Introduction, Design Features
On the one hand, 2017 has been a year of astonishing improvements in desktop PC processors, after years of ho-hum, mostly single-digit percentage gains from one chip generation to the next.
It started with AMD’s Ryzen 7 launch in March (see our review of the top-end AMD Ryzen 7 1800X), followed by midrange Ryzen 5 and lower-end Ryzen 3 chips. In most cases, they provided more cores and threads than Intel’s competing, similarly priced processors. But Intel didn’t let the summer slip by without a response, firing back with Core i9 chips (led by the Intel Core i9-7900X) on a new Core X-Series enthusiast-grade platform that included chips from both the “Skylake” (6th Generation) and “Kaby Lake” (7th Generation) chip generations.
But with all of these new chips and new levels of performance come some serious complexities that can be tough to keep up with—even for us lucky/cursed enough to do so for a living. AMD’s Ryzen chips, while they mostly win against equivalently priced Intel CPUs on multi-threaded tasks, introduce latency issues that result in lesser performance in 1080p gaming when paired with a high-end graphics card like the Nvidia GeForce GTX 1080 Founders Edition that we used for our testing.
The different CPUs on Intel’s Core X-Series platform, meanwhile, can enable (or disable) vastly different feature sets when dropped into the same motherboard. The Skylake-based Core X-Series chips, like the Core i9-7900X, deliver up to 44 lanes of PCI Express (PCIe) bandwidth, for rocking out with multiple graphics cards and high-speed solid-state storage. The Kaby Lake-based Core X-Series processors, like the Intel Core i7-7740X, provide just 16 lanes. The result of the lack of lanes, in short, means that if you drop one of the Kaby Lake Core X chips into an Intel X299 motherboard (X299 is the Core X-Series’ supporting chipset), several of the board’s slots and ports get switched off. And even if you don’t need those features, you’ll still be paying for them; most X299 motherboards sell for $250 and up.
Which brings us to the amusingly named Threadripper.
AMD is offering up its own response to Intel’s enthusiast Core X-Series chips, with the Ryzen Threadripper platform that we got a teaser of at a recent AMD event in Los Angeles, but which we’re looking at in detail here. Threadripper is quite impressive on paper and—as we’ll see later on in our Performance section—in many benchmarks and real-world tasks, too. The top-end Ryzen Threadripper 1950X that we’re looking at specifically in this review offers up a double-take-inducing 16 cores and 32 computing threads, while still being able to hit burst speeds of 4GHz, just like the fastest lower-end Ryzen 5 and Ryzen 7 parts. Oh, and the 32-thread 1950X is priced at $999, the same as Intel’s Core i9-7900X, which has “only” 10 cores and 20 threads.
Promotional Ryzen Threadripper chip, personalized by AMD for Computer Shopper
That sounds great (and it is), but know that the Threadripper platform and its accompanying X399 chipset have their own complex set of caveats and complications. For starters, the chip-install process is more complicated than any you’ve likely tried before, requiring its own install tool (included in the box with the chip). If you aren’t careful and scrupulous about following the directions, it’s easy to damage the new AMD TR4 motherboard processor socket and its bonkers-bountiful 4,094 pins. (That’s almost twice the 2,066 pins of Intel’s Core X-Series platform!) And that would almost certainly mean buying a new motherboard.
Also, at least for now, one clunky workaround tangles Threadripper, designed to mitigate some of the gaming-latency issues we saw with earlier AMD Ryzen chips. One is a Gaming Mode that you’ll have to enable (requiring a reboot) to get certain game titles to launch. It seems some games (including one that we use for testing, Far Cry Primal) choke in the very presence of a processor with 12 or more cores. You have to engage that mode, though; the Threadripper default is what AMD calls “Creator Mode,” which unleashes the full core-crunching power of the CPU. (More on that toward the end of this review.)
To be clear, though, these complications aren’t insurmountable. And if you’re a creative type who craves lots of cores for high-end media creation rather than gaming, you may be able to ignore some of them.
But to suss out how impressive AMD’s Ryzen Threadripper is (and the Threadripper 1950X in particular), we’re going to have to delve deep into the platform’s particulars before putting the chip through our usual spate of gaming and processor benchmarks. Follow us below while we do just that.
Threadripper: Meet the Platform
AMD’s Ryzen Threadripper chips are essentially consumer-aimed versions of the company’s recently launched Epyc chips for data centers and servers. The physical characteristics of the Epyc and Threadripper chips are either identical or nearly so. (We don’t have an Epyc chip on hand to say for sure.)
The underlying architecture of Threadripper, Epyc, and the mainstream Ryzen chips is the same “Zen” design found in the initial Ryzen 7 chips. Ryzen 7 houses one eight-core, 16-thread module, Threadripper connects two on one chip, and Epyc makes room for four. Additionally, Epyc includes a two-socket option, making possible systems with a kind-of-insane 128 threads in a single system. But the underlying silicon in the individual modules is essentially the same, whether we’re talking about mainstream Ryzen chips, Threadripper, or Epyc. This is, in some ways, similar to the lineage of Intel’s enthusiast chips, such as the new Core X-Series, which are effectively retooled versions of its Xeon server and enterprise processors.
But it’s fair to say that, in part because Epyc is itself brand-new (the company just launched Epyc in June 2017), the Threadripper chips and platform aren’t quite as refined as Intel’s competing offerings are. Intel has been churning out high-end desktop (HEDT) chips on the regular for years now. (See, for instance, our review of the Intel Core i7-3960X Extreme Edition…from 2011.)
AMD has been long out of this league of enthusiast-class CPUs, and it shows in some obvious and not-so-obvious ways. For starters, the Threadripper chips are positively huge by CPU standards, at about 3.75 inches on the diagonal (or roughly 3 inches long by 2.25 inches across). Not that physical chip size really matters in a desktop PC, but Intel’s competing Core X-Series chips measure about 2 inches by 1.75 inches, and the Ryzen chips are even smaller. Here’s a look at Threadripper surrounded by an ordinary Ryzen (to the left) and a Core X-Series (in the box at right).
It’s also fairly obvious that Threadripper chips are the result of effectively bolting a pair of Ryzen modules together at a silicon level. The Threadripper package even has two separate sets of contacts and components on the bottom, with a visible line running between them. Not that this is a major issue, but it’s tough to ignore in a brand-new platform when Intel’s competing chips are far smaller and aren’t as obviously separate modules paired together.
One of Threadripper’s larger quirks is also down to physicality, of a different sort: its complex installation process. And on the plus side (albeit superficially), the retail packaging is unusually interesting. But before we jump to that, let’s talk about the three Ryzen Threadripper processors that AMD has announced so far.
AMD Ryzen 7 1800X, in which we delved into it in some detail.
Aside from the top-end chip, AMD is also releasing a 12-core, $799 Ryzen Threadripper 1920X, which we’re also working on reviewing. (We tested it alongside the 1950X, and numbers for it will appear later in this review.) It has a base clock of 3.5GHz and tops out at the same 4GHz. Here’s a detailed look at the specs of the the two chips that are available today, direct from AMD…
The company also has an eight-core “entry-level” Ryzen Threadripper 1900X that will list for $549, with a high 3.8GHz base clock and the same 4GHz top clock as the other two chips. It won’t land, though, until a couple weeks after the initial pair of chips. The 1900X has been promised at the end of August 2017.
A couple of things are impressive here from the specs alone. First, AMD is able to keep its base and boost clock speeds quite high, even on the chips with the highest core counts. Compare this with the upcoming 18-core Intel Core i9-7980XE, which has a low 2.6GHz base clock, and a top Turbo clock speed that, at 4.2GHz, is higher than AMD’s 4GHz, but lower than the mainstream Core i7-7700K, which can ramp as high as 4.5GHz without overclocking.
One other thing of possible concern is cooling. The 180-watt TDP (thermal design power, a measurement of required heat dissipation) is quite high, higher even than the 165-watt TDP of Intel’s promised 18-core Core i9 chip. And, as we’ll see later in testing, it wasn’t easy for even a 360mm liquid cooler to keep the Threadripper 1950X cool, especially when overclocking. It may be worth waiting for new coolers that do a better job of covering a larger portion of the CPU’s heat spreader. Several existing liquid coolers have been cleared by AMD to work with these chips. But as this is physically by far the largest consumer processor in the last several years, existing coolers cover only the central portion of the chip. (More on this later.)
Threadripper Motherboards the X399 Chipset
The other stand-out feature of Threadripper involves motherboards and the new X399 chipset, which supports the new processor line. AMD hasn’t discussed X399 in great detail, but both the the diagram provided in its press materials (shown below) and our personal experience with the Asus X399 Republic of Gamers Zenith Extreme motherboard we used for testing indicate the platform is modern and feature-packed—and expensive.
Aside from support for key things like USB 3.1 Gen 2 and PCI Express/NVMe storage, every Threadripper processor ships with 64 lanes of PCI Express enabled. So even if you opt for the $549 1900X, you can still install lots of graphics cards and fast storage. This is what AMD means above by “no dark lanes” and sits in contrast to Intel’s Core X-Series platform, where lower-end chips like the Core i7-7740X have just 16 lanes (compared to 44 lanes on the high-end Core i9 chips). As noted earlier, with Intel’s X299 motherboards, depending on which chip you drop in, some ports and slots will be disabled (even though you have to pay for them when buying a board).
AMD simplifies this, in the process adding value for its lower-end Threadripper 1900X (and whatever other Threadripper CPUs that might or might not follow). All the ports and slots should work with an X399 motherboard, no matter what chip you install. But, with Threadripper there’s a hard limit of seven PCI Express devices, due to limitations involving onboard clock generators; each PCIe device needs one to function, and typical X399 boards will supply seven. So don’t expect to install an uber-fast, uber-pricey 10-drive PCIe RAID array like you technically can with Intel’s Core X-Series platform (via a feature called VROC). Then again, while Threadripper is undeniably a high-end platform, the amount of people who can afford to put together a setup like that is undoubtedly slim.
We certainly like the fact that AMD provides 64 PCIe lanes with all of its Threadripper chips. It should make the upcoming Threadripper 1900X far more appealing as a lower-cost entry point to AMD’s enthusiast platform than, say, the Intel entry-level Core X-Series like the Kaby Lake X are. The Core i5-7640X offers just 16 PCIe lanes, though it admittedly costs half as much as the Threadripper 1900X will. But honestly, with Nvidia’s current-generation graphics cards limited to just a pair in SLI, and current speedy storage drives eating up just four lanes, it’s tough to see how even the most well-heeled of enthusiasts would make any kind of practical use of all that PCIe bandwidth. Cryptocurrency miners and data scientists will likely appreciate it, but for gamers and enthusiasts, 64 lanes is arguably overkill. (Unless, maybe, you’re planning to drop four of AMD’s upcoming Radeon RX Vega cards into your new X399 build. Don’t let us stop you now.)
The other issue with X399 motherboards is cost. With the Ryzen 3/5/7 chips, board pricing has been another part of the value proposition, with X370, B350, and A320 boards generally coming in at either a lower price than Intel-based ones, or with more premium features (M.2 slots, LEDs, metal-wrapped PCIe x16 slots) than similarly priced Intel boards. But at least at this early stage, that’s not the case with Threadripper. When we wrote this in the days before the chips’ launch, there were just six X399 motherboards available for pre-order from Newegg, the same six we saw at a Threadripper briefing a couple of weeks before the launch. And they were all priced at $339 and up. Our Asus ROG Zenith Extreme was priced at $549. Motherboards on the competing Intel Core X-Series platform (using the Intel X299 chipset) start at about $100 less.
All that said, a couple of the X399 motherboards already have mail-in rebates, indicating pricing may fall soon after launch.
Ryzen Architecture Our Test-Bed PC
As for the architecture in Ryzen Threadripper, it’s essentially the same as what’s found in the Ryzen 3, 5, and 7 chips. There are just more modules here, providing more cores and threads. And the modules are connected via the same “Infinity Fabric” that AMD uses to connect the modules inside lesser Ryzen chips.
AMD does say, though, that it uses only “the very best” Ryzen dies for Threadripper chips. That likely, in part, accounts for the fact that all the Threadripper chips have high stock clock speeds. They are culled from the manufacturing process and set aside.
For more about the Ryzen architecture and features like XFR and Infinity Fabric, again, please see our review of the AMD Ryzen 7 1800X.
As for our test-bed, we built a Threadripper benchmarking PC based on an install kit that AMD supplied us. We’ve listed the parts below (along with some sources) and below that is a blow-by-blow video of the build process.
Beyond all that, though, we should take special care to illustrate the install process for the Threadripper chip itself, which is a wholly new experience. Let’s get into that on the next page.