In 1978, the Intel 8086 was, by today's standards, just an unassuming chunk of silicon with a ceramic substrate standing atop a mere 40 pins.
But this tiny chip launched the juggernaut of IBM PCs and compatibles that catapulted computing from universities and governments to businesses and households.
It's not hyperbole to say that every connected device today shares a few lingering strands of DNA with Intel's 29,000-transistor 8086.
To celebrate the 40th anniversary of that historic CPU's arrival on the market, Intel launched a special Limited Edition 8th Generation Core i7 processor (50,000 will be offered) that tips its hat to those early days of the computing revolution and the rise of the x86 architecture.
Is there more to the Intel Core i7-8086K ($425) than just pent-up nostalgia? In short: Yes, but mainly for overclockers, or PC builders who want the cachet of a special slice of silicon.
The Core i7-8700K that it strongly resembles remains a better-value alternative.
The New Ceiling for 8th Generation Core
Under its heat spreader (which still relies on the oft-maligned "TIM" thermal interface material instead of solder), the Intel Core i7-8086K is an LGA 1151 processor from Intel's "Coffee Lake" family.
It features six cores and 12 threads, the latter thanks to Intel Hyper-Threading support.
On the die is 12MB of Intel Smart Cache, a dual-channel memory controller, and the familiar Intel UHD Graphics 630 integrated video acceleration with a 350MHz minimum and 1.2GHz maximum GPU frequency.
The memory controller is rated to support up to DDR4-2666 memory; memory kits running at these speeds are, by current standards, rather poky, however.
Despite this number, Intel's latest Core i7 and i5 processors support memory that can clock to up to and beyond 4,000MHz with a little tweaking.
Case in point: The G.Skill DDR4 kit I'm using runs at DDR4-3400 speeds, and all that I had to do was enable an XMP profile from within the BIOS to get it there.
AMD's competing processors don't have quite the same universal support for high-clocked DDR4 memory, but as of the second-generation Ryzen processors (such as the recently reviewed Ryzen 7 2700X ($421.99 at Amazon) ), support for higher-clocked memory is improving on the platform.
Support for AVX2, QuickSync, and Optane Memory (the last for caching your hard drive to achieve semi-SSD speeds), as well as an unlocked multiplier like the rest of the K-series chips, round out some of this processor's most notable features.
(Credit: Intel)
Core i7-8700K Versus 8086K
At the—ahem—core, the Core i7-8086K is essentially a "binned" (factory pre-selected) Core i7-8700K chip that's been verified for higher tolerances.
So, what separates this processor from the vanilla Core i7-8700K? Clock speed.
At 4GHz and 5GHz, respectively, both the base and max Turbo clocks of the Core i7-8086K are 300MHz higher than those of the Core i7-8700K ($353.70 at Amazon) .
Despite what it says on the box, though, the actual per-core Turbo clocks between the two processors are identical until you get to just a single active core.
What does that mean? When all six cores are active and maxed out, both chips will operate at 4.3GHz.
When five or four cores are active, the clocks go up to 4.4GHz.
Three active cores can clock up to 4.5GHz, and two cores go to 4.6GHz.
For strict single-core workloads, the Core i7-8700K can increase the speed of that core to 4.7GHz, while one active core on the Core i7-8086K will surge to 5GHz.
That's undeniably an impressive number, but in 2018, single-core workloads are becoming increasingly antiquated.
Deja Vu All Over Again
Rather than spend a lot of time rehashing the details of Intel's Coffee Lake architecture, which is itself a modest tweak of the 7th Generation "Kaby Lake" design, and that in turn a minor revision of 6th Generation "Skylake," I'll just refer you again to our Intel Core i7-8700K review.
That review goes into much greater detail; in short, though, compared to Kaby Lake chips, the 8th Generation processors built on a 14nm++ node have more cores (up to six), more Intel Smart Cache (up to 12MB), and some other enhancements meant to ease overclocking and keep the processor within its 95-watt TDP.
This chip, despite the more powerful operating frequency, works with all the same chipsets and motherboards as the rest of the 8th Generation Intel processors.
Buyers who understand the power of this processor will likely want to pair it with a Z370-based mainboard, along the lines of a Gigabyte Z370 Aorus Gaming 7 ($450.00 at Amazon) or MSI Z370 Gaming Pro Carbon AC.
Note that boards that have been on the shelf a while, though, may need a BIOS update before they can recognize the Core i7-8086K, as the chip launched later than the rest of the platform.
If the board can't do an update without POST-ing, you may need an earlier CPU to get you into the BIOS in the first place to do the update.
Testing Methodology
Before I dug into the overclocking performance of the Intel Core i7-8086K, I ran a number of tests to determine how this processor performs at its default settings.
For my test setup, I installed the Intel Core i7-8086K into an Asus ROG Strix Z370-I Gaming ($476.86 at Amazon) Mini-ITX motherboard, and populated two of the DIMM slots with 16GB of dual-channel G.Skill SniperX DDR4-3400 memory.
For the Windows 10 boot drive, I relied on a 240GB Crucial BX300 SATA SSD.
I installed the components into a SilverStone Redline Series RL06 ATX case and used the DeepCool Captain 240EX closed-loop cooler to flush heat away from the processor's integrated heat spreader (IHS).
It's important to note that the Intel Core i7-8086K does not include a stock CPU cooler, so you'll need to add one to your shopping list if you select this processor.
For the graphics card, I used an Nvidia GeForce GTX 1080, operating at the Founders Edition clocks.
Testing Stock Performance
To compare this processor's scores with some other key CPU options within pricing striking distance that are currently on the market, I included in the charts below scores for seven other chips.
The first is the six-core/12-thread Intel Core i7-8700K that's just a step down and on the same socket. Also in the Intel camp: the six-core/six-thread Intel Core i5-8400 ($219.85 at Amazon) (which does not benefit from the Hyper-Threading of the i7 chips).
And finally, I dropped in the numbers for the eight-core/16-thread Intel Core i7-7820X, a slightly more upscale ($599) chip on the enthusiast-minded Core X-Series platform.
For the AMD side of the aisle, I rounded up the numbers for four processors.
The eight-core/16-thread AMD Ryzen 7 2700X mentioned earlier is the closest current-gen competitor for the Core i7-8086K and the i7-8700K, while the eight-core/16-thread Ryzen 7 1800X is its equivalent first-gen-Ryzen counterpart.
I also dropped in the step-down six-core/12-thread Ryzen 5 2600X ($210.99 at Amazon) , another current-gen CPU.
And, for kicks, you'll see the much pricier 16-core/32-thread Ryzen Threadripper 2950X we recently reviewed for some higher-end context.
Cinebench R15
Maxon's 64-bit Cinebench R15 is a CPU-centric test that lets us gauge both the single-core and multicore performance of the various processors I tested.
The resulting scores are proprietary numbers that represent the processor's performance while rendering a complex CPU-intensive image.
This is considered a synthetic benchmark.
When it comes to this benchmark, higher core counts generally translate to higher scores.
So it's no surprise that when pitted against the eight-core (or 16-core, for that matter) processors from AMD, Intel's Core i7-8086K Limited Edition can't quite keep up.
When you look at the Cinebench single-core tests, however, this is where the Core i7-8086K really flexes its muscle.
In fact, this processor owns the top single-core score in this benchmark.
No surprise, given its lofty rated clock speed when only one core is in play.
iTunes 10.6 Conversion Test
The iTunes 10.6 Encoding Test is tragically single-threaded, which means that more cores simply don't make a dent on these workloads.
This test is designed to illustrate the performance you might expect when running legacy software that doesn't scale well across more than one core.
When you eliminate core count from the equation, clock speed becomes the next major player, and clock speed is what the Intel Core i7-8086K has in spades.
As a result, this chip again takes the crown, encoding the album in just a minute and 22 seconds.
Handbrake 0.9.9
Handbrake is a classic (and popular) workstation utility that's used to convert videos between formats.
Typically, the more threads and cores a processor has, the better it will perform in this utility.
I loaded up a 12-minute-long 4K video clip titled Tears Of Steel and used the software to convert it into a 1080p MPEG-4 video.
In this real-world test, the Core i7-8086K loses some ground to the processors with more cores, particularly the costlier Ryzen Threadripper 2950X and the Core i7-7820X.
If you do a lot of video editing, using applications that scale well across multiple cores and threads, there are better (and cheaper) options than the Core i7-8086K.
POV-Ray 3.7
The POV-Ray benchmark tasks the processor with rendering a complex photo-realistic image using ray tracing.
This benchmark is another one that's generally considered synthetic; however, the highly-threaded nature of the utility is getting to be more and more representative of the applications available today.
I ran POV-Ray using both the multi-threaded "All CPUs" setting and the hamstrung "One CPU" setting.
Once again, Intel's highly clocked single-core performance shines in the single-threaded benchmark, but when it comes to the multi-threaded test, Intel slips into AMD Ryzen 5 2600X territory.
Blender 2.77a
Another of the real-world benchmarks we used is Blender, a popular open-source 3D rendering application that people far more creative and talented than I use to craft 3D visual effects, animations, and models.
Our test file consists of a cartoonish flying squirrel render that takes less than a minute to complete with most modern processors.
AMD's first-generation Ryzen processors are lagging behind in the Blender benchmark.
As you might expect, the Intel Core i7-8086K is one of the fastest processors we tested, lagging by just a second behind the Core i7-8700K, close enough to be within the margin of error.
7-Zip File Compression
7-Zip is a widely used file-compression utility that features a built-in compression/decompression benchmark.
It is a real-world test that generally makes use of as many cores and threads as your processor has to offer.
Once again, when a workload tends to scale well across cores, the eight-core-and-higher processors will have an advantage against the Coffee Lake 8700K flagship and the Limited Edition processor.
That being said, the Core i7-8086K performs a good deal better than AMD's six-core processors, such as the Ryzen 5 2600X and 1600X.
Gaming Tests: Advantage, Intel
To determine how much our slate of processors helps or hinders a system in games, I ran the in-game benchmarks from the AAA titles Far Cry Primal (on the High preset) and Rise Of The Tomb Raider (DX11, Very High preset) at resolutions of 1080p and 4K.
The component doing the real heavy lifting is the Nvidia GeForce GTX 1080, installed into the primary PCI Express x16 slot.
The Core i7-8086K consistently achieved superior performance at 1080p resolution (1,920 by 1,080), and even among the other Intel processors, the 8086K was the best in Far Cry Primal.
In Rise of the Tomb Raider, at 1080p, the 8086K was just a couple of frames per second behind the 8700K, essentially a tie.
When we moved to testing at 4K resolution (3,840 by 2,160), the processor ceased to be a bottleneck, and in both games, scores were nearly identical no matter which processor we were using.
Once again, dedicated gamers who want to make the most of their graphics card should really leave 1080p behind in favor of 1440p or 4K, or get a high-refresh-rate monitor.
I did only cursory tests of the i7-8086K's integrated UHD Graphics.
It's a reasonable assumption that no one opting for a rarified enthusiast chip like this is likely to run it solely on the integrated graphics silicon.
That said, we saw frame rates a bit above 30fps in the older games Tomb Raider and Sleeping Dogs (at the Normal/Medium graphics presets) at 1080p.
Smoother frame rates required bouncing down the resolution, or the detail presets to their lowest settings.
It was all much in line with what we saw with the Core i7-8700K—in short, gamers will want a dedicated video card to complement this chip, end of story.
Pushing the Limited Edition to the Limit
When I first started digging into the Intel Core i7-8086K, I was curious to see how the processor could manage to be tangibly faster than the Core i7-8700K, while shipping with the same 95-watt TDP.
I ran AIDA64's stress test while watching the processor's power consumption in Core Temp, a temperature-monitoring utility, and noticed that 95 watts did seem to be a practical power limit for the chip.
After running the stress test, the processor never got warmer than 75 degrees C (maximum) and average temperatures under load were much closer to 59 degrees C.
At idle, the chip hovered around a nice, cool 30 degrees C.
As I mentioned above, benchmarks like the AIDA64 stress test will punish all six cores, which means the clock speed, while this chip is at its stock settings, never gets above 4.3GHz.
Although this is the practical limit for AMD's second-generation Ryzen processors, we already know that this processor can boost at least one core to a jaw-dropping 5GHz.
Let's see if we can't get to 5GHz on all of 'em.
To start, I hopped into the BIOS menu of the Asus ROG Strix Z370-I Gaming motherboard and raised the multiplier to 50.
After a series of reboots and tests, I settled on a core voltage setting of 1.28V, which is more than reasonable should I decide to make this clock speed a permanent setting.
Back in Windows 10, I noted a 33 degrees C idle temperature, then started up Core Temp and ran AIDA64 again to see how the boosted processor performs under load.
One of the first things I noticed was that the system was far exceeding the 95-watt TDP.
Under load, the 8086K consumed between 135 and 139 watts.
Temperatures for this overclocked processor were also a...
