Core i7-8700K Review: Coffee Lake Brews A Great Gaming CPU

The Z370 Chipset & Graphics

The Z370 Chipset

Much to the dismay of enthusiasts everywhere, you can't buy a Coffee Lake-based CPU and drop it into the fancy Z270 motherboard you may have purchased a few months ago. Instead, you'll have to pony up for a 300-series motherboard. You also can't bring your Skylake or Kaby Lake processor over to a Z370-based platform, even though both sides employ LGA 1151 interfaces.

Intel makes more money selling CPUs than chipsets, so creating an upgrade path would have made sense. But the company tells us that it needed optimized memory trace routing to support DDR4-2666, and it also improved power delivery to support six-core models. It also beefed up package power delivery for overclocking.

According to Intel's specification sheet, the increased package power delivery consists of 18 pins repurposed to VCC (previously designated as reserve pins). There are also changes to the socket that reassign behaviors to some pins, such as swapping Normal Open (NO) and Normal Closed (NC) settings. Intel also improved power delivery to the graphics engine, and although the specific changes there remain undefined, that might improve HD Graphics overclocking.

The changes mean upgrading to Z370 is a technical necessity, rather than planned obsolescence. Regardless, though, AMD's planned support for Socket AM4 through 2020 makes Intel's Z370 chipset requirement appear all the more painful.

CPU-based I/O remains unchanged from Kaby Lake; you still get 16 lanes of PCIe 3.0. Again, though, the whole platform supports up to 40 lanes. The extra 24 originate from the PCH, stuck behind a four-lane DMI 3.0 connection that links the core logic and CPU. As you might imagine, this PCIe-like interconnect can become a bottleneck if enough devices (like M.2 SSDs) are working behind it.

The 22nm Z370 chipset is rated at 6W, and is mostly identical to Z270. It offers up to 10 USB 2.0, 14 USB 3.0, and six SATA 6Gb/s ports. Intel added support for Thunderbolt 3, but hasn't provided much detail on the implementation. Z370 also retains support for Intel Optane Memory. Even the ME version 11 is listed similarly on Intel's ARK, though we do know that Z370's Management Engine doesn't allow Kaby Lake processors to boot on the platform. Two memory channels support up to two DIMMs per channel and a maximum of 64GB. Intel does not support ECC on any of its models (compared to AMD, which does allow motherboard vendors to enable ECC support).

Intel offers a few unique benefits to enthusiasts, such as the XTU (Extreme Tuning Utility) and support for XMP 2.0. The Performance Tuning Protection Plan is also available, which covers damage from overclocking. The price for the warranty plan varies per SKU, and Intel hasn't provided a detailed breakdown for Coffee Lake yet. We aren't aware of any AMD-equivalent coverage.

Intel UHD Graphics 630

Intel will have an optimized graphics driver soon after launch, but we don't see any significant improvements (beyond HDCP 2.2 support for DP 1.2a) to the Gen 9 LP (Low Power) engine. We still get subslices with eight EUs each (totaling 24 EUs in a GT2 configuration), accelerated slightly by a 50 MHz maximum frequency increase across the board.

The biggest change comes from Intel's marketing department, which "upgraded" the High Definition (HD) Graphics 630 brand to Ultra High Definition (UHD) Graphics 630. Apparently, that means the company supports the same legacy VP8 and AVC codecs, HEVC 10-bit decode/encode, VP9 8/10-bit decode, VP9 8-bit encode (no support for VP9 10-bit encode), HDR, and Wide Color Gamut features. The processors now come in 6+2 (i5 and i7) and 4+2 (i3) configurations.

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162 comments
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    Top Comments
  • FormatC
    Anonymous said:
    Nearly 90 degrees Celsius when overclocked gaming on an AiO. Prettttttty toasty!

    The reason is simple:
    The built-in frying fat between IHS and die :)
    15
  • FormatC
    @LilDog1291:
    A delidded i7-8700K is around 15-20 degrees cooler. The problem isn't the architecture, but the TIM instead of solder.
    12
  • ingtar33
    this article is filled with subtle comments about all the extra stuff they needed to do to keep this thing from melting through the floor.

    If you had to take all these extra steps on an AMD cpu you'd have written an expose on how hot the chip is. But you just brush it off like its nothing in this article.

    BTW: if you can't run prime95 for half a day stable on an overclock, it's not a real overclock. It's just a silly benching number. Check my sig. Thats a silly benching number. Could I get a fx8320 to run at 5.3ghz? sure, windows booted and i validated it. But could I DO anything with that clock speed? nope. I've seen a number of review sites today post 5.0-5.1 ghz overclock numbers for coffee lake, yet not a single one of them could run a serious prime run on those numbers. Heck, can you even run prime at stock on this chip? I'd like to know that before I consider this chip for purchase to replace my i5.
    12
  • Other Comments
  • cknobman
    Looks like it might be time for AMD to lower prices.

    AMD really has shaken Intel up, never would I have dreamed (before this year) I'd see Intels best gaming cpu (especially a K model) release at $360.
    5
  • AgentLozen
    AMD's price per core is still very strong. It struggles in gaming at 1080p but Tomshardware didn't provide data in 1440p or 4K.

    I'm not yet convinced that AMD is in trouble.
    9
  • saunupe1911
    Hmmm is it worth a skylake 6700K that's stable at 4.6 Overclock to upgrade? Probably not. I wouldn't mind 6 cores though. I wonder how many will hit 5.0!
    2
  • jroc188
    8700k is $480ca got the R5 1600 for $255ca and mobo for $120ca. $375 all together and more then happy with the gaming results. But the 8700k dose look sweet on the benchmarks. AMD with a price drop will still sell well
    7
  • shrapnel_indie
    Quote:
    Of course, while Intel's accelerated Coffee Lake-S launch makes it look today's unveiling is a direct response to heated competition, in reality, the long incubation period for new processors means it’s more likely the result of 10nm manufacturing delays.


    Ummm... Yeah, the design may have been kicking around, and ready to go before Ryzen, but when it is released months earlier than scheduled.... Saying that it wasn't a response to Ryzen seems more like misinformation more than pure fact. Yeah, I don't doubt 10nm manufacturing delays played a part in the previous release date, but Ryzen forced its release a little earlier than planned.
    10
  • Billy Gates
    Intel caught AMD with their pants down. Panic mode incoming!
    -14
  • bloodroses
    To AMD fanbois who claimed that Intel was toast and couldn't respond to Ryzen's release, here's Intel's Mic drop. *thud*

    For the rest of us consumers, this is great news for continued strong competition at reduced prices from both companies. :)
    -5
  • massacre.h4te
    Nearly 90 degrees Celsius when overclocked gaming on an AiO. Prettttttty toasty!
    4
  • saunupe1911
    Anonymous said:
    To AMD fanbois who claimed that Intel was toast and couldn't respond to Ryzen's release, here's Intel's Mic drop. *thud*

    For the rest of us consumers, this is great news for continued strong competition at reduced prices from both companies. :)


    Z370 motherboards are expensive though...sheesh. And you gotta reach out to liquid cooling companies for attachments for mounting to this socket. Canon Lake may be out before you can get everything situated for a nice 8700k upgrade lmao.
    2
  • FormatC
    Anonymous said:
    Nearly 90 degrees Celsius when overclocked gaming on an AiO. Prettttttty toasty!

    The reason is simple:
    The built-in frying fat between IHS and die :)
    15
  • LilDog1291
    Anonymous said:
    To AMD fanbois who claimed that Intel was toast and couldn't respond to Ryzen's release, here's Intel's Mic drop. *thud*

    For the rest of us consumers, this is great news for continued strong competition at reduced prices from both companies. :)


    I don't know if I would call 90C+ on a chiller cooler (granted its a high overclock but the 7700k had the same problem) a mic drop but it is definitely a step in the right direction. If they can get their temperatures under control in the next generation they will win my vote back.
    3
  • Billy Gates
    Intel caught AMD with their pants down. Price drop is imminent.
    -8
  • FormatC
    @LilDog1291:
    A delidded i7-8700K is around 15-20 degrees cooler. The problem isn't the architecture, but the TIM instead of solder.
    12
  • garba78
    Disappointed :(
    0
  • madmatt30
    @Billy Gatez - Its $360 , amd have no reason whatsoever to drop their prices at the moment.

    The ryzen 1600 is less than $200, Intel don't have an answer to that pricepoint .

    The only chips that should (& will) worry amd is the cheapest locked quad i3 , & the cheapest locked 6 core i5

    Nothing else is relevant to them price wise.
    4
  • JCFca1992
    I have a 6600K which I can't overclock past 4.2ghz without lots of heat (lost the Silicon Lottery).

    I play lots of 64 player BF1 and regularly see 100% CPU usage.

    Is this worth the upgrade long term?
    0
  • Aspiring techie
    I'm waiting to see what happens when AMD releases Ryzen on a better process. Maybe Intel's clock speed advantage will be shrunk.
    3
  • saunupe1911
    Anonymous said:
    @LilDog1291:
    A delidded i7-8700K is around 15-20 degrees cooler. The problem isn't the architecture, but the TIM instead of solder.


    90% of consumers aren't purchasing delidded processors. Only extreme enthusiasts.
    7
  • Aspiring techie
    I find it interesting that an 8-core, overclocked Ryzen 7 1800X is using less power than a stock i7 8700K.

    Also, it would be interesting to compare a Kaby Lake i7 vs a Coffee Lake i5 at the same clock rates. Does a 4 core 8 thread CPU beat a 6 core 6 thread CPU?
    6
  • dstarr3
    Well, AMD didn't wear that crown for very long. But thanks to them for shaking up the market!
    0