AMD’s 16C/32T Ryzen Threadripper is likely the biggest processor in the consumer market.And that’s saying a lot, given the company’s rapid-fire releases addressing almost every facet of the desktop market. Now AMD is attacking Intel’s high-end desktop stronghold with up to 60% more cores, 36% more PCIe lanes, and 68% more cache than the comparably-priced Skylake-X models. AMD also doesn’t hack and slash at its product stack by calling I/O, so the company offers the same connectivity, even on its least-expensive models.
Impressively, all of the new Ryzen 7, 5, and 3 processors utilize the same underlying modular architecture. Threadripper is no exception, though it borrows some of AMD,s EPYC data center DNA to take the design to the next level.
Four years ago, Dr. Lisa Su, now AMD’s CEO, asked her team with building a server processor that could compete with Intel’s finest. That was an ambitious goal considering how far the company lagged behind its main competitor. AMD’s Zen core, which is a clean-sheet design that provides a 52% IPC boost over the company’s previous processors, was already underway and destined to power the new chips.
But processor design is a series of compromises. The company quickly learned that it couldn’t construct a single monolithic die able to deliver on its performance, memory, and I/O goals. Instead, AMD’s engineers put together modular four-core building blocks married in an eight-core die. And so, Zeppelin was born.
Now AMD uses the same Zeppelin building block in all of its processors. This approach is the epitome of maximizing limited resources; AMD can simply add more dies per package to create massively parallel chips, such as Threadripper and EPYC.
Though AMD faced significant headwinds at launch due to its unique Ryzen. AMD’s efforts are paying off, to Ryzen CPUs continue taking over our list of Best CPUs. Threadripper brings an entirely new set of challenges, but AMD has already designed in a few new features to help on the performance front.
Threadripper 1950X, 1920X & 1900X
It’s important to understand Threadripper’s intended audience. AMD geared the design for software developers, video/audio engineers, content creators, and heavy multitaskers. Though Threadripper isn’t aimed directly at gamers, particularly those who play at low resolutions with lightly-threaded titles, the company makes provisions for entertainment. The hefty core count should also boost gaming performance during intense streaming workloads, which we are currently testing for an upcoming feature.
The $1000 Ryzen Threadripper 1950X is the leader of AMD’s high-end desktop portfolio with 16C/32T, while the smaller 12C/24T 1920X and 8C/16T 1900X round out the family. Much like the rest of its Ryzen line-up, AMD’s Threadripper processors offer more cores than Intel at every price point. This time, however, we also get 64 PCIe 3.0 lanes (four of which are dedicated to the chipset) that outweigh Intel’s 44-lane flagship Core i9-7980XE.AMD includes all 64 lanes with each of its three Threadripper models, whereas Intel reduces connectivity for Skylake-X processors below $1000. Dual graphics cards are becoming more of a rarity in high-end gaming machines, but there are plenty of workloads still constrained by I/O. For instance, many taxing content creation workloads require hefty storage accommodations, and streamers often employ dedicated capture cards.
The Threadripper 1950X offers a 3.4 GHz base frequency that boosts to 3.6 GHz during heavily-threaded workloads. Mainstream Ryzen models feature a dual-core Precision Boost during lightly-threaded tasks, but due to Threadripper’s dual-die design (which we’ll cover on the following page), that expands to a quad-core 4.2 GHz boost. Much like Intel’s Skylake-X series, AMD offers unlocked multipliers for all Threadripper models but improves overclocking frequency and voltage scaling by selecting the top 5% of Zeppelin dies. That should equate to lower voltage requirements compared to Ryzen 7 models.
Each Zeppelin dies also sports 16MB of L3 cache, so the Threadripper 1950X wields a total of 32MB. That’s a lot more than the 24.75MB Intel enables on its upcoming 18C/36T Core i9-7980XE. Focusing in closer on the $1000 price range, the 1950X provides 18.25MB more L3 cache than Core i9-7900X. Of course, cache latency and bandwidth can be much more important than capacity, so we’ll have to measure each company’s balance between size and speed.
AMD’s dual-die architecture also comes with a 180W TDP rating, which is comparatively higher than Skylake-X’s 165W ceiling. Of course, TDP doesn’t map directly to power consumption during all workloads.
Of course, a large 180W TDP processor is going to require a beefy thermal solution, but there aren’t any water-coolers designed specifically for Threadripper’s massive heat spreader yet. To that end, AMD includes an Asetek bracket to provide compatibility with a wide range of existing closed-loop coolers. The current solution is an adequate stopgap until custom TR4 solutions arrive, but coverage isn’t optimal. There are also several air-cooling options available, including special Noctua TR4 designs with larger bases that cover the entire heat spreader surface.
Threadripper features independent dual-channel memory controllers, one per die, that combine to provide quad-channel support with varying data transfer rates (outlined below) based upon memory configurations. The platform supports ECC memory and a functional limit of 256GB of RAM, though it can support up to 2TB of capacity as memory density increases.
AMD connects the two Zeppelin die via its Infinity Fabric, so data resident in “remote” memory banks suffers higher latency. The company includes two new settings that help offset disadvantages inherent to the distributed memory architecture, which we’ll dive into on the next page. A Creator Mode offers the full heft of computing and memory resources for production workloads, while Game Mode tries to keep data resident in “local” memory and restricts processing to a single die. The idea of dedicated modes is certainly new to the desktop, and it requires a reboot after each change, but we found that it does offer tangible performance benefits in gaming workloads.
The X399 chipset also debuts with a new TR4 socket in tow, but it is an enthusiast-class platform that has roots in the data center. That means corresponding motherboards will carry a premium over AMD’s AM4 lineup, and may even rival the prices of Intel’s X299-equipped boards. Naturally, AMD has a solid roster of motherboard partners ready for its Threadripper launch, thus avoiding the maddening delay we experienced with the first Ryzen processors.