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We have with us the Core i7-11700KF processor. When Intel debuted its 11th Gen Core “Rocket Lake” desktop processor lineup in March, much of the attention was grabbed by the Core i9-11900K and Core i5-11600K. It was only weeks later we caught up with the brilliantly priced Core i5-11400F, and we are now looking at the Core i7—a brand that represented the top-end from Intel until as recently as the Core i7-8700K. Intel introduced the Core i9 moniker to the mainstream-desktop segment to better tackle the AMD Ryzen 7 series.

Intel had until now differentiated the Core i7 and Core i9 parts using core/thread counts. The i7-9700K was an 8-core/8-thread processor, while the i9-9900K was 8-core/16-thread, and the i7-10700K was an 8-core/16-thread part, while the i9-10900K was 10-core/20-thread. With “Rocket Lake,” and its new higher-IPC “Cypress Cove” CPU cores being built on existing 14 nm process, Intel can no longer cram more than eight of the larger cores plus an iGPU into the LGA1200 package. The company hence settled on 8-core/16-thread for even its top i9-11900K part, hoping that the claimed 19% IPC gain would see the chip through. Here, the company hit the problem of how to carve out the Core i7 part. In the end, the company chose to keep the exact same core configuration as for the i9-11900K—8-core/16-thread.

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What sets the Core i7-11700K and i7-11700KF apart from the i9-11900K/KF is a combination of slightly lower clock speeds and the lack of Thermal Velocity Boost and Adaptive Boost. While Thermal Velocity Boost is essentially an additional Turbo multiplier when thermals allow, Adaptive Boost was in our i9-11900K review noted to be an interesting feature that unlocks additional boost bins across all workload thread-counts, especially higher-threaded ones. The i7-11700KF is still unlocked, and you get the same overclocking capabilities as the Core i9. For the past couple of generations, Intel has released SKUs with the “F” brand extension in the retail channel, like the i7-11700KF we’re reviewing here. These chips come with disabled iGPUs, letting Intel utilize dies with faulty graphics cores and price them about $10–$20 lower. These make for a nice deal for gamers who rely on graphics cards. Technically, the iGPU is still part of the silicon die,and takes up space; it’s just sitting there, disabled permanently.

The 11th Gen Core processors debut the “Rocket Lake” microarchitecture. Although built on the same 14 nm silicon fabrication process, it innovates in four key areas. First, it packs up to eight “Cypress Cove” CPU cores. These are a back-port of “Sunny Cove” to the 14 nm node, and Intel claims they come with an IPC gain of up to 19%. Next up is the new Gen12 Xe LP integrated graphics available on non-F SKUs, which are claimed to be up to 50% faster than the previous Gen9.5 cores. The third key area is the I/O, with Intel introducing PCI-Express 4.0 support. In addition to a PCI-Express 4.0 x16 slot, these chips put out one processor-attached M.2 NVMe slot with the Gen 4 x4 interface. The DMI chipset bus has doubled in bandwidth when paired with Z590 or H570 chipsets, too. Lastly, as we’ll detail in the following pages, the processors introduce many new ways of overclocking.

The Core i7-11700KF then is an 8-core/16-thread processor that lacks integrated graphics, but features an unlocked multiplier. It otherwise has the same clock speeds as the i7-11700K, with 3.60 GHz base frequency and 5.00 GHz maximum Turbo. Each of the eight cores comes with 512 KB of dedicated L2 cache, and they share 16 MB of L3 cache. The lack of integrated graphics has Intel price the i7-11700KF about $25 lower than the i7-11700K. It’s also a staggering $140 cheaper than the i9-11900KF and $170 cheaper than the i9-11900K flagship. In this review, we figure out if you could potentially save yourself $170–$180 by opting for the i7-11700KF over the i9-11900K, a price-difference that makes your motherboard “free.”

Intel Core i7-11700KF Market Segment Analysis

Price Cores /
Threads
Base
Clock
Max.
Boost
L3
Cache
TDP Architecture Process Socket
Ryzen 3 3300X $200 4 / 8 3.8 GHz 4.3 GHz 16 MB 65 W Zen 2 7 nm AM4
Core i3-10300 $180 4 / 8 3.7 GHz 4.4 GHz 8 MB 65 W Comet Lake 14 nm LGA 1200
Core i5-9400F $150 6 / 6 2.9 GHz 4.1 GHz 9 MB 65 W Coffee Lake 14 nm LGA 1151
Core i5-10400F $150 6 / 12 2.9 GHz 4.3 GHz 12 MB 65 W Comet Lake 14 nm LGA 1200
Core i5-10500 $215 6 / 12 3.1 GHz 4.5 GHz 12 MB 65 W Comet Lake 14 nm LGA 1200
Core i5-11400F $170 6 / 12 2.6 GHz 4.4 GHz 12 MB 65 W Rocket Lake 14 nm LGA 1200
Ryzen 5 3600 $200 6 / 12 3.6 GHz 4.2 GHz 32 MB 65 W Zen 2 7 nm AM4
Core i5-9600K $215 6 / 6 3.7 GHz 4.6 GHz 9 MB 95 W Coffee Lake 14 nm LGA 1151
Core i5-10600K $230 6 / 12 4.1 GHz 4.8 GHz 12 MB 125 W Comet Lake 14 nm LGA 1200
Core i5-11600K $275 6 / 12 3.9 GHz 4.9 GHz 12 MB 125 W Rocket Lake 14 nm LGA 1200
Ryzen 5 3600X $250 6 / 12 3.8 GHz 4.4 GHz 32 MB 95 W Zen 2 7 nm AM4
Ryzen 5 5600X $350 6 / 12 3.7 GHz 4.6 GHz 32 MB 65 W Zen 3 7 nm AM4
Core i7-9700K $290 8 / 8 3.6 GHz 4.9 GHz 12 MB 95 W Coffee Lake 14 nm LGA 1151
Core i7-10700K $320 8 / 16 3.8 GHz 5.1 GHz 16 MB 125 W Comet Lake 14 nm LGA 1200
Core i7-11700KF $390 8 / 16 3.6 GHz 5.0 GHz 16 MB 125 W Rocket Lake 14 nm LGA 1200
Core i7-11700K $420 8 / 16 3.6 GHz 5.0 GHz 16 MB 125 W Rocket Lake 14 nm LGA 1200
Ryzen 7 3700X $330 8 / 16 3.6 GHz 4.4 GHz 32 MB 65 W Zen 2 7 nm AM4
Ryzen 7 3800XT $450 8 / 16 3.9 GHz 4.7 GHz 32 MB 105 W Zen 2 7 nm AM4
Ryzen 7 5800X $450 8 / 16 3.8 GHz 4.7 GHz 32 MB 105 W Zen 3 7 nm AM4
Core i9-10850K $385 10 / 20 3.6 GHz 5.2 GHz 20 MB 125 W Comet Lake 14 nm LGA 1200
Core i9-10900 $400 10 / 20 2.8 GHz 5.2 GHz 20 MB 65 W Comet Lake 14 nm LGA 1200
Ryzen 9 3900X $485 12 / 24 3.8 GHz 4.6 GHz 64 MB 105 W Zen 2 7 nm AM4
Ryzen 9 5900X $550 12 / 24 3.7 GHz 4.8 GHz 64 MB 105 W Zen 3 7 nm AM4
Core i9-9900K $370 8 / 16 3.6 GHz 5.0 GHz 16 MB 95 W Coffee Lake 14 nm LGA 1151
Core i9-10900K $470 10 / 20 3.7 GHz 5.3 GHz 20 MB 125 W Comet Lake 14 nm LGA 1200
Core i9-11900K $550 8 / 16 3.5 GHz 5.3 GHz 16 MB 125 W Rocket Lake 14 nm LGA 1200

Unboxing and Photography

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The Core i5-11400F ships in a simple paperboard box with a small cutout to see the processor. The box contains the processor only, a cooler is not included.

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The processor is based on the same Socket LGA1200 package as 10th Gen Comet Lake and will work on not just Intel 500-series chipset motherboards, but also older 400-series ones, with a BIOS update.

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Intel’s Socket LGA1200 uses the same mounting-hole layout as the older LGA115x configuration, giving you a huge choice in coolers. Just be sure it can handle a TDP of at least 125 W.

The Rocket Lake Microarchitecture

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The new Rocket Lake microarchitecture forms the bedrock of Intel’s 11th Gen Core desktop processor family. The architecture aims to introduce some of Intel’s latest CPU and iGPU architectures to the desktop platform. It also brings Deep Learning Boost AI acceleration to this form factor, and AVX-512. With Rocket Lake, Intel aims to introduce their first double-digit, single-threaded CPU performance gains in five years, and a massive iGPU performance gain over the previous generation.

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The Rocket Lake-S die is built on what is hopefully the final refinement of Intel’s 14 nm silicon fabrication process. Why Intel didn’t go with 10 nm SuperFin is anyone’s guess. The company still seems to be transitioning between 14 nm and 10 nm-class nodes and is currently prioritizing mobile and enterprise processors with the new node. The price Intel pays for sticking with 14 nm does not just consist of power/thermal costs rivaling 10th Gen Comet Lake. CPU cores are also limited to a maximum of eight since the LGA1200 package has limited fiberglass substrate area.

Rocket Lake combines five key design enhancements over the previous generation. These are the new Cypress Cove CPU core, new Gen12 Xe LP integrated graphics, new Gaussian Network Accelerator (GNA) 2.0—a hardware component that enables the Deep Learning Boost (DLBoost) AI acceleration feature—AVX-512, and, lastly, the updated platform I/O that introduces PCI-Express 4.0, along with a chipset bus with double the width over the previous generation.

Cypress Cove

The new Cypress Cove CPU core is a back-port of the “Sunny Cove” core found in Ice Lake processors, to the 14 nm silicon fabrication node. Sunny Cove was originally designed for Intel’s 10 nm node. Intel hasn’t released core architecture documentation specific to Cypress Cove, but we can extrapolate from what precious little information Intel put out for Sunny Cove.

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A CPU core has essentially three components—the front-end, a part that understands the nature of the work and allocates the right hardware resources to get it done; the Execution stage, where the actual number-crunching happens; and the Load/Store stage, which interfaces this work done/to-be-done with the memory system through the processor’s cache hierarchy. Intel appears to have directed its engineering efforts toward improving the Execution and Load/Store stages.

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There are numerical increases in key components that make up the Execution stage of the core: 25% more allocation width and execution ports, 33% more AGUs, and an additional Store unit in Load/Store. These changes enable support for newer instruction sets—prominently, 512-bit AVX (or AVX-512). Rocket Lake being a client microarchitecture, receives a truncated version of AVX-512 with only those instructions that are relevant to the client segment. The cache sub-system receives a much needed update with the L1 Data cache being enlarged to 48 KB (from 32 KB on Skylake) and the L2 cache being doubled in size to 512 KB. At 16 MB, the L3 cache size hasn’t been changed from the previous-generation 8-core parts.

Intel Xe Graphics

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The next major component is the Intel Iris Xe integrated graphics solution based on the latest Gen12 Xe LP graphics architecture. This is the same exact technology as in the Tiger Lake iGPUs, but with a slight difference. While the Tiger Lake iGPU gets 96 execution units as shown in the slide above, the Rocket Lake iGPU only has 48. This was probably done to conserve silicon real-estate on the 14 nm die. Intel attempted to make up for the deficit in EUs compared to Tiger Lake by running the iGPU at higher engine clocks and a more generous power budget than the 15-watt Tiger Lake chips launched so far. In any case, Intel claims that the iGPU on Rocket Lake performs up to 50% faster than the Gen9.5 solution found in Comet Lake. Intel updated the media engine of the iGPU to now offer hardware-acceleration of 10-bit AV1 and 12-bit HEVC video formats.

AVX-512

With this generation, Intel is introducing the new AVX-512 instruction set. This evolution of AVX and AVX2 helps accelerate SIMD workloads—similar operations on a lot of data at the same time. The whole AVX-512 instruction set is a vast set of instructions, not all of which are relevant to the client PC use case. Intel has hence truncated the instruction set, with only certain instructions available to client platforms such as Rocket Lake and Ice Lake, while enterprise/HPC products, such as Xeon Scalar processors and Xeon Phi, have different instructions. Since Cypress Cove is derived from Sunny Cove (and not “Willow Cove”), it features Foundational (F), Conflict-Detect (CD), Vector Propulsion Count (VPOPCNTDQ), Vector Length (VL), BFloat16, Vector-AES, etc., but not the Vector Intersect (VP2INTERSECT) instruction Willow Cove supports.

Gaussian Network Accelerator

Next up is GNA 2.0, the hardware component that enables DLBoost, Intel’s ambitious new client processor feature that brings AI capabilities to their processor to speed up certain creativity apps that can leverage them. AI-accelerated video and image manipulation has made great strides on smartphones for the past 3+ years, and Intel sees an opportunity for it on the PC, too. DLBoost debuted in 2019 with the 10th Gen Ice Lake mobile processors and is coming to desktop with Rocket Lake. Intel claims that it accelerates deep-learning neural net building/training by up to six times compared to native x86 machine code, which can help offload the CPU cores.

作者 frank

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