It feels like it has been years since we’ve had an AMD CPU on hand for a review, because it has! The last part we saw was an APU back in 2014. Since those years ago, AMD has come out with a completely new architecture, moved to a 14 nm process, gotten rid of those “modules” we’ve grown accustomed to, and are boasting a self-proclaimed 52% IPC gain over their previous CPU. Desktop processors now range from four cores without SMT (Simultaneous Multi-Threading) all the way up to eight cores with SMT. All of the processors have a vastly reduced TDP with the highest SKU coming in at 95 W (just four watts higher than the i7-7700K). This is a huge improvement compared to the 220 W the top Vishera CPU pulled down and the 125 W of the FX-8350.
Today, specifically, we’ll be talking about the Ryzen 7 series, the flagship 1800X CPU in the lineup. IPC improvements are huge over Excavator, thread count is up (depending how you view modules the core count is up also), and I know all of us enthusiasts are excited to see the new challenger who has been looming. That said, enough from me, let’s get to the chip.
Specifications and Features
Looking at the specifications table below, the 1800X is, as was mentioned, an octo-core with SMT for a total of sixteen threads. This total core/thread count comes from the use of two CPU Complexes (CCX), more on those later. The base clock comes in at 3.6 GHz and will boost two cores (four threads) to 4.0 GHz. The inclusion of XFR (Xtended Frequency Range) technology allows another 100 MHz over both the base and boost clocks, when temperature allows. The CPU sports a brand new 14 nm FinFET process. TDP (Thermal Design Power) is down to 95 W, a mere 43% of the TDP from the FX-9590, and only 76% of the TDP of the FX-8350. The cooling medium between the die and IHS is solder, instead of thermal paste as Intel has used on their Mainstream CPUs.
Memory on this CPU/platform supports a total of 128 GB with the base specification of DDR4-2400 in a dual channel configuration. It does not support ECC memory.
Regarding PCI Express (PCIe) support, Ryzen offers a total of 24 lanes out of the CPU allowing good flexibility for multiple cards, PCIe based NVMe SSDs, and other PCIe based devices. Sixteen of the lanes are dedicated to graphics, four are dedicated to the native M.2 PCIe NVMe slot, and the last four connect to the chipset. Different chipsets will provide their own additional PCIe lanes for even more device connectivity.
Windows 10 is the officially supported platform for Ryzen. That said, there will be drivers available for use with Windows 7 and 8.1, but know there is no official support for these older operating systems.
|AMD Ryzen 7 1800X Specifications|
|# of Cores||8|
|# of Threads||16|
|Base Clock Speed||3.6 GHz|
|Boost Clock Speed||4.0 GHz|
|Instruction Set Extensions||SSE 4.1/4.2/4a, AVX2, SHA|
|Lithography||14 nm FinFET|
|Transistor Count||4.8 billion|
|Thermal Solution Spec||Soldered|
|L1 Cache||128 KB I-Cache (64 KB per CCX)|
128 KB D-Cache (64 KB per CCX)
|L2 Cache||4 MB (512 KB per core)|
|L3 Cache||16 MB (8 MB per CCX)|
|Max Memory Size||128 GB|
|# of Memory Channels||2|
|ECC Memory Support||No|
|PCI Express Revision||3.0|
|PCI Express Configurations||1×16+1×4+1×4, 2×8+1×4+1×4|
|Max # of PCI Express Lanes||24 Lanes|
The table below is a list of the Ryzen lineup. In it we see the Ryzen 7 1800X is the top with its eight core, sixteen thread, configuration followed by a myriad of other SKUs. Every CPU on this list is overclockable, assuming you buy a motherboard with a chipset capable of doing so. Only SKUs with an X on the end have the new XFR (eXtended Frequency Range) technology, note. According to AMD, the X SKU processors are binned and manufactured to be better overclockers.
What really catches my eye here is AMD being able to put out an eight core, sixteen thread, CPU with a TDP of 65 W. That’s absolutely unheard of. Everything in Intel’s Broadwell-E lineup (non-Xeon) with more than four cores and eight threads is built on a 140 W TDP base.
|AMD Ryzen CPU Model||Cores/|
|Base Clock||Boost Clock||L3 Cache||Cooler Included||XFR||TDP|
|Ryzen 7 1800X||8/16||3.6 GHz||4.0 GHz||16 MB||No||Yes||95W-SR3+|
|Ryzen 7 1700X||8/16||3.4 GHz||3.8 GHz||16 MB||No||Yes||95W-SR3+|
|Ryzen 7 1700||8/16||3.0 GHz||3.7 GHz||16 MB||Wraith Spire||No||65W|
|Ryzen 5 1600X||6/12||3.6 GHz||4.0 GHz||Wraith Spire||Yes||95W|
|Ryzen 5 1500X||4/8||3.5 GHz||3.7 GHz||Wraith Spire||Yes||65W|
CPU Clock Speed Breakdown
To make it absolutely clear what the clock speed is in all loading/temperature scenarios, please see the table below.
|AMD Ryzen 7 1800X||High Temp Speed|
|Low Temp Speed|
|All Cores Loaded||3.6 GHz||3.7 GHz|
|Two Cores (Four Threads) Loaded||4.0 GHz||4.1 GHz|
|One Core (Two Threads) Loaded||4.0 GHz||4.1 GHz|
52% increase in IPC
Worldwide on shelf availability and competitive pricing
The launch models include three different 8-core samples; 1700, 1700X, and 1800X. These models come in at an MSRP of $329, $399, and $499 respectively and will be available worldwide on 3/2/2017.
AMD SenseMI Technology
First and foremost, it is important to understand that each AMD Ryzen processor has a distributed “smart grid” of interconnected sensors that are accurate to 1 mA, 1 mV, 1 mW, and 1°C with a polling rate of 1000/sec. These sensors generate vital telemetry data that feed into the Infinity Fabric control loop, and the control loop is empowered to make real time adjustments to AMD Ryzen processor’s behavior based on current and expected future operating conditions.
AMD SenseMI is a package of five related “senses” that rely on sophisticated learning algorithms and/or the command-and-control functionality of the Infinity Fabric to empower AMD Ryzen processors with Machine Intelligence (MI). This intelligence is used to fine-tune the performance and power characteristics of the cores, manage speculative cache fetches, and perform AI-based branch prediction.
- Pure Power
The distributed network of smart sensors that drive Precision Boost can do double duty to streamline processor power consumption with any given workload. And for next-level brilliance: telemetry data from the Pure Power optimization loop allows each AMD Ryzen processor to inspect the unique characteristics of its own silicon to extract individualized power management.
- Precision Boost
Using current/temperature/load data from the Infinity Fabric, Precision Boost modulates an AMD Ryzen processor’s clockspeeds in exacting 25 MHz steps. The granular clockspeed control gives AMD Ryzen processors greater operational freedom to press core frequency closer to the ideal frequency target, and allows for finer dithering at that ideal target. Users should expect a clockspeed plot to be reminiscent of a GPU, rather than a square wave, and this behavior is instrumental in sustaining a consistently high clockspeed.
- XFR (eXtended Frequency Range)
Rewards users who build or buy AMD Ryzen process-based systems with great cooling. Available on select AMD Ryzen processor models with the -X suffix, XFR lifts the maximum Precision Boost frequency, beyond the ordinary limits, in the presence of premium system and processor cooling. This is achieved by reading and forecasting AMD Ryzen processor’s distance to junction thermal limits, then converting available headroom into additional frequency.
- Neural Net Prediction
A true AI inside every AMD Ryzen processor harnesses a neural network to do real-time learning of an application’s behavior and speculate on its next moves. The predictive AI readies vital CPU instructions so the processor is always primed to tackle a new workload.
- Smart Prefetch
Sophisticated learning algorithms understand the internal patterns and behaviors of applications and anticipate what data will be needed for fast execution in the future. Smart Prefetch predicatively pre-loads that data into large caches on the AMD Ryzen processor to enable fast and responsive computing.
SMT (Simultaneous Multi-Threading)
This is AMD’s new equivalent to Intel’s HyperThreading (HT) technology. It allows each core to function as two threads, adding performance in multi-threaded applications.
Every Processor is Unlocked
AMD is allowing overclocking on all CPU models, much as they have in the past. The only caveat this time around is you must have a motherboard with a chipset supporting overclocking (X370, B350, or X300).
The “Zen” X86 Microarchitecture
On the performance side, the Zen micro-architecture represents a quantum leap in core execution capability versus AMD’s previous desktop designs. Notably, the Zen architecture features a 1.75x larger instruction scheduler window and 1.5x greater issue width and resources; this change allows “Zen” to schedule and send more work into the execution units. Further, a micro-op cache allows “Zen” to bypass L2 and L3 cache when utilizing frequently-accessed micro operations. Zen also gains a neural network-based branch prediction unit which allows the “Zen” architecture to be more intelligent about preparing optimal instructions and pathways for future work. Finally, products based on the “Zen” architecture may optionally utilize SMT to increase utilization of the compute pipeline by filling app-created pipeline bubbles with meaningful work.
A high-performance engine requires fuel, and the Zen architecture’s throughput characteristics deliver in this regard. Chief amongst the changes are major revisions to cache hierarchy with dedicated 64 KB L1 instruction and data caches, 512KB dedicated L2 cache per core, and 8 MB of L3 cache shared across four cores. This cache is augmented with a sophisticated learning prefetcher that speculatively harvests application data into the caches so they are available for immediate execution. Altogether, these changes establish lower level cache nearer to the core netting up to 5x greater cache bandwidth into a core.
Beyond adopting the more power efficient 14 nm FinFET process, the Zen architecture specifically utilizes the density-optimized version of the Global Foundries 14 nm FinFET process. This permits for smaller die sizes and lower operating voltages across the complete power/performance curve. The Zen architecture also incorporates AMD’s latest low power design methodologies, such as: the previously mentioned micro-op cache to reduce power-intensive faraway fetches, aggressive clock gating to zero out dynamic power consumption in minimally utilized regions of the core, and a stack engine for low-power address generation into the dispatcher.
It is in this realm, especially, that the power management wisdom of AMD’s APU teams shine through to impart in “Zen” the ability to scale from low-wattage mobile to HEDT configurations.
Scalability in the “Zen” architecture starts with the CPU Complex (CCX), a natively four core eight thread module. Each CCX has 64 KB L1 I-Cache, 64 KB L1 D-Cache, 512 KB dedicated L2 cache per core, and 8 MB L3 cache shared across cores. Each core within the CCX may optionally feature SMT for additional multi-threaded capabilities.
More than one CCX can be present in a “Zen”-based product, wherein the AMD Ryzen processor features two CCXes consisting of eight cores and 16 threads (total). Individual cores within the CCX may be disabled by AMD, and the CCXes communicate across the high-speed Infinity Fabric. This modular design allows AMD to scale core, thread, and cache quantities as necessary to target the full spectrum of the client, server, and HPC markets.
- Infinity Fabric
The Infinity Fabric, meanwhile, is a flexible and coherent interface/bus that allows AMD to quickly and efficiently integrate a sophisticated IP portfolio into a cohesive die. These assembled pieces can utilize the Infinity Fabric to exchange data between CCXes, system memory, and other controllers (e.g. memory, I/O, PCIe) present on the AMD Ryzen SoC design. The Infinity Fabric also gives “Zen” architecture powerful command and control capabilities, establishing a sensitive feedback loop that allows for real-time estimations and adjustments to core voltage, temperature, socket power draw, clockspeed, and more. This command and control functionality is instrumental to AMD SenseMI technology.
Here’s a screenshot showing all the different chipsets available for the AM4 platform, with their various levels of device support. As mentioned earlier, there are x4 PCIe lanes from the CPU dedicated to the chipset. These lanes are used as shown below, for each different chipset. On the X300 and A/B300 chipsets, the x4 PCIe lanes dedicated to the chipset are free for use by motherboard manufacturers. If you’re planning to overclock, please be sure the motherboard you choose has either the X370, B350, or X300 chipset.
Built in to the AMD Ryzen CPU is quite a bit of functionality, due to the SOC design. These features are available regardless of what chipset is in use.
Below is a picture of the new Ryzen 7 circuit map, this is immediately, vastly different from anything in the FX lineup. You can clearly see the two CCXes in use here, as well as each of the four cores in each CCX.
Here’s a picture of the FX-8350 CPU map for comparison. Notice how it has four distinct modules, which acted as two cores, instead of eight dedicated cores?
A Note on X300
The X300 is a one-of-a-kind in the PC industry, as it has been purpose-built by AMD to cultivate ITX solutions for the AMD Ryzen family of processors. X300 accomplishes this by enabling the SOC characteristics of the AMD Ryzen processor, which provides sufficient integrated I/O to fully enable the backplane and connectivity options of a premium ITX motherboard. Correspondingly, the X300 has no I/O functionality of its own, and exists instead to enable the remaining functionality of a chipset: secure boot, trusted platform module (TPM), and other security-related functionality. These hardware security capabilities fit into a chip the size of the fingernail on a human pinky finger.
The diminutive size and non-I/O capabilities of the X300 chipset permit motherboard manufacturers to connect this unique chipset to the AMD Ryzen processor with a dedicated SPI link, rather than the PCIe x4 link required for I/O chipsets. This dedicated link opens an additional four PCI Express Gen 3 lanes within the AMD Ryzen processor for general use, including additional NVMe devices, GigE, WLAN, or other quality-of-life companion cards and controllers common to the ITX form factor.
Due to the simplicity of the X300 chipset, it has an incredibly low power draw of only 1 W. This further assists motherboard manufacturers in designing ITX motherboards for the AMD Ryzen family of processors.
Below are some images from AMD of the product packaging for the new Ryzen CPUs. Some SKUs include a heatsink. Which model of heatsink depends on which CPU you’re looking at.
Next up are pictures of the 1800X sample we have. There are also pictures of it next to an AM3-based Athlon II 240 processor. Quite a bit of differences between AMD’s previous AM3 package and current AM4 package, once you get to the back. From the front they’re almost identical. You can see there are many more pins (courtesy of being an SOC) on the back side of the CPU, this is why the heatsink mounting footprint changed for AM4.
The data we have gathered will give us a great idea of its performance both at stock (no turbo), and matching clockspeeds to see IPC performance differences between them all. I have included Kaby Lake results with the i7-7700K, the hex core HyperThreaded Haswell-E i7-5820K, an eight core sixteen thread Haswell-E i7-5960X, and the top SKU Broadwell-E i7-6950X.
|Motherboard||GIGABYTE Z270X-Gaming 8||ASRock X99 OC Formula||GIGABYTE X99 SOC Champion||MSI X99A Gaming Pro Carbon|
|Memory||Corsair Vengeance LPX 2×8 GB DDR4-3000 15-17-17-35||Kingston Hyper X 4×4 GB DDR4-3000 MHz 15-15-15-35||G.SKILL Ripjaws4 4×4 GB DDR4-3000 15-15-15-35||G.SKILL Trident Z 4×8 GB DDR4-3200 14-16-16-35|
|HDD||OCZ Trion 150 480 GB||Samsung 950 Pro 512 GB||Samsung 850 EVO mSATA 250 GB||OCZ Trion 150 480 GB|
|Power Supply||EVGA SuperNova G2 850 W||EVGA SuperNova G2 750 W||Superflower Leadex 1 kW||Seasonic Platinum-1000|
|Video Card||EVGA GTX 980 Ti FTW GAMING||GIGABYTE GTX 980 Ti Xtreme Gaming||EVGA GTX 980 Ti Classified||GIGABYTE GTX 980 Ti Xtreme Gaming|
|Cooling||CoolerMaster Glacer 240L||Custom Loop with EK LTX CPU Block and 5.120 Radiator||Hyper 212 Evo||Custom Loop with EK LTX CPU Block and 5.120 Radiator|
|OS||Windows 10 x64||Windows 10 x64||Windows 10 x64||Windows 10 x64|
And the test system:
|CPU||AMD Ryzen 7 1800X|
|CPU Cooler||Noctua NH-U12S|
|Motherboard||GIGABYTE AX370-GAMING 5|
|RAM||Corsair Vengeance LPX 2×8 GB DDR4-3000 15-17-17-35|
|Graphics Card||EVGA GTX 980 Ti FTW GAMING|
|Hard Drive||OCZ Trion 150 480 GB|
|Power Supply||EVGA SuperNova G2 850 W|
|Operating System||Windows 10 x64|
In the care package from AMD, we find parts from GIGABYTE, Corsair, and Noctua for the Ryzen review. The motherboard delivered was the GIGABYTE AX370-GAMING 5, currently their highest level AM4 product. As a solution for RAM, the package from Corsair includes two Vengeance LPX DIMMs, this 2×8 GB kit is rated for DDR4-3000 at 15-17-17-35. Fresh off the line with a new mounting solution for AM4 is the NH-U12S from Noctua as a cooling solution (links here and here to Noctua’s AM4 mounting kits). Be sure to check out the links above for details on those products and how they fared when we pushed on things a bit. We have some pictures below of the supplied hardware.
The AX370-GAMING 5. Below we see a black/white/grey color scheme motherboard with quite a lot of features. Note, I have the Noctua mounting solution on the motherboard already. Looking at the back of the GAMING 5 we see all the heatsinks are attached with screws. The first PCIe 3.0 x16 slot is fully soldered, the second is soldered at x8, and the third at x4. We can also see a ten phase (6+4), fully digital VRM, this should be plenty for all but the highest of overclocks. There are quite a few enthusiast level options here including, but not limited to, onboard power/reset buttons, diagnostic LEDs, and a debug display. You have eight PWM fan connectors here, two of which are rated to 24 W and six at 12 W.
Here’s a few closer up shots of the GAMING 5, before we move on to some testing. I’ll let the pictures speak for themselves, but know there is all the connectivity you could ever need on this board. There’s M.2, U.2, USB 3.0, USB 2.0, TPM, audio, and plenty more.
All benchmarks were run with the motherboard being set to optimized defaults (outside of some memory settings which had to be configured manually). When “stock” is mentioned along with the clockspeed, it does not reflect the boost clocks, only the base clocks. I tested this way as it seems motherboards are different in how they work out of the box. This takes out any differences in how AMD/Intel utilize their turbo features and how the motherboards handle turbo, so this is more of a “run what you brung” type of testing for stock speeds. Memory speeds were set at DDR4-3000 15-15-15-35 for all testing, regardless of the kit specifications. The only exception to this is the AMD system running at DDR4-2933 15-15-15-35, this is due to how the memory dividers are arranged.
After the testing, we then shifted to comparing the AMD and Intel systems all at the same clockspeeds (4 GHz). This testing will flesh out the difference in Instructions Per Clock (IPC) between the samples. This also applies to the gaming tests.
- AIDA64 Engineer CPU, FPU, and Memory Tests
- Cinebench R11.5 and R15
- x265 1080p Benchmark (HWBOT)
- SuperPi 1M/32M
- WPrime 32M/1024M
All CPU tests were run at their default settings unless otherwise noted.
All game tests were run at 1920×1080 and 2560×1440. Please see our testing procedures for details on in-game settings. Due to availability of some of the older CPU’s we will be using a 980Ti for testing the games.
- 3DMark Fire Strike Extreme
- Crysis 3
- Dirt: Rally
- Ashes of the Singularity
- Rise of the Tomb Raider
Before we get into these numbers and graphs, I noticed the results for AIDA64 were all over the map. We reached out to our contacts regarding the results and were informed they have not been able to procure a pre-release Ryzen sample. Because of this, I received warnings in some tests about the CPU not being supported. This caused some curious results which are not accurate. As such, we will not be including these results until a later date. I will add them and update the discussion thread for this review when they are available.
Real World Tests
Next we will move on to something a bit more tangible/productivity based with compression, rendering, and encoding benchmarks. Here we can see what the added cores can really do for anyone who will utilize them. You’re talking about a $499 CPU getting into the ballpark of, and even exceeding, the performance of Intel’s $1000+ CPUs.
|Cinebench R11.5/R15, POVRay, x265 (HWBot), 7Zip – Raw Data|
|1800X @ 3.6 GHz||18.03||1636||3365.57||41||39793|
|i7-7700K @ 4.2 GHz||10.07||918||1960.54||33.25||25772|
|i7 5820K @ 3.3 GHz||11.0||1012||2082.87||22.42||30617|
|i7 5960X @ 3.0 GHz||15.26||1410||2845.74||0||42473|
|i7 6950X @ 3.0 GHz||19.26||1791||3569.4||35.17||51276|
Moving on from all the multi-threaded goodness above, we get to some Pi and Prime number based tests. SuperPi and WPrime, specifically. Even though AMD, with the Ryzen 7 1800X, didn’t shine like above in the testing here, it definitely held its own. Definitely much better than anything we found with Vishera or Excavator.
|SuperPi and wPrime Benchmarks – Raw Data|
|CPU||SuperPi 1M||SuperPi 32M||wPrime 32M||wPrime 1024M|
|1800X @ 3.6 GHz||10.765||560.991||4.502||91.698|
|i7-7700K @ 4.2 GHz||8.796||463.495||5.201||153.589|
|i7 5820K @ 3.3 GHz||10.883||541.953||4.763||142.087|
|i7 5960X @ 3.0 GHz||10.359||536.894||3.525||103.647|
|i7 6950X @ 3.0 GHz||9.517||509.764||2.894||77.42|
Just a reminder, all tests from this point forward have all CPU’s running at 4GHz instead of their stock speeds.
As far as the games go, we tested both at 1080p and 1440p resolutions to see if we can see a difference between them. My bets are no, we won’t see a tangible difference in FPS. And that bet was correct, all four CPU’s compared below show effectively the same framerate on each game at each resolution tested. For the gamers out there, you definitely won’t be disappointed with the performance of Ryzen!
As for the synthetic benchmark, 3DMark Fire Strike Extreme, small differences in Overall and Graphics scores. For the Physics score, though, we see the 1800X clearing out the 7700K by almost eight thousand points and coming near to the 6950X.
A Note Regarding Core Count and Gaming
There has always been an argument of “well, you only need 4c8t at most to play any game” but the gaming segment is shifting. Please see the below statement from Brad Wardell, the CEO of Stardock Entertainment and Oxide Games.
Oxide games is incredibly excited with what we are seeing from the Ryzen CPU. Using our Nitrous game engine, we are working to scale our existing and future game title performance to take full advantage of Ryzen and its 8-core, 16-thread architecture, and the results thus far are impressive. These optimizations are not yet available for Ryzen benchmarking. However, expect updates soon to enhance the performance of games like Ashes of the Singularity on Ryzen CPUs, as well as our future game releases.
Creative Assembly, the developers of Total War, have also released a statement regarding Ryzen.
Creative Assembly is committed to reviewing and optimizing its games on the all-new Ryzen CPU. While current third-party testing doesn’t reflect this yet, our joint optimization program with AMD means that we are looking at options to deliver performance optimization updates in the future to provide better performance on Ryzen CPUs moving forward.
Head to Head Results
In our head to head results, we ran all of the systems at 4 GHz. This shows the differences in IPC and cores directly. Recall from earlier the issues with AIDA64, again those results will be added when available. Overall, we see good scaling when upping the CPU speed. I really think the prediction functionality of SenseMI is helping in these longer tests, specifically wPrime 1024M and HWBot x265, you can see they seem to be higher performance than other comparable benchmarks.
Direct IPC Comparison
Due to the differences in SMT and HT, I decided it was best to run everything with one thread only. Here we can truly see the IPC of Ryzen in comparison to Intel’s offerings. Honestly, this is impressive for a brand new, barely optimized CPU.
Here I was able to add a one-off result of an FX-9370 at 4.0 GHz, this shows just how incredibly far AMD has come with the Ryzen-based CPU.
SMT and HT Efficiency Comparison
After looking at the IPC graph above you must be thinking “how is AMD doing so well on multi-threaded tests if Intel still has the better IPC”? Well, here’s how. Their SMT technology is as efficient as, or more efficient than, Intel’s HT. We can see as much as a 16% difference in efficiency here over the 6950X, nicely done AMD!
I’ll go ahead and start this by saying my results were limited by the air cooler in use. Water cooling would have gotten me farther, no doubt.
With that said, I also replaced the RAM with my trusty 2×8 GB G.SKILL Trident Z DDR4-3866 18-19-19-39. Due to BIOS limitations, I could only run up to DDR4-3200 though. As such, I also set the timings to 15-15-15-35 (CPUz keeps showing CL as +1 over the BIOS). Then tweaking of the CPU started, but I didn’t get too much past the 4 GHz number used above. I was able to get the system to stabilize out at 4,025 MHz though, which is almost a 12% increase over the stock base clock.
Below is a screenshot including the following benchmarks while the heavier overclock is applied. These include Cinebench R15, SuperPi 1M, wPrime 32M, and HWBot x265.
To go further here, I also ran 3DMark Fire Strike Extreme again at these elevated settings. The gains, especially on the physics score, were quite impressive for the mild change in speed. It went from 20,287 above to 21,605 here!
Information from AMD Regarding Overclocking
As a general guideline: a CPU voltage of up to 1.35 V is acceptable for driving everyday overclocks of the AMD Ryzen processor. Core voltages up to 1.45 V are also sustainable, but our models suggest that processor longevity may be affected. Regardless of your voltage, make sure you’re using capable cooling to keep temperatures as low as possible.
While there are never guarantees with overclocking, the majority of users should find that an eight core, sixteen thread, AMD Ryzen processor will achieve 4.2 GHz at a core voltage of 1.45 V. Advanced and accomplished overclockers trying to push record frequencies may find more headroom by disabling cores and/or disabling SMT on motherboards that offer these options in the BIOS.
There is no “stock” voltage value for Ryzen, due to how it operates, to base your starting voltage when manually setting vCore. As such, it also does not have a voltage table which it references for Auto settings.
The overclocking software from AMD is dubbed “Ryzen Master”. We’ll be getting hands-on with it in our upcoming overclocking guide. Once available there will be a link to it here.
Power Consumption and Temperatures
In the graph below we tested power use of the system across several situations from idle, to Prime 95 Small FFT (with FMA3/AVX) to playing Crysis 3. The system, at stock, was pulling a maximum of 203 W for CPU only load conditions. The PSU in use is roughly 90% efficient at this load level, meaning the system itself was only pulling 182.7 W. Seems about right considering there are enough fans on my test bench to account for at least 50 W of this power draw (yay for high speed Deltas). When overclocking to a static 4 GHz we see power consumption during Prime95 Small FFT jump by 84 W at the wall. Also, idle power might look high here, but again recall the fans on this system. The highest stock power draw from the wall I read was 325 W while playing Crysis 3, note there was a 250 W TDP GPU involved here. Overclocking for Crysis 3 only added 21 W to the draw.
It really looks like AMD has solved their power draw issues from the FX series of processors, a very welcome sight indeed!
Temperatures were actually surprisingly well controlled with the air cooler, I saw no throttling at any point. The highest temperature when at stock was 71°C, and overclocked was 90°C. Both of these occurred during Prime95 Small FFT.
UPDATE 3/3/2017: We have it on good word (not direct from AMD, but someone closely associated) that the core/die max temperature is 95°C. This is when you will see throttling and/or thermal shutdown. Quite the welcome change from all the FX processors, which were throttling at about 62°C!
Information from AMD Regarding TDP and Power Draw
It is a common mistake to conflate thermal watts (TDP) and electrical watts (“power draw”). Accurate knowledge of what TDP is, and how to calculate it, is therefore vitally important when drawing conclusions about the electrothermal characteristics of a silicon device.
Thermal Design Power (TDP) is strictly the measurement of an ASIC’s thermal output, which defines the cooling solution necessary to achieve rated performance. The TDP formula is straightforward:
TDP (Watts) = (tCase°C – tAmbient°C)/(HSF ϴca)
- tCase°C : Maximum temperature for the die/heatspreader junction to achieve rated performance.
- tAmbient°C : Maximum temperature at the HSF fan inlet to achieve rated performance.
- HSF ϴca (°C/W) : The minimum °C per Watt rating of the heatsink to achieve rated performance.
Using the established TDP formula, we can compute for the 95 W AMD Ryzen 7 1800X:
(60-42)/0.189 = 95.23W TDP
- tCase°C : 60°C optimal temperature for the processor lid (or IHS, integrated heatsink)
- tAmbient°C : optimal temperature for the case at HSF inlet.
- HSF ϴca (°C/W) : 0.189 ϴca
- Note: 0.189 ϴca is the AMD specification for cooler thermal performance to achieve rated CPU performance. The AMD Wraith Max corresponds with this specification, and many 3rd-party cooling solutions often exceed this requirement by a significant margin.
If the smart algorithms governing Precision Boost and XFR detect thermal conditions beneath these values (“headroom”), the AMD Ryzen processor will aggressively convert such headroom into meaningful performance for the user until a boundary condition is encountered.
In a heavily-multithreaded “all cores boost” scenario, this user-focused performance tuning permits the AMD Ryzen 7 1800X processor to ramp peak power draw up to the AMD Socket AM4 reference limit of 128 W. Thermal capacitance (“heat soak”) of the processor die, heatspreader, HSF, and junction solder allow the AMD Ryzen processor to amortize the tCase implications of peak power values over time, allowing the CPU to automatically increase performance while remaining inside the thermal boundaries defined by the TDP. Precision Boost and/or XFR will level off at 60 tCase°C or 128 W of electrical power (whichever comes first).
This insight into accurate TDP calculations also provides insight into how powerful aftermarket cooling solutions can provide additional performance opportunities for the AMD Ryzen processor. Lower operating temperatures provided by enthusiast cooling effectively reduce processor TDP, opening up additional thermal headroom for Precision Boost and XFR.
At launch we already see quite a few nice motherboards on the market, including the GIGABYTE AX370-GAMING 5 used here. Over 80 motherboards are available as of today for the AM4 platform, don’t forget these will also support the upcoming Ryzen-based APU’s! There are a lot of cooler manufacturers (15+ at the time of writing) who have mounting solutions for the AM4 platform already. For those who do not want to build their own system, there will be over 200 system integrators building Ryzen-based computers for their customers by the end of Q1 2017. Also coming up soon will be gaming towers from all the top-tier OEM’s (i.e. ASUS, Dell/Alienware, etc).
Of course, this review covered exclusively Ryzen 7, as it is the current release. The little brother, Ryzen 5, will be coming around in Q2 2017. The APU’s (these will also all be unlocked) and mobile solutions will be out sometime within 2017. No further information has been announced for these. Naples (server/workstation) equipment will be launching within Q2 of 2017 as well.
No matter how you slice this one, AMD has come out with a winner here. There are huge IPC gains, massive strides in the SOC platform, and a whole slew of new features to make the CPU faster whenever possible. Not only is power draw down, it is much more manageable than with FX. All of this at pricing that is not only competitive, it is downright disruptive in comparison to Intel’s pricing. We see a processor which comes in at an MSRP of $499 trading blows with two processors with MSRPs well in excess of $1000. Overclockers Approved!