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Intel Core i7-7820X Skylake-X Review

Our Verdict

The Skylake-X-based Core i7-7820X offers strong multi-threaded performance and a lower price point than Intel's Broadwell-E equivalent. But we did experience some performance regression in a few game titles and applications. Core i7-7820X delivers the highest possible multi-threaded performance from an eight-core processor, provided the application can utilize its resources effectively.

For

  • Strong multi-threaded performance
  • Workstation and productivity applications

Against

  • Performance regression in some games and applications
  • Price
  • Power consumption
  • Thermal paste

Features & Specifications

What we've seen of Intel's newest HEDT platform so far hasn't inspired much excitement. First, there were complaints of high temperatures and limited overclocking, addressed in The Skylake-X Mess Explored: Thermal Paste And Runaway Power. Then we collectively scratched our heads, wondering what the company was thinking in our Intel Core i7-7740X Kaby Lake-X Review.

But there are plenty of options between the quad-core Core i5 and Intel's 36-thread Core i9 flagship. In fact, the X-series includes nine models this time around, more than any other HEDT family to date. And it's the mid-range Core i7s that we expect to be most popular due to their tamer price points.

In yet another sign of a renewed fighting spirit, Intel's $600 Core i7-7820X slots in below the $1000 Core i9-7900X. That big $400 step down from the 10-core model is uncharacteristic for Intel. Its older eight-core Core i7-6900K bore a shocking $1100 price tag. No doubt, Intel is looking to stave off AMD's Ryzen 7 models. While the $500 "savings" versus its previous generation is certainly nice, however, Intel continues to struggle against AMD's disruptive pricing scheme and looser approach to segmentation. 

The Core i7-7820X has eight Hyper-Threaded cores, so comparisons to AMD's Ryzen 7 models are inevitable. The $600 -7820X does battle against the $500 Ryzen 7 1800X. And as a result of unlocked multipliers up and down AMD's portfolio, even the $330 Ryzen 7 1700 is a viable competitor. Intel continues to enjoy an advantage in most lightly-threaded workloads, but the company just can't match Ryzen 7's value, particularly in workloads able to exercise all eight cores. It also helps that AM4-based motherboards are a lot less expensive.

Of course, Core i7-7820X drops into an LGA 2066 interface on motherboards with the X299 "Basin Falls" platform controller hub. We already discussed how processor choice can severely limit this chipset's connectivity in our Core i7-7740X review. And fortunately, Core i7-7820X doesn't suffer nearly as much as Kaby Lake-X. However, you do have to tolerate a "mere" 28 lanes of PCIe 3.0. Last generation, Core i7-6850K in roughly the same price range gave you 40 lanes, so we consider the drop to 28 a regression. Granted, AMD only exposes 16 lanes with Ryzen 7, so Intel does end the PCIe comparison ahead.

Core i7-7820X features a 3.6 GHz base clock that boosts up to 4.3 GHz across two cores in lightly threaded workloads. That's a marked increase over what the Broadwell-E-based Core i7-6900K could do. Further, -7820X supports Turbo Boost Max Technology 3.0, which can push the CPU's two "best" cores up to 4.5 GHz using a piece of installed software. In theory, that should allow Skylake-X to dominate single- and multi-threaded benchmarks alike.

Intel also officially supports up to DDR4-2666 across the -7820X's quad-channel memory controller. Compared to Ryzen 7's dual-channel design, Skylake-X can theoretically move a lot more data, which is useful in certain prosumer applications.

Similar to the Core i9-7900X we already reviewed, -7820X is rated for up to 140W. If you're curious about what that number means to power consumption, heat, and overclocking headroom, check out the aforementioned deep-dive (The Skylake-X Mess Explored: Thermal Paste And Runaway Power) for more.

And if you'd like some more background on Intel's 14nm Skylake-X architecture, we'd encourage you to read through Intel Core i9-7900X Review: Meet Skylake-X, where we introduce the new mesh topology, cache hierarchy (-7820X boasts 8MB of L2 and 11MB of L3), and fresh ISA extensions (unfortunately, -7820X loses one AVX-512-capable unit per core compared to -7900X). 

Speed Shift, which allows the processor to handle power-state transitions autonomously, also makes its debut on the high-end desktop. The tactic eliminates latent operating system commands and provides faster resumption times from lower power states. That equates to a snappier experience. Intel also includes support for the vROC (Virtual RAID on CPU) feature that allows you to coalesce up to 20 SSDs into a single bootable volume, though you'll have to buy an upgrade key to unlock it. Intel remains curiously silent on pricing, and keys aren't available yet.


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  • cknobman
    Just want to say the Ryzen 7 1800x isnt $500 anymore and has not been for weeks now.

    The processor is selling for $420 or less. Heck I bought mine yesterday from Fry's for $393
    Reply
  • artk2219
    19984543 said:
    Just want to say the Ryzen 7 1800x isnt $500 anymore and has not been for weeks now.

    The processor is selling for $420 or less. Heck I bought mine yesterday from Fry's for $393

    Not to mention the fact that you can find the 1700 for even less, and more than likely be able to bump the clocks to atleast match the 1800x. Microcenter was selling them for 269.99 last week.
    Reply
  • Ne0Wolf7
    At least they've done something, but it still too expensive to sway me.
    Perhaps full blown profesionals who need something a bit better than what Ryzen has right now but can go for an i9 would appreciate this, but even hen he/she/it would probably wait to see what threadripper had to offer.
    Reply
  • Scorpionking20
    So many years past, I can't wrap my head around this. Competition in the CPU space? WTH is this?
    Reply
  • Houston_83
    I think the article has some incorrect information on the first page.

    "However, you do have to tolerate a "mere" 28 lanes of PCIe 3.0. Last generation, Core i7-6850K in roughly the same price range gave you 40 lanes, so we consider the drop to 28 a regression. Granted, AMD only exposes 16 lanes with Ryzen 7, so Intel does end the PCIe comparison ahead."

    Doesn't Ryzen have 24 lanes? Still under intel but I'm pretty sure there's more than 16 lanes.
    Reply
  • artk2219
    19984718 said:
    I think the article has some incorrect information on the first page.

    "However, you do have to tolerate a "mere" 28 lanes of PCIe 3.0. Last generation, Core i7-6850K in roughly the same price range gave you 40 lanes, so we consider the drop to 28 a regression. Granted, AMD only exposes 16 lanes with Ryzen 7, so Intel does end the PCIe comparison ahead."

    Doesn't Ryzen have 24 lanes? Still under intel but I'm pretty sure there's more than 16 lanes.

    Ryzen does have 24 lanes, but only 16 are usable, 8 are dedicated to chipset and storage needs.
    Reply
  • JimmiG
    19984740 said:
    19984718 said:
    I think the article has some incorrect information on the first page.

    "However, you do have to tolerate a "mere" 28 lanes of PCIe 3.0. Last generation, Core i7-6850K in roughly the same price range gave you 40 lanes, so we consider the drop to 28 a regression. Granted, AMD only exposes 16 lanes with Ryzen 7, so Intel does end the PCIe comparison ahead."

    Doesn't Ryzen have 24 lanes? Still under intel but I'm pretty sure there's more than 16 lanes.

    It does, but only 16 are usable, 8 are used for chipset and storage needs.

    16X are available for graphics as 1x16 or 2x8.
    4X dedicated for M.2
    4X for the chipset that's split into 8x PCI-E v2 by the X370 and allocated dynamically IIRC
    Reply
  • Zifm0nster
    Would love to give this a chip a spin.... but availability has been zero.... even a month after release.

    I actually do have work application which can utilize the multi-core.
    Reply
  • Math Geek
    does look like intel was caught off guard by amd this time around.

    will take em a couple quarters to figure out what to do. but i'm loving the price/performance amd has brought to the table and know intel will have no choice but to cut prices.

    this is always good for the buyers :D
    Reply
  • Amdlova
    Why we have overclocked cpus ons bench but dont have power compsumation! this review is biased to intel again !? are tomshardware fake news ?
    Reply