Intel Core i7-7820X Skylake-X Review

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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