Intel Core i7-7740X Kaby Lake-X Review

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Project CARS & Rise of the Tomb Raider

Project CARS

We spot a bit more variation between the stock Core i7s, perhaps suggesting some sensitivity to memory frequency. Project CARS scales very well with increased host processing resources, so the brawny Core i9-7900X unperforms our expectations. Again, the -7740X's gain over the -7700K from overclocking is a mere 1.4%.

Rise of the Tomb Raider

Rise of the Tomb Raider recently received a patch that significantly improves Ryzen's DX12 performance, making this one more title optimized for AMD's latest platform. We're still sticking to DX11-based testing, though, to keep the playing field as level as possible.

A stock Core i7-7740X loses by 1.3% to the -7700K, but a bit of overclocking turns the tables by 1%. That certainly isn't worth the X299's price premium.

We clearly see the delta between AMD's Ryzen and Intel's Core processors grow at the test sequence's tail end, where it becomes more CPU-intensive. Core i7-7740X encounters a notable frame time outlier towards the end of the test. Meanwhile, the Ryzen 5 1600X briefly spends time under the 90 FPS mark.


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Paul Alcorn
Managing Editor: News and Emerging Tech

Paul Alcorn is the Managing Editor: News and Emerging Tech for Tom's Hardware US. He also writes news and reviews on CPUs, storage, and enterprise hardware.

  • AgentLozen
    I'm glad that the option for Kaby Lake is available on the x299 chipset. In practice it seems impractical. This article shows you have to pay a lot more for slightly higher overclocking potential.

    I'm curious what Intel's plans are for next year regarding their high end desktop chips. They've already used the Kaby Lake X name for this generation. Should we expect Kaby Lake X 8900X?
    Reply
  • Kaz_2_
    Intel high power consumption is not great in thr long run. You want the best for your investment
    Reply
  • TJ Hooker
    The curve below shows clearly that waste heat isn't dissipated quickly enough. Just as we did in our AMD Ryzen and Intel Core i9 launch articles, we used a very thin copper plate to measure the heat spreader's temperatures as well.
    Why aren't there any numbers/divisions on the horizontal axis? Also, you say you did the same thing for the Ryzen reviews but I didn't see a similar graph in those articles (might just be blind though).
    Reply
  • Roland Of Gilead
    in the HPC graph, you have two 'Ryzen 7 1600x' s.....
    Reply
  • Roland Of Gilead
    power consumption gaming loop - I5 7600x?
    Reply
  • the nerd 389
    How does the thermal performance of this chip compare to the 7700k? Specifically, does the larger surface area of the heat spreader give you a meaningful increase in thermal conductivity between the die and the heatsink?
    Reply
  • rantoc
    Dang intel seem to be doing yet another stupid move with X299 beside rushing it out the door making the AMD's pretty brand new architecture/platform appear mature in comparison. As for this move - What's the incentive to pay premium for the X299 when getting a chip like this that won't even utilize it fully? The 7700k and platform are equal in performance in most tests and far cheaper...

    With the poor thermal transfer between the core and heat-spreader the retail chips won't likely even overclock well either. Never cared about the cherry picked "reviews" chips at all when it comes to overclocking as they very rarely represent the retail chips.
    Reply
  • rantoc
    What's the incentive to buy an expensive motherboard and yet get near zero of it's true potential with this cpu? That's paying for a lot of real estate that can't be used at all and on top of that the same poor thermal transfer between the core and heat-spreader meaning a good stable oc is harder to obtain and far less likely to happen on the retail IE non-review cherry picked ones.

    I think intel shoot themselves in the foot by scaling this one down to much and then couple it with an overpriced platform for what you get out of it, x299 will be good no doubt but only with the right chips and only when the rushed out of door bugs been fixed.
    Reply
  • This is awesome setup because you can buy x299 motherboard for $219 dollars already which gives you amazing room for later upgrade and this CPU can run 5.0Ghz easily producing very little heat. People at Toms Hardware completely missed the point. I'd rather get $219 x299 motherboard than outdated Z270 for $160.
    Reply
  • And as for heat...i think heat talk i have been reading lately is just BS.
    Reply