor in our bench even with SMT disabled, beating the Core i9-9900K across multi-threaded tests. It also beats an untouched Ryzen 7 3700X. It's settled then that 12 physical cores beat 8-core/16-thread. However, the lack of SMT shaves a significant amount of performance off of the Ryzen 9 3900X. This goes to show that AMD's implementation of SMT is a sincere engineering feat and has a tangible performance gain. "Zen" simply wouldn't be the same without SMT, and AMD has been kind/smart enough to provide the feature on all its processor models priced north of $140 rather than keeping it exclusive to those above $300.

That said, we notice another fascinating phenomenon. With SMT disabled, the IPC of the "Zen 2" core seems to go up by roughly 2 percent. This directly impacts performance of software not in need of too many cores, namely games. We theorize that this could be due to two distinct things happening with the processor. For one, with the SMT off its shoulders, power-management of the processor is left to spread its power budget and Precision Boost headroom across fewer logical processors, so each of the cores runs at higher boost frequencies, positively impacting per-core performance. Secondly, to a smaller extent, performance is also benefited by the on-core schedulers not having to juggle resources between two logical processors. We saw hints of this when testing the Core i7-9700K, an 8-core processor that lacks SMT, and comparing it to the 8-core/16-thread i9-9900K. Despite slightly lower clock speeds, the i7-9700K managed to match or slightly exceed the i9-9900K at gaming. There are 12 such "unburdened" cores on a Ryzen 9 3900X, and hence, we see a neat 2% performance boost across gaming tests.
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We leave this review pleasantly surprised. As PC enthusiasts ourselves who game a lot, and whose productivity workload isn't too multi-threaded, we can see the benefit of leaving SMT off on a Ryzen 9 3900X. Gaming performance gets an uplift that's as high as 9 percent if you're really lucky, and the multi-threaded performance of the resulting processor is still higher than 8-core/16-thread processors. 12 physical cores still do carry a lot of weight around. When we do get the itch to benchmark or deal with workloads that can scale across any number of cores, getting a massive 31 percent performance boost is just a flick of a switch away in Ryzen Master, pending reboot, of course.