When Intel launched its new high-end desktop platform a few weeks ago, we were provided with Core-X CPUs from quad cores on the latest Kaby Lake microarchitecture, and 6/8/10 core parts on the Skylake-SP microarchitecture derived from the enterprise line and taking a different route to how the cache was structured over Skylake-S. At the time we were told that these latter parts would be joined by bigger SKUs all the way up to 18 cores, and up to $2000. Aside from core-counts and price, Intel was tight lipped on the CPU specifications until today.

Skylake-X goes HCC

The original Skylake-X processors up to 10 cores used Intel’s LCC silicon, one of the three silicon designs typically employed in the enterprise space, and the lowest core count. The other two silicon designs, HCC and XCC, have historically been reserved for server CPUs and big money – if you wanted all the cores, you had to pay for them. So the fact that Intel is introducing HCC silicon into the consumer desktop market is a change in strategy, which many analysts say is due to AMD’s decision to bring their 16-core silicon into the market.

Both the new HCC-based processors and the recently released LCC-based processors will share the same LGA2066 socket as used on X299 motherboards, and all the processors will differ in core count, with slight variations on core frequencies, TDP and price.

The Skylake-X line-up now looks like:

Skylake-X Processors
  7800X 7820X 7900X   7920X 7940X 7960X 7980XE
Silicon LCC   HCC
Cores / Threads 6/12 8/16 10/20   12/24 14/28 16/32 18/36
Base Clock / GHz 3.5 3.6 3.3   2.9 3.1 2.8 2.6
Turbo Clock / GHz 4.0 4.3 4.3   4.3 4.3 4.3 4.2
TurboMax Clock N/A 4.5 4.5   4.4 4.4 4.4 4.4
L3 1.375 MB/core   1.375 MB/core
PCIe Lanes 28 44   44
Memory Channels 4   4
Memory Freq DDR4 2400 2666   2666
TDP 140W   140W 165W
Price $389 $599 $999   $1199 $1399 $1699 $1999

Along with this, we have several release dates to mention.

  • The 12-core Core i9-7920X will be available from August 28th
  • The 14-18 core parts will be available from September 25th (my birthday…)

On the specification side, the higher-end CPUs get a kick up in TDP to 165W to account for more cores and the frequency that these CPUs are running at. The top Core i9-7980XE SKU will have a base frequency of 2.6 GHz but a turbo of 4.2 GHz, and a Favored Core of 4.4 GHz. The turbo will be limited to 2 cores of load, however Intel has not listed the ‘all-core turbo’ frequencies which are often above the base frequencies, nor the AVX frequencies here. It will be interesting to see how much power the top SKU will draw.

One question over the launch of these SKUs was regarding how much they would impinge into Intel’s Xeon line of processors. We had already earmarked the Xeon Gold 6154/6150 as possible contenders for the high-end CPU, and taking the price out of the comparison, they can be quite evenly matched (the Xeons have a lower turbo, but higher base frequency). The Xeons also come with multi-socket support and more DRAM channels, at +60% the cost.

Comparing against AMD’s Threadripper gives the following:

Features Intel Core
Intel Core
AMD Ryzen
Threadripper 1950X
Platform X299 X299 X399
Socket LGA2066 LGA2066 TR4
Cores/Threads 18 / 36 16 / 32 16 / 32
Base/Turbo 2.6 / 4.2 / 4.4 2.8 / 4.2 / 4.4 3.4 / 4.0
GPU PCIe 3.0 44 44 60
L2 Cache 1 MB/core 1 MB/core 512 KB/core
L3 Cache 24.75 MB 22.00 MB 32.00 MB
TDP 165W 165W 180W
 Price $1999 $1699 $999

We fully expect the review embargoes to be on the launch dates for each CPU. Time to start ringing around to see if my sample was lost in the post.

Related Reading

Update on 8/8:

Due to some sleuthing, PCGamer managed to obtain turbo frequencies based on per-core loading. I'm surprised Intel doesn't give this data out like candy when the products are announced, but we're glad to have it nonetheless.

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  • kjboughton - Wednesday, August 9, 2017 - link

    If the HEDT parts come off the Xeon line, they will provide for ECC.

    Support will be up to individual motherboard providers. ECC is a mainstay of the Xeon line and to the best of my knowledge no Xeon is available which does not provide for ECC memory usage.

    As the circuitry that provides for ECC is contained entirely within the IMC, chipset selection is rather inconsequential as well. X79 runs ECC just like C602; likewise, X99 runs with ECC as does C612, so long as you drop a Xeon in there (and not an i7 in the case of the consumer chipsets).

    I would bet a juicy steak that the HCC HEDT Skylake-X parts work with Unbuffered/Unregistered ECC memory quite nicely.
  • AntonErtl - Tuesday, August 8, 2017 - link

    It can actually be worse: As reported in c't 17/2017 p.98, when you run the Linpack benchmark on a Core i9-7900X on the Gigabyte X299 Aorus Gaming 3 or MSI X299 SLI Plus, it consumes a lot of power (259W CPU package power on the MSI board) all the time, but delivers only half the performance compared to the same CPU on the Asrock X299 Taichi or Asus Prime X299-A. The explanation is that the BIOSes on the Gigabyte and MSI boards let the CPU run at a high clock, and it gets so hot that thermal throttling sets in. The other boards apparently have a saner Turbo policy by default (you can also get that on the Gigabyte and MSI boards by manually adjusting the power limit with the Intel XTU.
  • nevcairiel - Tuesday, August 8, 2017 - link

    Anyone spending this kind of money on a CPU should probably take some care to properly set it up - you don't even need XTU for that, the relevant settings are available in the BIOS as well.

    Defaults greatly differ between boards, that is true.
  • Gothmoth - Tuesday, August 8, 2017 - link

    @nevcairiel .... what a complete BS.

    people who are using these kind of cpus are often artist and other professionals who are not computer nerds. a computeer should run fine with default settings. the need to "properly setup the bios" is something 80% of the customers will probably never do. the world is bigger than a few nerd websites.
  • nevcairiel - Tuesday, August 8, 2017 - link

    Well those people are also unlikely to self-assemble a PC, aren't they?
    Whoever does the assembly of such an expensive system should know how to set it up.

    When you buy a pre-assembled system, I would expect such a setup to have been performed indeed.
  • Ian Cutress - Wednesday, August 9, 2017 - link

    We posted about MB manufacturers doing their own thing YEARS ago. www.anandtech.com/show/6214/multicore-enhancement-the-debate-about-free-mhz
  • Gothmoth - Tuesday, August 8, 2017 - link

    what is this list at the bottom exactly?
    in the text you mention a max turbo of 4.4 for the 18 core.... in the list the max turbo is 4.2 GHz.
  • Elsote - Tuesday, August 8, 2017 - link

    In the table there is a "turbo clock (4.2)" and a "turbo max clock(4.4)"
  • Ian Cutress - Wednesday, August 9, 2017 - link

    TB2 is 4.2 GHz
    TB3 (favored core) is 4.4 GHz, requires OS software.
  • azazel1024 - Tuesday, August 8, 2017 - link

    I find it interesting that Intel is making this move. I mean, it makes sense for them too.

    On the other hand, looking at the charts, the $999 part for Intel gets you 10 cores, 20 threads, 3.3GHz base, 4.3GHz turbo and 40 PCI-e lanes. The $999 part for AMD gets you 60% more cores and threads (16/32), 3.4GHz base, 4GHz turbo and 60 PCI-e lanes.

    I am sure the Intel part will be better in single thread, but it looks like the AMD part likely promises to crush the same price Intel part in most all multithreaded workloads.

    Which is nice. For the last few years the number of workloads where you could say Intel was the price-performance leader were very, very, very tiny. Now it looks like AMD really does promise to be the price-performance leader, and in some cases outright performance leader in a number of categories.

    If I had the spare change for an upgrade I'd definitely be looking at the "low end" Ryzen 8/16 part as an upgrade of my Ivy Bridge quad core desktop. Then again, maybe next year AMD will have something even better in the offing.

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