AMD RYZES AGAIN
IT’S NOT QUITE ZEN 2, BUT AMD’S SECOND RYZEN INCARNATION STILL HAS A FEW ACES UP ITS SLEEVE. BENNETT RING TESTS THE NEW 2000-SERIES CPUS AND X470 MOTHERBOARDS.
It’s not quite Zen 2, but AMD’s second Ryzen incarnation still has a few aces up its sleeve.
It’s not an understatement to say that AMD smashed it out of the park with 2017’s release of the multi-headed Hydra that was the Ryzen CPU range. The company’s long-term strategy of releasing CPUs with ever-more cores finally paid off, releasing six- and eight-cored beasts at the same price as Intel’s quad-cored chips, dealing Intel a heavy blow when it came to applications that could make use of so many cores. Ryzen also added SMT, or Simultaneous Multithreading, a technology very similar to Intel’s HyperThreading, allowing each core to handle two threads at once. Add in a very healthy improvement when it came to Instructions Per Cycle (IPC) compared to its last chips, and we finally had a CPU war raging once again.
While Intel still retained a slight lead in applications that weren’t heavily threaded — which are currently still the norm, especially in games — AMD had a winner on its hands in multithreaded apps. And it did so at a stellar price point, around half of what Intel was charging for comparable multithreaded CPUs. Intel quickly lashed back with its 7th-generation Core CPU, doubling the number of cores while
maintaining a decent IPC lead over the Ryzen, but by then, the cat was out of the bag. AMD motherboards supporting the new Ryzen processors arrived in droves, even though AMD’s increase in CPU market share between 2016 and 2017 was only around 3%. However, that figure ignores the fact that people don’t upgrade their PCs every year, indicating a strong uptake in AMD CPU purchases. Not one to rest on its laurels, AMD is releasing the second iteration of the Zen architecture that powers the Ryzen CPUs, known as Zen+.
The two launch chips we’ll be covering this issue are the Ryzen 5 2600X and Ryzen 7 2700X. At first glance, they might seem to be an incremental improvement on the first Ryzen chips, yet there are some deeper changes that make these new chips worthy of your consideration if you’re yet to pull the Ryzen pin. Accompanying the second-generation Ryzen chips is also a new motherboard chipset in the form of the X470, which replaces last year’s X370.
BUILDING A BETTER BASE
Before we delve into the specifics of the new CPUs, let’s take a look at the new X470 chipset. Blessed be the engineers at AMD, as you don’t actually need to upgrade to the X470 to take advantage of Zen+ CPUs. They’ll quite happily play with last year’s X370based boards, just make sure it has the ‘Ryzen Desktop 2000 Ready’ moniker somewhere on its webpage or BIOS download site.
The X470 uses the same AM4 socket, a pin grid array layout AMD has been using for years. Yes, this means you’ll have to be extra careful about not bending any pins on the bottom of your new CPU, but it also means you don’t have to worry about bending pins inside the CPU socket, which can be even harder to straighten.
The easiest improvement to notice with the X470 is an apparent increase in the officially supported memory speed, from 2,666MHz to 2,999MHz. It’s a little vague, though, with some ‘ boards claiming it as the norm, while others saying it’s an overclocked speed. We also found the same memory speed glitch when testing these ‘ boards as the X370 — the twin 8GB G.Skill Sniper DDR4-3,444MHz memory modules that were supplied with our review kits usually defaulted to 2,133MHz when installed. To hit 2,999MHz required us to enter the BIOS to manually change the memory speed or switching to XMP mode. Having said that, once we’d done so, every ‘ board ran at 2,999MHz without a hitch.
The other major feature of the new X470 is what AMD is calling ‘StoreMI’ technology, a software solution that can even be purchased for X370 boards, for between US$20 and US$60, depending on how large you want your hybrid drive to be. It’s akin to Intel’s Optane technology, allowing your SSD to operate as a cache to your cranky old mechanical drive. Unfortunately, we didn’t have time to test this out, but have heard rumours that it’s compatible with Optane, which would be hilarious if true. AMD also claims that the X470 has a more refined power system, which should deliver better overclocking results, with many overclockers hitting 4.4GHz on all eight cores under load on the top of the line Ryzen 7 2700X (it usually operates at 3.7GHz when all eight cores are pushing data around). Other than that, though, this chipset seems to be business as usual, with the X470 being basically
“AMD had a winner on its hands in multi-threaded apps, and it did so at a stellar price point.”
identical to its predecessor. So then, on to the more interesting business — the Zen+ architecture itself.
THE BIGGEST IMPROVEMENT IS THE SMALLEST
All of the new Ryzen CPUs are built on the same Zen+ architecture, so we’re going to explain the basics for them before explaining how the four models differ. The biggest change to the Zen+ architecture is actually its smallest: that’s to say that it has undergone a manufacturing process shrink, down from 14nm on the original Zen to 12nm, thanks to the folks at GlobalFoundries. This is smaller than Intel’s existing 14nm+ process, and recent news suggests Intel won’t hit 10nm until 2019 — a rather large delay from the initial claims that it would hit 10nm in 2015. This means that the Zen+ can scale to faster frequencies without requiring extra juice or heat; in fact, the entire Zen+ range has seen a 50mV reduction in core voltage at the same time as increasing in speed. Helping to keep these chips even chillier is a refined Integrated Heat Spreader, which uses a new indium alloy and die metallisation to deliver temperatures up to 10ºC cooler than the first-generation Zen.
AMD has also paid attention to the Zen+’s IPC performance, although it’s still lagging behind Intel in this regard.
It does so through four enhancements, and cache performance is especially enhanced. According to AMD’s specs, L1 cache latency has dropped by 13%, L2 by 34%, L3 by 16% and DRAM latency by 11%. There’s even more meticulous power monitoring and delivery throughout the chip thanks to its ‘Precision Boost 2’ improvements with the result that, in ideal instances, all 16 threads on the new Ryzen 7 2600X can operate at the same frequency an original Ryzen CPU could manage on just two. Overall, these improvements combine to give the Zen+ a 3% IPC improvement when compared to the Zen design at the same clock speed.
FOUR TO THE FLOOR
AMD is initially launching four new Zen+ based CPUs, and the table (left) handily demonstrates how they differ. The amount of cache has increased, as have the frequencies. However, there is a trade-off despite the power improvements, with the 2700X’s TDP increasing to 105W, up from the prior Ryzen 7’s 1800X TDP of 95W. The good news is that all of the new Ryzens now come bundled with an air-cooled heatsink, and they’re of a surprisingly high quality. We were very impressed at the volume levels of the Wraith Prism under heavy load, reaching just 44dB during the stressful conditions of Prime95’s Small FFT Torture test. In other words, you’re not going to hear even the hottest CPU once it’s inside a case.
TO UPGRADE OR NOT TO UPGRADE?
If you’re an existing owner of the first generation of Ryzen CPU, the incremental nature of the performance increase doesn’t justify splashing out on a new Ryzen. However, they do offer performance that is comparable to Intel’s CPUs at a more wallet-friendly cost when you consider they include cooling and an overall lower entry price. Unfortunately, our benchmarks don’t really illustrate this performance parity, as they tend to focus on singlethreaded performance (we sadly had to remove the HWBot benchmark due to ongoing issues with HPET timing and the Meltdown/Spectre fiasco). But we can confidently say that multi-threaded applications are rapidly becoming the norm, and its here that the new Ryzen shines.
If you’re looking for the ultimate gaming beast, Intel is still the go-to guy in the room, but for most users, AMD’s spiffy new Ryzen is a very compelling option indeed. Just remember that you’re also going to need to buy a dedicated graphics card as, unlike AMD’s APUs, the Ryzen CPU doesn’t include an integrated GPU.
AMD’s stellar-priced Ryzen 5 2600X delivers great performance.
Stepping up to a Ryzen 7 2700X gives you a smidge more encoding power.