Introduction, Features Platform Details
AMD’s initial launch of its all-new “Zen” architecture and Ryzen chip platform—with its high-end Ryzen 7 chips—was a tad bumpy, though positive overall. The AMD Ryzen 7 1800XRyzen 1700XIntel Core i7-6900KCore i7-6950X Extreme Edition.
Pair one of these new chips with a comparatively low-cost motherboard (starting as low as $69, when we wrote this in mid-April 2017), and AMD’s Ryzen 7 can be quite the bargain for performance-hungry users on a budget. The major wrinkle, though, lies in 1080p gaming performance.
When we tested the Ryzen 7 chips at resolutions above 1080p when paired with an Nvidia GeForce GTX 1080 graphics card, performance was effectively identical to a PC with the same card and a high-end Intel CPU. But stepping down to 1080p (where the vast majority of us still game), the high-end Intel chips delivered much higher frame rates, tacking on an extra 20 to 40 frames per second (fps) compared to the Ryzen 7 chips. That’s a huge drop in gaming performance for the AMD CPUs, although the AMD chips were still able to deliver smooth performance, averaging well above 60fps in our testing at 1080p.
AMD promised gaming improvements, as driver updates and game patches arrived. And indeed, that seems to be happening, to a certain extent. A recent update to the game Ashes of the Singularity promises significant performance gains at 1080p, and a new AMD-specific power plan for Windows 10 (which we used in our benchmark testing) gives the chip hardware more control over how quickly it can ramp up and down, and when it parks CPU cores that aren’t currently being used. AMD says this should translate to better performance in Total War: Warhammer, Gears of War 4, Battlefield 4, and a few other games.
In the midst of these promising (though far from across-the-board) changes for the Ryzen platform, lands AMD’s midrange CPU lineup. It’s based on the same architecture as Ryzen 7.
These Ryzen 5 chips are more varied in their core count than the Ryzen 7 options (which are all eight cores and 16 threads). And there are more of them. AMD has four Ryzen 5 chips on offer, starting with the four-core, eight thread Ryzen 5 1400 and ramping up to the six-core, 12-thread Ryzen 5 1600X. Pricing is, as we’d expect, more modest for these midrange chips, as well, with the Ryzen 5 1400 selling for $169 and the Ryzen 5 1600X topping out the Ryzen 5 line at $249.
Today, we’re specifically looking at the chip one step up from the Ryzen 5 1400, the Ryzen 5 1500X. It’s also a four-core, eight-thread CPU, with a variable clock speed between 3.5GHz and 3.7GHz, and the ability go even higher if you pair it with a very capable cooler. (More on that later.) The Ryzen 5 1500X will sell for $189, which puts it right in the middle, in terms of price, between the Intel Core i3-7350KCore i5-6600K (a four-core, four-thread chip that sells for around $220).
So, then, how does the Ryzen 5 1500X stack up against Intel’s offerings, and has AMD made headway with the 1080p gaming-performance issues we first saw with the Ryzen 7 chips? To find that out, we’re going to have to dig deep, and of course put the chips through our suite of performance benchmarks. Follow us below as we do just that.
Chip Lineup Details: Ryzen 7, Ryzen 5 Ryzen 3
From a computing-performance perspective, AMD’s Ryzen 7 processors are quite impressive for CPUs priced between $329 and $499. But of course, not everyone can afford to spend that much on a processor—even if it’s arguably a steal compared to Intel’s pricing. And money aside, unless you are a content creator, transcode video constantly, or run CPU-intensive research tasks, you won’t often make use of the eight cores and 16 threads baked into the Ryzen 7 parts, anyway. For power users with lesser demands (and tighter budgets), AMD is offering up four Ryzen 5 processors, starting today, with fewer cores and lower prices.
The Ryzen 5 lineup consists of two six-core and two four-core Ryzen 5 chips. Lower-end Ryzen 3 offerings are coming, says AMD, in the second half of 2017.
A couple of features on all of these chips set them apart from Intel’s competing offerings. For one: AMD says all the Ryzen chips will be unlocked for overclocking. And, at least from the details we have about the Ryzen 7 and Ryzen 5 chips announced so far, all those chips will feature thread-doubling simultaneous multi-threading (SMT). SMT is similar to the Hyper-Threading technology featured in most (but not all) of Intel’s mid-to-high-end Core processors. Notably, the unlocked Intel Core i5-7600K and previous-generation Core i5-6600K lacks Hyper-Threading, leaving it stuck at four processing threads, while AMD’s Ryzen 5 1600 and 1600X chips will have 12 available processing threads, and the Ryzen 5 1500X we’re looking at here has eight.
AMD sent along a review sample of the top-end $249 Ryzen 5 1600X, along with the Ryzen 5 1500X, so you can expect a review of that higher-end chip soon after this one. In the meantime, we tested the two chips alongside each other, so you’ll be able to get a sense of how both perform when we get to our benchmarks later on.
AMD says the Ryzen 5 1500X has a 65-watt TDP (thermal design power, a measurement of heat dissipation requirements), which is significantly less than the 95-watt rating of the higher-end Ryzen 7 chips. The Ryzen 5 1500X has half the physical cores, so that’s not exactly surprising, though it will make this Ryzen 5 chip easier to cool in compact cases.
The Ryzen 5 1500X has a base clock speed of 3.5GHz, and the ability to ramp up to 3.7GHz. It can technically ramp up to 3.9GHz under certain conditions with a reasonably powerful cooler, thanks its XFR feature (more on XFR later on). AMD sent along this chip’s stock Wraith Spire cooler, which we used for most of our testing. Interestingly, it’s rated to 95 watts of cooling, but as we’ll see later in our benchmarks, if you want the best performance possible, particularly for overclocking, you will want to invest in something more powerful, like a self-contained liquid cooler or a larger air cooler. The Wraith Spire worked fine at stock speed tests, but it wasn’t much help getting above the stock clock settings.
Nvidia GeForce GTX 1080 Ti or one of AMD’s upcoming “Vega” cards? That will set you back as little as $69, say, for the ASRock AB350M-HDV. The higher-end X370 boards are better equipped to handle high-end builds, and support dual-card Nvidia configurations in SLI. But some B350 boards have two graphics-card slots and support dual-AMD-card setups via CrossFire.
That’s the case with the Gigabyte AB350-Gaming 3 that we used for testing. It sells for between $99 and $109, and it is no low-end, feature-barren board. It sports RGB lighting, metal-wrapped graphics-card slots, and an M.2 slot for super-fast solid-state drives like the Samsung SSD 960 EVO. You can certainly spend more; some initial AM4 boards are priced as high as $300. But we’ve seen several solid-looking options in the $100 range. You can certainly find good Intel-based options in this price range, as well. But if you care about features like RGB lighting and metal-wrapped slots (and we’re certainly not implying that everyone does), you’ll generally have to pay a little more for an Intel-based board with comparable features.
Technically, five new chipsets are on offer with AMD’s new motherboards. Here’s a look at their primary features and how they differ, in a summary direct from AMD.
As noted earlier, if you want to install multiple Nvidia graphics cards, you’ll need to opt for the top-end X370 chipset, but even those boards start just at around $150. The A320 chipset and the A300 don’t support overclocking, and the latter lacks native support for USB 3.1 Gen 2. But those boards, when they arrive, will likely be even more price-aggressive, because they’re a step down from the B350 boards, which start as low as $69.
These lower-end boards were just trickling out when we wrote this, so we’ll have wait to see where they land in terms of features and pricing. But we would not be surprised to see some of these boards priced as low as $50. Now, we’re not suggesting you opt for the lowest-price board you can find, but the idea of dropping a $189 eight-thread CPU into a sub-$100 motherboard and getting similar (and in some tests better) performance to what you’d get with a roughly $400 Intel CPU/motherboard combination is appealing.
How is AMD able to get its board partners to produce such comparatively inexpensive motherboards? Primarily, it’s because AMD’s Ryzen chips (and its upcoming “Raven Ridge” CPU/GPU chips, or APUs, which will use the same AM4 socket) integrate much of the electronics required for interfaces such as USB, SATA, and PCI Express into the chips themselves. As a result, far fewer electronics need to be built onto the boards themselves.
Not everything here works in AMD’s favor. These chipsets tend to have fewer PCI Express lanes and SATA ports than many enthusiast motherboard/CPU combos from Intel. The top-end AMD X370 chipset natively supports six SATA III ports and 16 lanes of PCI Express Gen 2 for speedy SSDs (on top of the 24 lanes of PCIe on the Ryzen chips themselves). Intel’s X99 platform, in contrast, supports 10 SATA III ports and up to 40 PCI Express lanes hanging off the CPU. (The junior Broadwell-E chip, the Core i7-6800K, has “just” 28 lanes.) So, for those planning on shoving piles of drives and other hardware inside their systems, Intel’s pricier platform will still hold plenty of appeal. But for the vast majority of users looking to drop in a CPU, one or two graphics cards, and a drive or three, AMD’s offering should more than suffice—usually at a lower price point than comparable Intel-based boards.
Another area of concern in the weeks after the initial Ryzen launch was motherboard availability. For several days, very few AM4 motherboards were in stock on Newegg and other online outlets, sometimes dwindling down to just a few in-stock options. That situation seemed to be improving as we wrote this in mid-April 2017. Then, Newegg showed 11 motherboards in stock, although five others were still listed as “Auto-Notify,” indicating Newegg wasn’t sure when those models would again be available. And even if all of those boards were in stock, 33 models is still a far cry from the “more than 80” motherboards AMD’s CEO and president, Lisa Hsu, promised would launch with Ryzen. There are still far more motherboard options available on the Intel side of the silicon fence.
The Architecture Basics
As noted earlier, the Ryzen chips represent an entirely new architecture for AMD. Gone are the paired modules of cores sharing an L2 cache that was a hallmark of the FX processor line. Ryzen’s cores are more independent, and they also introduce the thread-doubling SMT we mentioned earlier. SMT is similar to Intel’s Hyper-Threading, which allows demanding software that’s written to take advantage of it to tackle two computing threads on each core.
CPU-architecture details can get extremely technical as soon as you look any deeper than the the surface. But to give you a sense of how AMD has achieved its performance gains with its new Zen architecture, the company says it has incorporated an instruction-scheduler window that’s 1.75 times larger, with a 1.5 times greater issue width, that enables AMD to send more work to the chip’s execution units.
Here’s a look at the Ryzen die layout, again direct from AMD…
Also, a new branch-prediction unit, which the company calls “neural-network-based,” helps the chips be smarter about preparing and optimizing instructions and paths for tasks that the chip will need to tackle in the immediate future.
This all sounds good, to the extent that it can be parsed and appreciated without a computer engineering degree. But power efficiency is another area in which AMD’s FX chips have lagged behind Intel for years. The company’s FX-8370Core i7-6900K, and a big, big leap over the 32nm process used for AMD’s previous-generation FX chips. And AMD says this 14nm process has already been “density optimized” by the company’s manufacturing partner, Global Foundries.
Other efficiency-focused features include a “micro-op” cache that keeps important instructions and data close to the cores, rather than having to reach out to comparatively far-off L2 or L3 caches; and aggressive clock gating, so there’s less wasted power in areas of the cores that aren’t being used. Here’s a visual look at how AMD aims to keep power draw down.
Better Clocks With Better Coolers: XFR
You may have noticed that the entry-level Ryzen 5 chip, the Ryzen 5 1400, lacks an “X” at the end of its name, as does the Ryzen 5 1600, unlike the Ryzen 5 1500X and 1600X. This X indicates the inclusion of a feature AMD is calling Extended Frequency Range (XFR).
XFR makes use of what the company is calling “SenseMI,” sensors and algorithms that, among other things, measure voltage, power, and temperature in fine detail, a thousand times per second. The sensors monitor where the chip is situated within its power and heat envelopes, as well as where it expects to be in the near term.
When it comes to clock speeds, SenseMI allows the chip to “sense” when it has sufficient cooling and, assuming you have an XFR-enabled model (again: one of those CPUs that end in “X”), to clock even higher than the top boost-clock speed. The idea, at least in part, is to reward buyers or builders who invest in large air coolers or liquid cooling to enjoy some performance gains.
Now, that sure sounds good. But, at least with the first round of Ryzen 7 chips, the XFR boost is locked at just an extra 100MHz. That gets a bit better with the Ryzen 5 1500X; it’s able to jump up an extra 200MHz with XFR, taking it from a top 3.7GHz to 3.9GHz if there’s lots of cooling potential available.
We said when we reviewed the Ryzen 7 1800X that we hoped that future Ryzen chips would allow for a bigger XFR boost, because the above seems like a long way to go, both in terms of underlying technology and the extra cost of a better cooler, to gain just an extra 100MHz. That’s certainly improved here. But going out of your way for XFR with this chip only really makes sense if you already have an existing cooler that works with the new AM4 mounting mechanism. Many cooler manufacturers are offering adapter kits for a small price, or even free, though you’ll have to mail away for them.
But we don’t recommend buying a new, expensive cooler for the 1500X, because while you might get slightly better performance by doing so and placing it on this chip, that money would be better spent by stepping up to one of the higher-end Ryzen 5 chips. The Ryzen 5 1600 costs just $40 more, and it nets you two more physical cores and four more computing threads.
Two things to note about the Ryzen 7 chips as a whole: These are CPUs only, with no onboard graphics, in the same mold as Intel’s CPU-only E-Series chips. You’ll need to use them with a discrete video card. And the underside will look familiar to the AMD faithful…
The Ryzen chips still use pins on the CPU itself, not the socket-side pins and on-chip contacts that Intel has long since moved to.