AMD Ryzen 7 2700X Review: Can AMD Cream Intel’s Coffee Lake?

It’s been just over a year since AMD launched its new Ryzen microprocessor based on the Zen architecture. Zen’s impact can scarcely be overstated; the CPU market has changed more in the past 16 months than in the previous six years combined. Today, AMD is launching its second generation of Ryzen microprocessors, and angling to regain the overall performance crown from Intel.

Before we dive into the review, let’s take a quick look at where things stand. The Ryzen 7 and Ryzen 5 families that AMD launched last year struck the heart of Intel’s desktop lineup. For years, Intel kept its product segmentation the same. Its Core i7 enthusiast desktop CPUs were quad-cores with Hyper-Threading (4C/8T), the Core i5 packed four cores and no Hyper-Threading (4C/4T), the entry-level enthusiast Core i3 was a dual-core with HT (2C/4T), and the low-end CPUs in the Pentium and Celeron families were dual cores without Hyper-Threading.

This status quo held for six years until Ryzen hit it like a bomb. Even before the family launched, Intel added Hyper-Threading support to its low-end processors. Once Ryzen was in-market, Intel slashed its 10-core CPU price in half. It introduced a new, short-lived set of Kaby Lake-X CPUs in an attempt to spur adoption of its High End DeskTop (HEDT) product lines. All of these efforts culminated with the launch of last year’s Core i7-8700K, an aggressively clocked six-core / 12-thread CPU on a new spin of Intel’s 14nm (14nm++). We put the Core i7-8700K up against the Ryzen 7 1800X last year and concluded that Intel’s potent mixture of clocks and IPC made the Core i7-8700K a superior choice to the Ryzen 7 1800X overall.

Since then, the top of the market has been quiet. Today, that changes. AMD intends to take back the overall performance crown, and it thinks the Ryzen 7 2700X is the CPU to do it.

Second Generation Ryzen, Not Ryzen 2
These new CPUs will almost inevitably be called Ryzen 2, but that’s not the nomenclature AMD uses. Ryzen 2 is reserved for an architectural refresh expected next year on GlobalFoundries’ 7nm process node. The CPU we’re reviewing today still uses the same fundamental architecture as the Ryzen CPUs we reviewed last year — with a few improvements. First, there’s a small amount of additional IPC gain, thanks to the cache and memory latency improvements detailed below. All slides can be enlarged by clicking on them.

ZenPlus-Uarch

The “up to” in the specs leave some wiggle room as to where the improvements are, but we’ll take a look at how the Ryzen 7 2700X compares with the 1800X in these metrics. Overall, a 3 percent IPC boost and better cache latencies are in line with what we expected to see 12 months after Ryzen’s initial debut.

The Ryzen 7 and Ryzen 5 2xxx CPUs pick up most of their improved performance from clock speed increases, not raw IPC improvements. At first glance, these clock speed gains are underwhelming; the Ryzen 7 2700X’s 3.7GHz base and 4.3GHz boost clock aren’t much different from the Ryzen 7 1800X’s 3.6GHz base and 4.1GHz boost. But AMD didn’t just nudge base and boost clocks upwards — it made several changes to the underlying algorithm and pushed TDP a nudge higher to give the CPUs more breathing room.

XFR2-3

In the past, AMD’s Precision Boost had a strict per-core demarcation. There was some light allowance for workloads, but frequencies only varied within a very narrow range based on XFR. The new Precision Boost 2 algorithm is designed to shift in a linear fashion, balancing core load, frequency, temperature, and voltage.

XFR2-2

In this diagram, the red line corresponds to the Ryzen 7 1800X’s actual Turbo frequencies, the yellow line are the clock speeds the Ryzen 7 2700X is expected to hold at a given thread count in OCCT, and the dotted white line represents an idealized linear curve. Unlike the Ryzen 7 1800X, which drops to 3.7GHz once the number of cores rises above two, the Ryzen 7 2700X maintains a higher turbo frequency, peaking just above 4GHz.

These higher sustained clocks are key to AMD’s claim that the Ryzen 7 2700X can deliver meaningful performance improvements compared with its predecessor. A 4GHz all-core boost frequency is a significant improvement on the 1800X’s 3.7GHz limitation. And speaking of frequency boosts, AMD’s Extended Frequency Range system has been tweaked as well.

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