Intel Core i7-8700K Review: A 6-Core Chip That Punches Far Above Its Weight

Today, Intel is unveiling its new Coffee Lake line of desktop CPU cores and its first mainstream desktop response to AMD’s Ryzen architecture since that platform launched in March. That’s not to say we haven’t seen some significant shifts in Intel’s desktop parts–in fact, even before today’s launch, we’ve seen more price drops and feature improvements from Intel in 2017 than at any point since at least 2011.

As we’ve previously discussed, the Core i7-8700K isn’t a new CPU architecture. It’s still based on the same Kaby Lake processors that debuted last January with the Core i7-7700K, which itself was a clock-boosted version of the Skylake architecture that launched with the Core i7-6700K. The new chip is built on Intel’s 14nm++ process, however, which offers a modest frequency increase and hopefully better power efficiency than the previous 14nm+. The Z370 chipset is similarly identical to the Z270 chipset, with the exception that it supports the new Coffee Lake CPUs, while the old Z270 hardware doesn’t. If you’re looking for a major architectural update with Coffee Lake, you’re going to be disappointed, but the core clocks have come up some despite adding two additional cores.

Intel’s Six-Core Evolution

At the same time, however, Intel’s decision to bring a six-core solution to market is a big deal. For most of the past seven years, Intel’s six-core processors have carried a hefty premium. In 2011, Intel released the Core i7-980 and i7-970, which offered six-core processors in the LGA 1366 form factor and were drop-in compatible with its original LGA1366 chipset, but only the Core i7-980 was less than $ 800, and it ran $ 583 at launch. Intel’s initial line of six-core chips post-Westmere held to this price point. In 2014, Intel introduced a new Haswell-based Core i7-5820K at $ 400, and it launched a six-core Broadwell-E at $ 434 in May, 2016. The company’s current Skylake-X six-core, the i7-7800X, has an MSRP of just $ 389, which puts it right in the Core i7-8700K’s price bracket.

Intel-8thGen

This progression makes the Core i7-8700K look a bit pedestrian at first glance, but there are two distinct differences between this core and the six-core chips Intel has previously launched. First, the Core i7-8700K has a much higher base and boost clock. The chart below shows how Intel’s lowest-end / cheapest six-core processors have stacked up against each other, going back to 2014 and Haswell-E.

Corei7-vs-Corei7

The 3.7GHz base clock is only about six percent higher than the 7800X, but the 4.7GHz boost frequency blows every other six-core chip out of the water, including older models not included here from Ivy and Sandy Bridge. While the all-core boost frequency is below 4.7GHz, that’s the case for every other six-core chip as well.

The second difference between the 8700K and Intel’s previous chips is while Coffee Lake requires a new motherboard, the boards themselves should be cheaper than Intel’s HEDT motherboards are. Intel Z270 motherboards start around $ 100 on Newegg, while X299 motherboards that support the full range of Intel’s X-Series chips as opposed to just the quad-core variants start at $ 215. The MSRP on our Asus Prime Z370-A is higher, at $ 169.99, but Asus’ HEDT-equivalent, the Prime X299-A is a $ 295 board. Either way, combine the cheaper motherboard costs with the Core i7-8700K’s lower price, and this is Intel’s cheapest six-core platform ever.

AMD: The Fly In Intel’s Ointment

If these launches had taken place in 2016 instead of 2017, this would be a straightforward, no-brainer of an article. The 8700K adds more cores and higher clock speeds. It’s obviously going to blow the 7700K out of the water, and while the 7800X features Intel’s higher-performing Skylake-SP architecture, high clock speeds have a performance advantage of their own. At the very least, we’d expect the Core i7-8700K to compete well against Intel’s six-core HEDT processor, provided the benchmark in question isn’t memory bandwidth-bound.

AMD’s Ryzen family complicates this situation for Intel. First, there’s the Ryzen 5 1600X, with a 4.1GHz boost clock, six cores, 12 threads, and a new $ 219 price point, though it’s not clear if AMD has cut prices across the board or if the reduction is temporary. Even at the official list price of $ 249, the Ryzen 5 1600X packs a serious punch in the performance-per-dollar category–at $ 219 it’d be an even stronger core. We’re assuming Intel has picked turbo clocks for the 8700K that’ll sweep the Ryzen 5 1600X in benchmarks, but the AMD chip is $ 110 to $ 140 cheaper.

Second, there’s an entire sale on AMD’s entire upper-end Ryzen 7 stack. Newegg shows the Ryzen 7 family at significantly lower prices for at least the next six days. Here’s how the current lineup breaks down (all prices current as of 10/04/2017):

Corei7-vs-AMD

Whether the $ 100 off the Ryzen 7 1800X is permanent or not, it’s the CPU to watch when it comes to multi-threaded match-ups at the top of the market. Sixteen threads versus 12 is still a 1.33x boost in total thread count, and while Intel has an edge in single-threaded performance, AMD isn’t sitting behind the Piledriver 8-ball anymore, and it picks up somewhat more performance from SMT than Intel does in well-threaded scenarios. Intel does, however, have an additional ace up its sleeves. Our tests show the Core i7-8700K is much more aggressive when it comes to its all-core turbo clocks; the chip holds a steady 4.3GHz all-core frequency. That’s 1.16x higher than the Ryzen 7 1800X or Ryzen 7 1600X. Combined with Intel’s known advantage in single-thread processing, and the Ryzen CPUs will have to hustle to make up the difference.

Test Configuration

We tested all of our systems with 32GB of DDR4-3200 in four sticks of 8GB each, with a GTX 1080 Ti GPU running Nvidia’s 384.94 drivers, with an Asus Prime Z370-A motherboard. There are a few things to be aware of as you page through our test results. First, while we’ve largely standardized on the same benchmark set throughout 2017, we’ve added three tests recently–a Qt compilation test, PCMark 10, and a separate physics processing test in Blender–that we don’t have earlier data for. Instead of omitting these from our test results, we’ve included them even though the comparative processors have many more cores and threads. Consider these three benchmarks an interesting look at how cores and clock speeds impact test results differently as opposed to a direct apples-to-apples comparison.

Our gaming benchmarks are listed below, though we’ve had to include a somewhat different suite of processors than in our other tests. The Ryzen 7 1800X, Core i7-6900K, Core i9-7900X, and Core i7-8700K all hit very different clock speeds and offer different core configurations, ranging from the “classic” Intel HEDT configuration (represented by the 6900K), the new Skylake-SP architecture with its larger L2 and small L3 (7900X), Intel’s latest desktop CPU with its high core clocks (8700K), and AMD’s Ryzen family. The 1800X is a good stand-in for the 1600X here; the two CPUs benchmarked very similarly in the 1600X’s game tests. Apologies for an earlier edit that said all game results were literally identical — one title, Hitman, does show some variation at 1440p.

AMD’s Ryzen 7 family isn’t as strong in 1080p as it is in 1440p and 4K, but 1080p, at this point, is a somewhat artificial test, at least when using a GPU as powerful as the GTX 1080 Ti. While we don’t intend to retire it entirely, it’s most useful now for measuring CPU architectural performance differences when new architectures make their debut. We did a round of 1080p testing when Ryzen 7 launched and we’ll use it again for architectural shifts in the future, but 1440p and 4K better capture where high-end gamers are likely to spend their performance dollar. Despite hitting a wide variety of L2 cache configurations, clock speeds, and core counts, AMD and Intel are well-matched in most gaming tests (Hitman is a bit of an exception, and the 8700K does particularly well in that test).

Conclusions

AMD has spent the last six months punching holes in Intel’s various product lines. While Ryzen 7 and 5 may not have held the single-thread performance crown, their relatively high clock speeds and excellent multi-threaded scaling gave Intel’s Kaby Lake and Broadwell-E a serious beat-down. AMD’s Threadripper 1950X is still far and away the fastest chip you can buy for $ 1,000, even compared with Intel’s Core i9-7900X. But as of today, there’s a new force to be reckoned with in the $ 350 to $ 400 CPU market, and it’s wearing Intel blue.

The Core i7-8700K’s combination of high clock speeds and high single-threaded performance allow it to punch well above its weight class. While the Ryzen 7 1800X wins more tests than it loses against the 8700K, it wins nearly all of those tests by thin margins. This isn’t unique to AMD; Intel’s Core i7-6900K is in almost exactly the same position. In fact, across our entire suite of testing, the gap between the 6900K and the 8700K is even narrower than the gap between Intel’s latest six-core and the Ryzen 7 1800X. Meanwhile, the poor 7700K is completely outclassed by every other CPU in multi-threaded workloads, and 7700K owners who bought that CPU for multi-threaded workloads are probably a bit ticked with Intel right now, considering their brand-new motherboards won’t take a Core i7-8700K. Kaby Lake-X has also been obviated by these CPUs, losing whatever marginal utility it might have offered to begin with. The move never made much sense, considering Kaby Lake-X CPUs couldn’t use the full features of the X299 platform they ran on, and anyone eyeing one of these systems is going to see better results with an 8700K instead.

Intel’s combination of best-in-class single-threaded performance and nearly-as-good multi-threaded performance makes the Core i7-8700K a better option than AMD’s Ryzen 7 1800X given the current prices for both processors. AMD will have a chance to flip the tables next year, assuming its Ryzen+ architecture refresh can hit higher clock speeds than the first generation Ryzen processors, but Intel has the overall lead today.

The news isn’t all bad for AMD, however. The Ryzen 5 1600X isn’t as fast as the Core i7-8700K, tending to lag behind it by 20-25 percent, thanks in no small part to the clock gap between the two CPUs (3.7GHz for the 1600X, 4.3GHz for the 8700K). What the 1600X has going for it is price. The Core i7-8700K is roughly 1.2x faster than the 1600X, but is 1.44x more expensive before any difference in motherboard cost is taken into account. At the $ 219 price the chip currently lists for on Newegg, the comparison is even more lopsided–1.64x more money, for roughly 1.2x to 1.3x more performance. We still expect the 6-core / 12-thread Ryzen 5s to compete well against Intel’s Core i5, and if you’re trying to maximize performance per dollar, we’d easily recommend the Ryzen 5 1600X over the Core i7-8700K. In fact, we’d recommend it as the best overall value AMD offers in the entire Ryzen family.

The desktop CPU market has been more dynamic in the past 10 months then the six years previous, combined, and we’re glad to see it. Intel may have reclaimed the top position in the desktop CPU market, but the Core i7-8700K is as strong as it is because Intel needed a core that would compete effectively against AMD’s top-end Ryzen CPUs. It’s no accident Intel suddenly figured out how to build a six-core mainstream desktop processor seven months after AMD’s Ryzen family started eating its multi-threaded lunch, just as it’s no accident Pentium cores came down with a case of Hyper-Threading in January, the cost of a 10-core CPU dropped by ~$ 800 in June, and Core i3s and Core i5s both packed on more cores as of today. Intel has delivered an exceptional six-core CPU in the Core i7-8700K, but AMD deserves a nod for forcing them to do it.

Let’s block ads! (Why?)

ExtremeTechGaming – ExtremeTech

Read previous post:
Hardaker tests positive for cocaine & will miss World Cup

England and Castleford Tigers full-back Zak Hardaker has been provisionally suspended after testing positive for cocaine and will miss the

Close