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Intel Core i7 8700k cpu shot

Intel Core i7 8700K Coffee Lake Desktop Processor Review

  1. Ryze-n-shine in front of a lake view and a cup of coffee!!…
  2. How its tested??
  3. Computing Benchmarks
  4. Memory Benchmarks Timing Preset Comparison
  5. Memory Benchmark 16 GB Vs 32 GB (2667 MHz)
  6. Overclocking Performance Analysis
  7. Power Consumption
  8. Discrete GPU Performance Analysis
  9. Turbo Clock Speed Analysis
  10. Conclusion
  11. Online Purchase Links
  12. View All

Disclosure: The Core i7 8700K was loaned by AORUS to test the Z370 Gaming 7 and therefore not provided by Intel or any of its third parties press contacts.

Intel eight generation Coffee Lake SKUs are based on 14nm manufacturing process. It uses the same socket LGA 1151 as its older brother Kaby Lake processors. There have been significant changes where its contact points are different between them. This resulted in incompatibility and an uproar within the community. We got a lot of information, mostly from leaks and previews. Conveniently leaked leaks. Intel is pushing Core i3 four core and 6 core for its mid to upper SKUs- some with six threads with i5 series and some with 12 threads under i7 series. Intel is calling these desktop SKUs as S series, though to be fair that’s just going to create confusion in the market. Interesting times are back to the CPU world now that AMD got its act together with Ryzen series SKUs. Smell the air, because the lake is filled with coffee!!

Coffee Lake + Intel Z370 Overview

The maximum display support is three. The Native USB support is between USB 3.1 Gen 1 and USB 2.0. It totals up to 10 USB 3.1 Gen 1 support and up to 14 USB 2.0. Naturally, they’re not going to be motherboard manufacturers to utilize a lot of USB 2.0 availability. At this point, we would have appreciated native support for USB 3.1 Gen 2. The standard native Native SATA III is provided for up to six devices.

The discrete PCIe distribution for the Intel Z370 is PCIe 3.1 x16/ x8 + x8/ x8 + X4 + x4. The platform supports Intel Optane memory, VT-d, Intel HD Audio, Rapid Storage, Rapid Storage for PCIe Storage, Intel Smart Sound and Intel Platform Trust Technology and Boot Guard.On paper, there is no difference. It even has the same package size of 23 x 24mm.

From the CPU, there are 16 PCIe 3.0 lanes while 24 of them are from the Intel Z370 chipset. The unit supports DisplayPort 1.2 and HDMI 1.4 from its on-chip. Its native memory support is up to 2667 MHz. This lane distribution is not different from the not-so-old at all Kaby Lake + Z270 platform. You cannot call it as a refresh if there wasn’t a difference between Kaby Lake and Coffee Lake. The main addition is that Intel assures better overclocking, better 14nm process, better power delivery, 2666MHz support, more smart cache and more cores.

Why the incompatibility issue?

For an 8 core 12 thread CPU, its TDP is 95 watts, compared to 91 watts on the Core i7 7700K viz. a four core eight-thread processor. But Intel says it has improved its power deliveries required to provide better overclocking, mostly for its six-core Core i5 variants. We already have Core i3 quad cores and Core i7 six cores. One subsetting that I’ve observed is the per-core overclocking.

Had the gap between Kaby Lake and Coffee Lake were wide enough, people wouldn’t have talked about it. But Ryzen came in like a wrecking ball and Intel had to do something by the time it can roll out eight core Coffee Lake CPUs. Yes, technicalities aside if Coffee Lake had compatibility with Z270 chipsets, retailers can afford to have attractive pricing for 200 series motherboards and bundle it with them. Apart from a bit of a sting, there’s no reason for 7 gen users to shift to 8th gen at all- same for 7th gen to Ryzen series.

8th Gen SKU Overview

When Kaby Lake SKUs were out, the variants were available between $117 for the Core i3-7300 all the way to $339 for a Core i7 7700K. The Coffee Lake series is between $ 117 Core i3 8100 to $ 359 with the Core i7 8700K. What I have is the Intel Core i7 8700K, the flagship six-core twelve thread desktop CPU, with a base clock of 3.7 GHz and boost up to 4.7 GHz. You’ll notice that between the variants there is a slight base clock reduction, but that’s pretty much it. The Core i7 8700K gives a 1 GHz turbo boost, leaving i7 7700K behind which has 0.30 GHz boost. Furthermore, this is a six-core twelve thread CPU Vs four core eight core with 12 MB vs 8 MB smart cache and higher memory frequency support.

Based on the current launch, there are going to be three unlocked SKUs, each of them belonging to the available series Core i3, Core i5 and Core i7. The Core i3 representing the four core-four thread models while the Core i5 that should be targetting a wide array of users has six core six threads. Core i7 has way more smart cache, threads and Turbo Boost. Even Core i7 8700 is special for those who may not be comfortable with overclocking as it provides up to 1.4 GHz boost. All you need is good cooling to help the CPU keep turbo as constant as possible during loads- or base clock speed and its multiplier to max via UEFI.

Comparison with 7th Gen Kaby Lake SKU

SKU Core i7 8700K Core i7 7700K
Architecture Coffee Lake Kaby Lake
Process 14nm process 14nm process
Base Clock 3.7 GHz 4.20 GHz
With Turbo 2.0 Clock 4.7GHz 4.50 GHz
Cores/ Threads 6/ 12 4 / 8
TDP 95 w 91 w
Intel Smart Cache 12 MB 8 MB
Max Mem Support Dual Channel
DDR4 2666 MHz
Dual Channel
DDR4 2400 MHz
Optane Support Yes Yes
Pricing
(At the time of launch)
$359 $339

You should also note Kaby Lake does not have ECC support, while Coffee Lake allows you to use them. Sounds very familiar, eh?

There are a reasonable (by Intel’s standards) differences between them, but what creates discomfort is the space of within a year between these generations. Kaby Lake and its 200 series chipsets were out since Q1 2017. This is the dawn of the Q4 2017. Ouch!

Comparison with the Ryzen series

Eventually, it boils down to this:

SKU Core i7 8700K Ryzen 7 1700X
Architecture Coffee Lake (Intel) Ryzen (AMD)
Process 14nm process 14nm Process
Base Clock 3.7 GHz 3 GHz
With Turbo 2.0 Clock 4.7GHz 3.7 GHz
Cores// Threads 6/ 12 8/ 16
Thermal Design Power 95 w 95 w
L3 Memory 12 MB 16 MB
Max Mem Support Dual Channel DDR4 up to 2667 MHz Dual Channel DDR4 up to 2667 MHz
Optane Support Yes NA
Pricing (At the time of launch) $ 359 $ 399

Face-to-face comparison, it doesn’t really look good for Intel. Same TDP, more cores more threads more L3 Cache favours AMD. Multi-threaded performance should also favour AMD, which at this point of the requirement by users is an important factor.

Unfortunately, I have limited information on both sides. Ryzen because we never got a desktop CPU from them or from the motherboard manufacturers. Same for Intel as we got this chip from Taiwan to review the Aorus Z370 Gaming 7. This gave a good room for me to review both the Z370 motherboard and the Coffee Lake. The only comparable number I have is from CPU-Z bench which scores the score from R7 1800x and the 1700X.

Even if there are some variants that look attractive, AMD has started to have some of its variants sold at a cheaper rate for a limited time.  But its also interesting to see manufacturers who make motherboards for both platforms usually market and make many variants of Intel Z370 motherboards from Day 1. Sure, Intel has better single thread performance and Intel Optane support. It would be nice if Intel could have managed to provide a bit more features- such as USB 3.1 Gen 2 native support.

Single Thread/Multi Thread

The Ryzen 7 series SKU R7 1700, R7 1700X and 1800X have its initial launch priced for $329, $ 399 and $499. But AMD gets an advantage of two added cores. While having an eight-core only for gaming makes no sense, it does when coupled with productivity or multi-tasking. AMD also tried to repackage it for gamers who also stream (and maybe record gameplay in the system at the same time?), giving that importance towards multi-core multi-thread performance.

The launch date was in late Q1 2017, which doesn’t give Intel any headroom to push eight core Coffee Lake right off the bat. Therefore it reaches a situation- either to alienate existing Kaby Lake users for incompatibility but give an upgrade choice for those who are using a much older platform ranging from AMD’s aged AM3+ platform to at best 4th generation Core series users. AMD will have Ryzen 2 series coming out next year. As pissed off you might be, this is the pace we will see in the desktop processor and chipset when there is a competitive duopoly system- and it is not as if your existing system would be obsolete- its just two cores short for the price where you bought it two quarters ago.

On-chip graphics

Intel has a bumped UHD 630 series on-chip graphics, an upgraded version of the HD 630. None of the AMD Ryzen have on-chip graphics, a very small and insignificant for mid to upper-level segments users- and in some scenarios. Eventually, AMD will come out with APUs.

The Aftermarket CPU cooler situation

This is interesting as I am helping one making up their mind between Ryzen 7 1700X and Ryzen 5 1600X against price equivalent variants of the Coffee Lake series.

Coolermaster_D92_71

At the end of the day, LGA 115x aftermarket CPU cooler support is a LONG one, while the socket mounts for AM3+ and AM4+ is different. More so, not all aftermarket CPU coolers- air or liquid- have a purchasable AM4+ kit, no matter how new the CPU coolers were. Some of them don’t even have a proper AM4+ kit as well. Some, like Noctua, manage very well with a proper bolt through kit. Liquid cooler makers at best rely on retention bracket system. Many of the CPU coolers are not cheap at all. Many of these CPU coolers are good enough for the newer CPUs if it wasn’t for a proper mounting. It is an interesting conversation. While it may not influence some type of people changing their platform upgrade plans….or would it?

Eight Core Coffee Lake?

It is rumored that by next year we should get eight core coffee lake and the Intel Z390 chipset motherboards. We’ll cross that bridge when we get there! Because just like now, the obvious discussion would be will the eight core Coffee Lake work with Intel Z370? Same conversation with Ryzen and Ryzen 2. So many CPU conversations!

Test System and Testing Methodology

The following setup is what’s used to test the MSI Z270 Krait Gaming motherboard:

Operating System Windows 10 64-bit Pro
Processor+ Cooler Intel Core i7 8700K + Noctua NH-U14S
Motherboard AORUS Z370 Gaming 7
RAM 16GB HyperX Savage DDR4
GPU AORUS RX 580 XTR 8G
OS Drive 240GB SanDisk Extreme II SSD
Secondary WD Red 3TB
PSU Thermaltake DPS-G Gold 750w
PC Case Lian Li A70F

This motherboard is tested with the Core i7 8700k. If you are interested to read its review which includes 32 GB, 2667 MHz configuration and even with graphics card performance, here you go! Enhanced multi-core performance is disabled by default.

The Benchmarks are as follows:

  • Computing Benchmarks

Benchmarks are done in stock settings with turbo enabled. No changes have been made in the BIOS except both CPU fans at high speed.

    • 7 Zip Benchmark
    • AIDA64- CPU and Memory Benchmark
    • Futuremark Benchmarks:
      • 3DMark Sky Diver and Fire Strike
      • PCMark 8 Benchmark
    • Video Encoding Benchmark
    • MP3 Encoding
    • Cinebench R15
  • Memory Benchmarks

    Presets:

  • 7 Zip Benchmark
  • 16 GB Test: 2133 MHz 15-15-15 @ 2T / 2400 MHz 13-15-15 @ 2T / 2666 MHz 13-15-15 @ 2T
  • 2666 MHz 13-15-15 @ 2T Test: 16GB Vs 32 GB

Benchmarks are done with Core i7 8700K @ 4.3 GHz. CPU fans set at High Speed.

Benchmark are as follows:

  • 7-Zip Compression and decompression benchmark
  • AIDA64 CPU and Memory benchmark
  • Futuremark Benchmark: PCMark 08, PCMark 10, 3DMark Benchmark
  • Bitcoin Mining Benchmark
  • Computational Benchmarks
  • Ocean Surface/ Particle Simulator Benchmarks
  • Cinebench R15 and 11.5 64-bit Benchmarks
  • Video Encoding Benchmarks (720p and 4K)
  • MP3 Encoding
  • Euler3D Benchmark
  • Overclocking Performance Analysis

    • 7 ZIP Benchmark
    • AIDA64 Benchmark
      • CPU Test
      • Memory Test
    • 3DMark Benchmark
    • PCMark 08 Benchmark
    • PCMark 10 Benchmark
    • Video Encoding
    • Cinebench R15 Benchmark
    • Cinebench 11.5 Benchmark
    • Temperature Analysis
  • Power Consumption

  • Discrete Graphics Card Performance with AORUS RX 580 XTR (with OC profile)

    • 3DMark Benchmarks
    • Game Benchmarks: DOOM OpenGL, ROTR DX12 Highest Setting, Hitman DX12 Highest Setting
  • Turbo Clock Speed Analysis

7-ZIP Benchmark

AIDA64 Benchmarks

CPU Benchmark
Memory Benchmark

Video Encoding Benchmark

MP3 Encoding Benchmark

Cinebench R15 Benchmark

In this test, we will be comparing 16 GB performance between JEDEC profile (2133 MHz 15-15-15 @ 25) with Profile 2 (2400 MHz 13-15-15 @ 2T) and Profile 1 (2667 MHz 13-15-15 @ 2T) using the Kingston HyperX HX426C13SB2K2/16 kits. Another kit is added to see the between with 16 GB and 32GB kits (2666 MHz 13-15-15 @ 2T).

Benchmarks are done with Core i7 8700K @ 4.3 GHz. CPU fans set at High Speed.

7Z Compression and Decompression benchmark

AIDA64 CPU Benchmark

AIDA64 Memory Benchmark

3DMark Benchmarks

PCMark 8 Benchmark

PCMark 10 Benchmark

Cinebench R 15 and 11.5 64-Bit Benchmarks

Video Encoding (Handbrake)

720p MKV to MP4 (6.49 GB) Very Fast 720 encoding preset and 4K MOV to MKV (13.7 GB) Legacy 4K present

Bitcoin Mining

Though CPU based mining is unlikely with bitcoins, its purpose is to see if the memory profiles give some advantage.

Computational Benchmarks

Set 1: Optical Flow; Face Detection

Set 2: Graphics; Video Composition

Ocean Surface/ Particle Simulation

MP3 Encoding (Audacity)

Audacity Project File to MP3 320kbps ‘Insanity Quality’ setting

Euler 3D Benchmark

In this test, we will be comparing 16 GB performance between JEDEC profile (2133 MHz 15-15-15 @ 25) with Profile 2 (2400 MHz 13-15-15 @ 2T) and Profile 1 (2667 MHz 13-15-15 @ 2T) using the Kingston HyperX HX426C13SB2K2/16 kits. Another kit is added to see the between with 16 GB and 32GB kits (2666 MHz 13-15-15 @ 2T).

Benchmarks are done with Core i7 8700K @ 4.3 GHz. CPU fans set at High Speed.

7Z Compression and Decompression benchmark

AIDA64 CPU Benchmark

AIDA64 Memory Benchmark

3DMark Benchmarks

PCMark 8 Benchmark

PCMark 10 Benchmark

Cinebench R 15 and 11.5 64-Bit Benchmarks

Video Encoding (Handbrake)

720p MKV to MP4 (6.49 GB) Very Fast 720 encoding preset and 4K MOV to MKV (13.7 GB) Legacy 4K present

Bitcoin Mining

Though CPU based mining is unlikely with bitcoins, its purpose is to see if the memory profiles give some advantage.

Computational Benchmarks

Set 1: Optical Flow; Face Detection

Set 2: Graphics; Video Composition

Ocean Surface/ Particle Simulation

MP3 Encoding (Audacity)

Audacity Project File to MP3 320kbps ‘Insanity Quality’ setting

Euler 3D Benchmark

7 ZIP Benchmark

AIDA64 Benchmark

CPU Test

Memory Test

3DMark Benchmark

PCMark 08 Benchmark

PCMark 10 Benchmark


Video Encoding


Cinebench Benchmarks

Temperature Analysis

Since I’ve used the Noctua NH-U14S with its default dual fan setup in full speed, it would be interesting to see how the temperatures are:

It should note that at the highest temperature running on the stock with the turbo, the clock speed of the Core i7 8700K was 4.3 GHz. So the temperature increase between 3.7 GHz with turbo and 4.3 GHz constant is insignificant. The real challenge comes when you use 5.0 GHz, especially with the motherboard’s UEFI preset which typically overvolts the processors.

System Power Consumption

The true beauty between the fourth generation and eight generation can be seen here. Even the Core i7 8700K overclocked with OC profile on the AORUS RX 580 XTR 8G, it still is well under i7 4790K stock with turning running with the graphic card with the same profile. The standby and load power difference between them is really impressive to look at.

3D Mark Benchmark

Benchmarks are done using Stock clocks with turbo enabled. CPU fans are set to full speed.

Game Benchmarks

Turbo clock speed analysis

What to take from Core i7 8700K?

That power draw with the 5 GHz overclock + overclock preset RX 580 8G is brilliant! I used the preset which pulled 1.30v for the 5.0 GHz. I am sure this can do better since its an ES chip, but I wanted to see how it will perform with the usual overvolted presets.

Intel is still rocking single-threaded performance. AMD Ryzen 7 series has a good advantage in the multi-threaded performance benchmarks compared to the i7 8700K. What I absolutely love about the Core i7 8700K is the overclocking potential, the significant bump in Turbo for stock clocks which stays at its peak clock during load efficiently (depending on the temperature and load, of course) and the power consumption compared to the much older generations.

I’ll admit my conclusions would be more on the spot if AMD India was willing to work. Alas, here we are!

Claiming those are small changes in the power delivery is an understatement. Then there is the silicon lottery factor- irrespective of what you buy if you get the one who the big 5.0 GHz on air. You can’t help but fall in love with the Intel i7 8700K if you are a long time enthusiast who’s been regularly using Intel CPUs for a long time. Then again it still cannot overshadow  R7 1700X and R7 1800X due to its multi-threaded performance advantage.

To delid or not to delid?

When you see a lot of YouTube videos about the Coffee Lake CPUs, you see a lot of them delidding it. That should be a concern for Intel because that’s become a common practice. You get tools to easily open them and even instructions to reseal them. Most swap them out the thermal paste for a better one or even liquid metal. Maybe Intel should explore the option to easily unclip the IHS without voiding the warranty. They had a good chance with the Coffee Lake series. Who else would buy the unlocked series SKUs? Let’s not forget Intel made a very bad impression where it recommended not-very-old used Core i7 7700K users not to overclock it. The DDR4 performance is also great compared to other platforms, but Core i5 is the four core four thread comparison so it is not a direct comparison.

Ryzen shine and smell the coffee!

Talking about eight core Intel Coffee Lake is useless. It is going to come with a new Intel Z390 chipsets so you have to doubt its compatibility with Z370. Same for Ryzen 2. But if these people are at each other’s throats then we should see a good amount of competition and option every once in eight to twelve months.

If the Core i5 series is good enough to give a tough battle to Ryzen 5, that would be something to watch. Of course, the motherboard and processor pricing at the time will play a role. One small advantage is if you have an LGA 115x compatible CPU cooler already which doesn’t have an AM4 bracket. That might be a lame reasoning but many CPU coolers are expensive even till date. Then again, so is the Core i7 8700K against the Ryzen 7 series. Then again, brackets are cheap!

Intel has Optane and Rapid Storage technology, apart from the power delivery. Also by the looks of it, all motherboards makers have a wide variety of Intel Z370 motherboards, even possibly more than what we have from AMD. Plus- on-chip graphics. No big deal for mid to high-end users, but hey if your graphic card goes bad you won’t be left hanging.

Great little chip which has a big cloud over it called Ryzen. It is a good morning to have some coffee!


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2 comments

  1. Everytime I am here, I learn something new!

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