Intel Core i7-7700K Kaby Lake review

With identical performance to Skylake, Intel brings desktop performance to a standstill.

The Intel Core i7-7700K is what happens when a chip company stops trying. The i7-7700K is the first desktop Intel chip in brave new  world—which means that instead of major improvements to architecture, process, and instructions per clock (IPC), we get slightly higher clock speeds and a way to decode DRM-laden 4K streaming video. Huzzah.

For the average consumer building or buying a new performance-focused PC, a desktop chip based on 14nm  remains the chip of choice—a total lack of competition at this level makes sure of that.

But for the enthusiast—where the latest and greatest should perform better than what came before—Kaby Lake desktop chips are a disappointment, a stopgap solution that does little more than give OEMs something new to stick on a label in a 2017 product stack.

 

SPECS AT A GLANCE: INTEL CORE I7-7700K
ARCHITECTURE	Kaby Lake
CORES/THREADS	4/8
CORE CLOCK	4.2GHz
BOOST CLOCK	4.5GHz
L3 CACHE	8MB
MEMORY CONTROLLER	Two channel DDR4
TDP	91W
PRICE	£330/$350

What's new?

Which is not to say that the whole of the Kaby Lake lineup is a bust. There are some performance gains to be had further down the product stack, particularly in the graphics department. 15W U-series processors for thin-and-light laptops feature new Intel Iris Plus graphics, which promise as much as a 65 percent performance boost over older Intel HD graphics, while the more mature 14nm manufacturing process (dubbed 14nm+) promises better battery life. 45W H-series chips for laptops are unlocked for overclocking, and there's the new Core i3-7350K, an unlocked dual-core processor with hyperthreading for overclocking on the cheap.

KNOW YOUR CODENAMES
CODENAME AND YEAR	PROCESS	PROMINENT CONSUMER CPU BRANDING	TICK/TOCK
Westmere (2010)	32nm	Core i3/i5/i7	Tick (new process)
Sandy Bridge (2011)	32nm	Second-generation Core i3/i5/i7	Tock (new architecture)
Ivy Bridge (2012)	22nm	Third-generation Core i3/i5/i7	Tick
Haswell (2013)	22nm	Fourth-generation Core i3/i5/i7	Tock
Broadwell (2014-15)	14nm	Fifth-generation Core i3/i5/i7, Core M	Tick/"Process"
Skylake (2015-16)	14nm	Sixth-generation Core i3/i5/i7, Core m3/m5/m7	Tock/"Architecture"
Kaby Lake (2016-17)	"14nm+"	Seventh-generation Core i3/i5/i7, Core m3	"Optimization"
Cannonlake (2017?)	10nm	TBA	"Process"

The quad-core i7-7700K, which sits at the very top of the Kaby Lake lineup, is less interesting. Compared to the sixth-gen i7-6700K Skylake processor that preceded it, the i7-7700K gains a small bump in base and boost clocks to 4.2GHz and 4.5GHz respectively, as well as the deceptively named Intel HD Graphics 630. The latter, while new in name, is largely identical to the Intel HD Graphics 530 found in the i7-6700K. There are no major architectural changes, and it runs at the same 1150MHz clock speed. What you do get is support for 4K media decoding inside Windows 10's PlayReady 3.0 DRM, which makes 4K Netflix possible on PC.

Kaby Lake motherboards are much like Kaby Lake processors: there's little of the way of actual performance improvements. Useful for storage fans, however, is the addition of four extra PCIe lanes to the top-end Z270 and Q270 chipsets, for a total of 24. With high performance storage having moved to the PCIe interface over SATA (see the NVMe-based Samsung 950 Pro), PCIe lanes are quickly becoming scarce. Combined with the 16 PCIe lanes on the processor, a Kaby Lake system now sports a total of 40 PCIe lanes.

Up to six SATA 3.0 ports are supported by the Intel chipset, along with a total of 14 USB ports (2.0 and 3.0), three PCIe 3.0 storage slots, and three independent displays when using integrated graphics. Any other features are manufacturer specific.

The spectacularly l33t gamer ASUS ROG Maximus IX Code, for instance (as used to benchmark the i7-7700K for this review), features an extra pair of USB 3.1 ports (one Type-A one Type-C) on the rear via an additional Asmedia controller. Interestingly, Asus has also placed a USB 3.1 header on the board itself for use with front panel Type-C connectors. Unfortunately, since this header is non-standard, only a handful of cases from Lian-Li and In-Win actually support it.

Elsewhere, there are the usual array of Asus enhancements, including its excellent 2X2 802.11 a/b/g/n/ac MU-MIMO Wi-Fi, SupremeFX Audio S1220 solution (featuring a ESS Hi-Fi Sabre DAC), Intel I219-V Gigabit Ethernet chip, dual M.2 SSD slots, and enthusiast-friendly features like dedicated water pump headers, PMW/DC support across all five fan headers, and SLI support. Naturally, since it's now apparently a prerequisite for all enthusiast PC hardware, there's built-in RGB lighting tucked underneath the Code's hardy plastic cladding.

It's worth noting that the Code is but a small part of what is a huge, horribly confusing line-up of Z270 motherboards from Asus, each of which has an ever so slightly different price point and set of features. The Code sits near the top of the pile with a £307 price tag (the most expensive being the £554 Maximums IX Extreme), but prices go as low as £117 for the Prime 270-P. I've said it before and I'll say it again: the motherboard market is needlessly intimidating to new PC builders. How anyone is supposed to know whether to buy a Deluxe, a Code, or whatever without some serious research is a mystery. What's wrong with good, better, best?

5GHz and beyond

Still, Asus' reputation for rock-solid reliability and overclocking performance continues with the Code. It is a high-end motherboard with a high-end price to match, but it (along with several other Asus boards) has a neat party trick: it can push the i7-7700K to 5GHz with a reasonable (read: no extravagant water cooling required) setup. There are a few caveats to that performance—the biggest being that Asus also supplied the i7-7700K for this review, which was likely binned from a large batch—but the company claims that most decent unlocked Core i7 and Core i5 Kaby Lake chips will hit 5GHz between a reasonable 1.29-1.35 volts.

To that end, I've included 5GHz benchmarks for the i7-7700K, as well benchmarks for stock speeds. The Code and i7-7700K were paired with 32GB of 3200MHz HyperX memory, as well as a Corsair H100 for cooling. Since the i7-6700K is also compatible with the Code, all benchmarks for that chip were run with under the exact same setup. In order to take clock speed out of the equation, I also ran benchmarks with the i7-6700K overclocked to the same 4.2GHz and 4.5GHz speeds of the Kaby Lake chip (a speed bump small enough to require nothing more than changing the multiplier in the BIOS).