Intel Strikes Back
Although Intel added more cores to its previous-gen Coffee Lake processors in an effort to keep up with AMD’s Ryzen CPUs, struggles with its 10nm node obviously delayed a more significant response. The company’s ninth-generation Core processors, otherwise known as the Coffee Lake refresh, represent another step forward in a contentious battle for desktop supremacy.
Intel’s line-up matches AMD’s Ryzen core-for-core, including a new Core i9 with eight Hyper-Threaded cores (8C/16T) and the highest frequencies we’ve seen in the mainstream space. There’s also a bulked-up Core i7 armed with two extra cores, plus a revamped Core i5. AMD isn’t setting still though: The company recently released its own new flagship, the 16-core 32-thread Ryzen 9 3950X, to fend off Intel’s new challengers.
AMD’s high core counts, aggressive prices, and nods to enthusiasts have earned it plenty of goodwill. Now it’s Intel’s turn to respond. The Core i9-9900K, for instance, ships in a a translucent plastic dodecahedron obviously meant to wow system builders, similar to the way AMD impressed with its Threadripper packaging. Intel also switched back to using Solder Thermal Interface Material (STIM) between the die and heat spreader, facilitating better thermal transfer to cope with more cores and higher overclocks. Ninth-gen Core CPUs are also Intel’s first with hardware-based mitigations for the Meltdown and Foreshadow vulnerabilities. These should minimize the performance impact of circumventing recently discovered exploits.
Core i9-9900K is the fastest mainstream desktop processor we’ve ever tested. But it’s also one of the most expensive. Knowing that Intel does not match AMD’s value proposition, is the ultimate in desktop performance worth paying extra for? The new Core i9 was incredibly impressive through our benchmark suite. However, most users would be better served by cheaper alternatives, such as Core i7-9700K.
Then again, if money is no object and you have the need for speed, Core i9-9900K is the CPU to buy.
Intel Core i9-9900K
The Coffee Lake refresh begins with three new K-series processors. They all feature the same underlying Coffee Lake microarchitecture as previous-gen models. And as expected, the Core i5 and Core i7 brands are represented. This time around, though, an eight-core, 16-thread Core i9 commands the spotlight.
The new K-series chips are manufactured on Intel’s 14nm++ node, include an integrated UHD 630 graphics engine, sport unlocked ratio multipliers that enable easy overclocking, and boast support for dual-channel DDR4-2666 memory. Intel also responds to increasing RAM density by doubling memory capacity support up to 128GB.
|Core i9-9900K||Core i7-9700K||Core i5-9600K|
|Architecture||Coffee Lake||Coffee Lake||Coffee Lake|
|Cores / Threads||8 / 16||8 / 8||6 / 6|
|Base Frequency (GHz)||3.6||3.6||3.7|
|Boost Frequency ( Active Cores – GHz)||1-2 Cores – 5.04 Cores – 4.8 8 Cores – 4.7||1 Core – 4.92 Core 4.8 4 Core 4.78 Core 4.6||1 Core – 4.62 Core – 4.54 Core 4.46 Core 4.3|
|Integrated UHD Graphics GT2 (Base/Boost MHz)||350 / 1200||350 / 1200||350 / 1150|
|Recommended Customer Pricing||$488 – $499||$374 – $385||$262 – $263|
Core i9-9900K’s Solder TIM improves the thermal transfer efficiency between the die and heat spreader, facilitating the headroom needed for two more physical cores on the Core i9 and i7 models without violating a 95W envelope at base clock rates. What’s more, the -9900K’s base frequency is 3.6 GHz, just 100 MHz lower than the previous-gen Core i7-8700K. And that’s after adding those two extra cores.
The STIM, which is applied inside all three new models, also improves overclockability. Enthusiasts who previously lauded AMD for using Solder TIM in its Ryzen processors should be happy with Intel’s decision here.
|Base||1 Core||2 Cores||3 Cores||4 Cores||5 Cores||6 Cores||7 Cores||8 Cores|
|Core i9-9900K (GHz)||3.6||5.0||5.0||4.8||4.8||4.7||4.7||4.7||4.7|
|Core i7-9700K (GHz)||3.6||4.9||4.8||4.7||4.7||4.6||4.6||4.6||4.6|
|Core i7-8700K (GHz)||3.7||4.7||4.6||4.4||4.4||4.3||4.3||–||–|
|Core i7-8086K (GHz)||4.0||5.0||4.6||4.5||4.4||4.4||4.3||–||–|
|Core i5-9600K (GHz)||3.7||4.6||4.5||4.4||4.4||4.3||4.3||–||–|
|Core i5-8600K (GHz)||3.6||4.3||4.2||4.2||4.2||4.1||4.1||–||–|
Improved heat dissipation also facilitates impressive clock rates across the ninth-gen models. Core i9-9900K stretches up to 5.0 GHz when two cores are active, outstripping the Core i7-8086K and its ability to hit 5.0 GHz on one core. As you can see in the chart above, Intel is pushing the voltage/frequency curve with its eight-core models. They both feature much higher boost multipliers than previous-gen CPUs. These should help extend Intel’s advantage in lightly-threaded tasks like gaming. Meanwhile, the extra cores help Intel compete readily against Ryzen in more taxing workloads.
Core i7-7820X is perhaps the most comparable CPU from Intel’s high-end desktop portfolio. But it employs a fundamentally different design. The $600 chip requires an expensive X299 motherboard, is best paired to a quad-channel memory kit, lacks integrated graphics, and utilizes a mesh architecture for connecting on-die logic instead of the familiar ring bus (check out our deep dive for more information). As we’ve shown, the mesh architecture has a negative impact on some desktop-class workloads, so it isn’t the best solution for enthusiasts.
As expected, the -9900K’s extra cores are accompanied by two additional 2MB slices of L3 cache, adding up to 16MB across the processor. The Core i7-9700K comes with the same 12MB of L3 cache as its predecessor. Given a higher core count, though, this actually represents a lower cache-per-core ratio, meaning Intel purposely disabled some of the -9700K’s cache for the purpose of segmentation.
Intel’s Core i7 series traditionally features Hyper-Threading, allowing one physical core to execute two software threads simultaneously, thus boosting performance. Kaby Lake-based processors included up to four cores and eight threads, while Coffee Lake offered as many as six cores and 12 threads on the highest-end models. The 95W Core i7-9700K breaks this tradition with eight cores and no HT support. If you assume that HT yields a 15-20 percent performance uptick under ideal conditions, then Intel’s clever removal of the feature on its $374 Core i7-9700K should make the 8C/8T CPU faster than the 12-threaded Core i7-8700K in most workloads, maintaining the carefully manicured product stack.
Ninth-gen Core i5s still come with six cores and no Hyper-Threading, just like the Coffee Lake generation before them. The 95W Core i5-9600K ($265) operates at a 3.7 GHz base clock rate that boosts as high as 4.6 GHz. Intel pairs each core with a 1.5MB of L3 cache, adding up to 9MB.
|Model||Cores / Threads||Base Frequency||Boost Frequency||Memory Support||PCIe Lanes||Cache||TDP||Price|
|Core i9-9900K||8 / 16||3.6 GHz||5 GHz (1 / 2 Core)4.8 GHz (4 Core)4.7 GHz (6 / 8 Core)||DDR4-2666||16||16MB||95W||$488|
|Ryzen 7 2700X||8 / 16||3.7 GHz||4.3 GHz||DDR4-2966||16 + 4 (NVMe)||16MB||105W||$329|
|Core i7-9700K||8 / 8||3.6 GHz||4.9 GHz (1 Core)4.8 GHz (2 Core)4.7 GHz (4 Core)4.6 GHz (6 / 8 Core)||DDR4-2666||16||12MB||95W||$374|
|Core i7-8086K||6 / 12||4.0 GHz||5.0 GHz||DDR4-2666||16||12MB||95W||$425|
|Core i7-8700K||6 / 12||3.7 GHz||4.7 GHz||DDR4-2666||16||12MB||95W||$330|
|Ryzen 7 2700||8 / 16||3.2 GHz||4.1 GHz||DDR4-2966||16 + 4 (NVMe)||16MB||95W||$229|
|Core i5-9600K||6 / 6||3.7 GHz||4.6 GHz (1 Core)4.5 GHz (2 Core)4.4 GHz (4 Core)4.3 GHz (6 Core)||DDR4-2666||16||9MB||95W||$262|
|Core i5-8600K||6 / 6||3.6 GHz||4.3 GHz||DDR4-2966||16||9MB||95W||$279|
|Ryzen 5 2600X||6 / 12||3.6 GHz||4.2 GHz||DDR4-2966||16 + 4 (NVMe)||16MB||65W||$229|
|Ryzen 5 2600||6 / 12||3.4 GHz||3.9 GHz||DDR4-2966||16 + 4 (NVMe)||16MB||65W||$199|
The new Core CPUs drop into existing 300-series motherboards after a BIOS update, though Intel’s partners also have a slew of Z390 motherboards available, which you can see here. As we’ll illustrate, the Core i9-9900K, specifically, draws enough power to make VRM selection an important factor in your motherboard purchase, especially if you plan on overclocking. Luckily, most high-end Z390 motherboards already employ beefier power circuitry than the Z370 models.
Plan on buying a beefy cooler for the Core i9-9900K, too. Its eight-core die hides beneath the same heat spreader used on previous-gen six-core models, meaning that even with Solder TIM, thermal density presents challenges. Intel’s official spec sheet lists a 130W cooler as the entry-level solution. If you plan on tuning, open- or closed-loop liquid cooling is a must. Even then, thermal output could be what limits your overclock.
Hardware-Based Security Fixes, Architecture & Test Setup
Much like the Cascade and Whiskey Lake processors we recently covered, Intel’s Coffee Lake refresh comes with hardware-based mitigations for the Meltdown and L1TF (Foreshadow) vulnerabilities. Current Spectre and Meltdown mitigations, which Intel delivers via software and microcode patches, can reduce performance by up to 10% on newer CPUs, with older hardware suffering even larger losses. The new mitigations, baked directly into the silicon, should reduce or even eliminate the performance impact for a few vulnerabilities.
|Vulnerability||Coffee Lake Refresh/Whiskey Lake Mitigation||Cascade Lake Mitigation|
|Variant 1 (Spectre)||Operating System||Operating System/VMM|
|Variant 2 (Spectre)||Microcode + Operating System||In-Silicon + Operating System/VMM|
|Variant 3 (Meltdown)||In-Silicon||In-Silicon|
|Variant 3a||Microcode + Operating System||Firmware|
|Variant 4||Microcode + Operating System||Microcode + Operating System/VMM|
As we’re learning, it may take several processor generations before the fixes for all vulnerabilities are applied at a silicon level. Intel’s ninth-gen CPUs do still need a combination of microcode and operating system patches. But at least Meltdown and L1TF Foreshadow are patched fully in hardware.
Although we don’t have much new information about Coffee Lake refresh architectural changes, David Schoor at WikiChip says the new chips use a familiar ring bus, an internal high-speed pathway connecting the cores and cache.Image 1 of 3
This stands in contrast to the mesh architecture (deep dive here) that Intel uses on its high-end desktop models, including the eight-core Core i7-7820X. We’ve found that the mesh architecture has a negative impact on some desktop applications, including games, which Intel acknowledges. The mesh architecture was designed to increase scalability as it expands to higher core counts in the Xeon family.
Overclocking, Rounds One and Two
We tapped Corsair’s H115i v2 to test our Core i9-9900K sample in the U.S. lab. This liquid cooler afforded enough headroom to sustain a 5.0 GHz overclock with a 1.33V Vcore and a Load Line Calibration 4 setting. It kept the chip at a steady 85°C during extended non-AVX stress tests. Folding in AVX instructions did, unfortunately, overwhelm the all-in-one. To reign in the thermal output, we set the AVX offset to -2, meaning the chip ran at 4.8 GHz during AVX-optimized workloads and 5.0 GHz in the absence of AVX instructions. We maintained a temperature of 95°C during three hours of Prime95 using those settings.
To model real-world settings attainable by enthusiasts with closed-loop liquid coolers, we applied the -2 AVX offset for our 5.0 GHz overclock in the gaming, office and productivity, and rendering tests.
We did not use an offset for the workstation graphics, compute, power consumption, and temperatures sections.
MEG Z390 Godlike
We’re using MSI’s MEG Z390 Godlike as our test platform for all Intel processors. This pricey board retails for $600, but has the power delivery subsystem to support aggressive overclocking.
The MSI MEG Z390 Godlike sits at the top of MSI’s motherboard hierarchy. It has a decked-out 18-phase power delivery subsystem that’s designed to squeeze every drop of performance out of Intel’s new processors. It also comes with a few nifty accessories like an M.2 PCIe riser card and an HDMI streaming card.
|Test System & Configuration|
|Hardware||Germany Intel LGA 1151 (Z390)Intel Core i9-9900K, i7-9700K, i5-9600K, i7-8700K, i5-8600K, i5-8400MSI MEG Z390 Godlike2x 8GB G.Skill FlareX DDR4-3200 @ DDR4-2667 & DDR4-3466AMD Socket AM4 (400-Series)AMD Ryzen 7 and Ryzen 5 MSI X470 Gaming M7 AC 2x 8GB G.Skill FlareX DDR4-3200 @ DDR4-2667, DDR4-3466Intel LGA 2066 Intel Core i7 MSI X299 Gaming Pro Carbon AC 4x 8GB G.Skill FlareX DDR4-3200 @ DDR4-2666All SystemsGeForce GTX 1080 Founders Edition (Gaming) Nvidia Quadro P6000 (Workstation)1x 1TB Toshiba OCZ RD400 (M.2, System SSD) 4x 1TB Crucial MX300 (Storage, Images)be quiet! Dark Power Pro 11, 850W Windows 10 Pro (All Updates)U.S. Intel LGA 1151 (Z390)Intel Core i9-9900K, i7-9700K, i5-9600K, i7-8700K, i5-8600K, i5-8400MSI MEG Z390 Godlike2x 8GB G.Skill FlareX DDR4-3200 @ DDR4-2667 & DDR4-3466Intel LGA 2066Intel Core i9-7820XMSI X299 Gaming Pro Carbon AC4x 8GB G.Skill FlareX DDR4-3200 @ DDR4-2666, DDR4-3200AMD Socket AM4 (400-Series)AMD Ryzen 7 2700X, Ryzen 5 2600XMSI X470 Gaming M7 AC2x 8GB G.Skill FlareX DDR4-3200 @ DDR4-2933All SystemsEVGA GeForce GTX 1080 FE 1TB Samsung PM863SilverStone ST1500-TI, 1500WWindows 10 Pro (All Updates)|
|Cooling||GermanyAMD Wraith RipperAlphacool Ice Block XPXEnermax LiqTech 240 TR4Thermal Grizzly KryonautU.S.Wraith RipperCorsair H115iEnermax Liqtech 240 TR4 II|
|Power Consumption Measurement||Contact-free DC Measurement at PCIe Slot (Using a Riser Card) Contact-free DC Measurement at External Auxiliary Power Supply Cable Direct Voltage Measurement at Power Supply 2x Rohde & Schwarz HMO 3054, 500 MHz Digital Multi-Channel Oscilloscope with Storage Function4x Rohde & Schwarz HZO50 Current Probe (1mA – 30A, 100 kHz, DC) 4x Rohde & Schwarz HZ355 (10:1 Probes, 500 MHz) 1x Rohde & Schwarz HMC 8012 Digital Multimeter with Storage Function|
|Thermal Measurement||1x Optris PI640 80 Hz Infrared Camera + PI Connect Real-Time Infrared Monitoring and Recording|
|Acoustic Measurement||NTI Audio M2211 (with Calibration File, Low Cut at 50Hz) Steinberg UR12 (with Phantom Power for Microphones)Creative X7, Smaart v.7 Custom-Made Proprietary Measurement Chamber, 3.5 x 1.8 x 2.2m (L x D x H) Perpendicular to Center of Noise Source(s), Measurement Distance of 50cm Noise Level in dB(A) (Slow), Real-time Frequency Analyzer (RTA) Graphical Frequency Spectrum of Noise|
We aren’t big fans of using synthetic benchmarks to measure performance, but 3DMark’s DX11 and DX12 CPU tests provide useful insight into the amount of horsepower available to game engines.
The Core i9-9900K’s eight cores easily beat Ryzen 7 2700X during the DX12 and DX11 CPU benchmarks. For perspective, the Core i9-9900K has the same 4.7 GHz all-core boost frequency as the Core i7-8700K’s single-core boost, which is quite impressive. As expected, tuning Core i9-9900K propels it into a league of its own.
In the DX12 test, we see a nice step forward from Core i7-9700K compared to its predecessor, the Core i7-8700K. That improvement is despite a loss of Hyper-Threading technology on the new Core i7 model.
Architecturally, the Core i5-9600K is very similar to Core i5-8600K. They offer the same number of cores. But the newer chip’s higher clock rates deliver tangible gains.
UL’s VRMark test lets you gauge your system’s suitability for use with the HTC Vive or Oculus Rift, even if you don’t currently own an HMD. UL defines a passing score as anything above 109 FPS. The Core i7-9700K posts a surprisingly strong frame rate, beating the overclocked -9900K. That implies this benchmark runs best on eight physical cores.
Ashes of the Singularity: Escalation
Image 1 of 3
Ashes of the Singularity: Escalation is a computationally intense title that scales well with thread count. A stock Core i9-9900K beats the rest of the processors, except for an overclocked Core i7-8700K.