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Intel Core i9-7900X Review: Meet Skylake-X

The X299 Basin Falls Chipset & Test Setup

The Basin Falls X299 Chipset

The Kaby Lake-X and Skylake-X processors drop into an LGA 2066 interface, supported by Intel's X299 chipset. Curiously, the platform controller hub isn't repurposed from Intel's server portfolio this time around. The 14nm, 6W piece of core logic features a four-lane DMI 3.0 connection, which is similar to a PCIe link between the processor and chipset. That's a nice doubling of throughput compared to X99's 2 GB/s DMI 2.0.

Basin Falls, Intel's code-name for X299, supports 30 HSIO (High Speed I/O) lanes that vendors can carve up into eight SATA 3.0 and 10 USB 3.0 ports, but lacks native Thunderbolt 3 and USB 3.1 Gen 2 support. Intel plans to add support in future chipsets, naturally.

X299 supports up to three RST PCIe 3.0 x4 storage devices, though the reduced PCIe lane allocations on many Skylake-X SKUs will limit connectivity options. Intel's I218 Jacksonville LAN PHY and Optane Memory support also make an appearance, but most HEDT systems will likely have an SSD. That’s a better option than Optane Memory, which merely serves as a cache for an HDD.

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Although LGA 2066 incorporates more pins than LGA 2011v3, it shares many of the same dimensions. As a result, it's physically compatible with existing LGA 2011v3 coolers. However, Intel recommends water cooling as a minimum requirement due to  Skylake-X's TDP rating. Skylake-X processors also have an integrated voltage regulator (IVR) that is similar to the FIVR implementation on Broadwell-E parts.

Like all of Intel's unlocked SKUs, the Core i9-7900X doesn't come with a bundled cooler. The company does sell its $85-$100 Liquid Cooling TS13X as an option, but as we'll discuss shortly, invest in a beefy custom loop if your plans for Skylake-X include overclocking.

Test Systems

X299-based motherboard firmware is evolving rapidly, right up through Skylake-X's launch. Reports indicate spotty Turbo Boost Max 3.0 support, which could lead to dissimilar test results from one review to the next. We tested our MSI X299 Gaming Pro Carbon AC extensively and found that it implements Turbo Boost correctly. We also disabled the all-core Turbo Boost feature to ensure a level playing field.

There were several demonstrations of memory overclocking beyond DDR4-4000 with Skylake-X processors at Computex, but we settled on DDR4-3200 to match the memory data transfer rates of our Ryzen models.

We introduced our new test system and methodology in How We Test Graphics Cards. If you'd like more detail about our general approach, check that piece out.

The only updated components in our German lab are the CPU, system memory, motherboard, and new cooling solution, so we'll just provide a quick overview in the following table:

Test Equipment and Environment
SystemGermany Intel LGA 2066Intel Core i9-7900XMSI X299 Gaming Pro Carbon AC4x 4GB G.Skill Ripjaws 4 DDR4-2600AMD Socket AM4 WorkstationAMD Ryzen 7 1800X, 1700X, 1600XAsus X370 Crosshair Hero VI2x 8GB G.Skill Ripjaws V DDR4-3200Intel LGA 2011v3Intel Core i7-6900K, Core i7-6950XMSI X99S XPower Gaming Titanium4x 4GB Crucial Ballistix DDR4-2400Intel LGA 1151Intel Core i7-7700KMSI Z270 Gaming 72x 8GB Corsair Vengeance DDR4-3200 @2400 MT/sAll SystemsGeForce GTX 1080 Founders EditionNvidia Quadro P6000 (Workstation)1x 1TB Toshiba OCZ RD400 (M.2, System)2x 960GB Toshiba OCZ TR150 (Storage, Images)Be Quiet Dark Power Pro 11, 850W Power Supply Unit (PSU)Windows 10 Pro (All Updates)Be Quiet Dark Power Pro 11, 850W Power Supply Unit (PSU)Windows 10 Pro (Creators Update)USIntel LGA 2066Intel Core i9-7900XMSI X299 Gaming Pro Carbon AC4x 8GB Corsair Vengeance DDR4-2666 @ 2666 and 3200 MT/sIntel LGA 2011v3Intel Core i7-6900K, Core i7-6950XASRock X99 Extreme44x 8GB Corsair Vengeance DDR4-2666 @ 2666 and 3200 MT/sAMD Socket AM4 Workstation AMD Ryzen 7 1800X, 5 1600XMSI X370 Xpower Gaming Titanium 2x G.Skill FlareX DDR4-3200 @ 2666 (stock), and 3200 MT/s Intel LGA 1151 Intel Core i5-7600K, i7-7500 MSI Z270 Gaming M7 2x G.Skill FlareX DDR4-3200 @ 2400 All EVGA GeForce GTX 1080 FE 1TB Samsung PM863 SilverStone ST1500, 1500W Windows 10 Creators Update Version 1703
CoolingGermanyAlphacool Eiszeit 2000 ChillerAlphacool Eisblock XPXThermal Grizzly Kryonaut (For Cooler Switch)USCorsair H115iCorsair H100i v2Arctic MX4
Power Consumption MeasurementContact-free DC Measurement at PCIe Slot (Using a Riser Card) Contact-free DC Measurement at External Auxiliary Power Supply Cable Direct Voltage Measurement at Power Supply 2x Rohde & Schwarz HMO 3054, 500MHz Digital Multi-Channel Oscilloscope with Storage Function4x Rohde & Schwarz HZO50 Current Probe (1mA - 30A, 100kHz, DC) 4x Rohde & Schwarz HZ355 (10:1 Probes, 500MHz) 1x Rohde & Schwarz HMC 8012 Digital Multimeter with Storage Function
Thermal Measurement1x Optris PI640 80Hz Infrared Camera + PI Connect Real-Time Infrared Monitoring and Recording


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  • Pros: 10/20 cost now $999
    Cons: Everything else

    My biggest problem with this Intel lineup is that if you want 44 PCIe you have to pay $999. No, thanks. My money goes to AMD ThreadRipper.

    Good review!
    Reply
  • rantoc
    Doubt many who purchase such high end cpu for gaming runs at a low full hd 1080p resolution, i know its more cpu taxing to run lower res at higher fps but that's for the sake of benchmarking the cpu itself.

    I would like to see 1440p + 2160p resolutions on a suitable high end card (1080ti or equalent) benchmarked with the cpu as well as it would represent real scenarios for the peeps considering such cpu.

    Thanks for a good review!
    Reply
  • James Mason
    So it seems like de-lidding the x299 processors is gonna be a standard thing now to replace the TIM?
    Reply
  • elbert
    Meet netburst 2.0 that not only can hit 100c at only (4.7Ghz)1.2v on good water cooler but only barely beats a 7700k not overclocked in games. All this is yours for the low low price of 3X. Its slower than the old 6950x in a few tests with was odd.
    Reply
  • prophet001
    There's obviously a problem if the delta is that high.
    Reply
  • James Mason
    19835717 said:
    Doubt many who purchase such high end cpu for gaming runs at a low full hd 1080p resolution, i know its more cpu taxing to run lower res at higher fps but that's for the sake of benchmarking the cpu itself.

    I would like to see 1440p + 2160p resolutions on a suitable high end card (1080ti or equalent) benchmarked with the cpu as well as it would represent real scenarios for the peeps considering such cpu.

    Thanks for a good review!
    The differences would be less noticeable at higher res than 1080p, so.... you'd just see less dissimilar numbers.
    Reply
  • Dawg__Cester
    Hmmmmm. I bought a Ryzen 1700, a water cooler, Asrock B350 MB, 16gb ram 3200Mhz for $590 plus tax. I live in New Jersey. I was very nervous about making the purchase as I knew this was coming out this week but the sale prices got me. Unless you all think I got ripped off, (DON'T TELL ME). But in all honesty I have not regretted the purchase one bit!! I even managed to save enough to get a GTX 1080 FE GPU. I did have a few bumps in the road getting the system stable (about 3 hours configuring after assembly) but I am VERY happy. I used Intel primarily and never really considered AMD other than for Video adapters and SSDs.
    After reading this along with other articles and YT videos, I have no regerts as I enjoy my Milky Way and play my games among other things.
    Just my experience. I am not seeking positive reinforcement nor advice.
    I just feel very satisfied that I did not wait and cough up 3oo more fore something I could have for less. I know, I know it makes no sense.
    But come on fellas, its the computer game!!
    Reply
  • James Mason
    19835862 said:
    Hmmmmm. I bought a Ryzen 1700, a water cooler, Asrock B350 MB, 16gb ram 3200Mhz for $590 plus tax. I live in New Jersey. I was very nervous about making the purchase as I knew this was coming out this week but the sale prices got me. Unless you all think I got ripped off, (DON'T TELL ME). But in all honesty I have not regretted the purchase one bit!! I even managed to save enough to get a GTX 1080 FE GPU. I did have a few bumps in the road getting the system stable (about 3 hours configuring after assembly) but I am VERY happy. I used Intel primarily and never really considered AMD other than for Video adapters and SSDs.
    After reading this along with other articles and YT videos, I have no regerts as I enjoy my Milky Way and play my games among other things.
    Just my experience. I am not seeking positive reinforcement nor advice.
    I just feel very satisfied that I did not wait and cough up 3oo more fore something I could have for less. I know, I know it makes no sense.
    But come on fellas, its the computer game!!

    PCPartPicker part list / Price breakdown by merchant
    CPU: AMD - Ryzen 7 1700 3.0GHz 8-Core Processor ($299.39 @ SuperBiiz)
    Motherboard: ASRock - AB350M Micro ATX AM4 Motherboard ($65.98 @ Newegg)
    Memory: G.Skill - Ripjaws V Series 16GB (2 x 8GB) DDR4-3200 Memory ($124.99 @ Newegg)
    Total: $490.36
    Prices include shipping, taxes, and discounts when availableGenerated by PCPartPicker 2017-06-19 10:47 EDT-0400
    Depends on which watercooler and which ram, but not really.
    Reply
  • Jakko_
    Wow, compared to the Ryzen 1800X, the Intel Core i9-7900X:

    is about 25-30% faster
    costs 105% more
    uses 35-40% more power

    Ryzen looks really good here, and together with the temperature problems, Intel seems to be in some deep shit.
    Reply
  • HardwareExtreme
    Too little, too late. Does Intel really think that just because it has "Intel" written on it that it must be worth $200-$300 than AMD?
    Reply