Intel Core i7-4790K Devil’s Canyon Processor Review

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Intel Core i7-4790K Devil’s Canyon CPU Overclocking


The Intel Core i7-4790K processor starts out life with a 4.0GHz base clock and can boost up to 4.4GHz. We heard that reaching 4.7GHz should be easy for most platforms with high-end air coolers or water cooling. For this review we wanted to see what we could hit with the Corsair H105 water cooler and we were hoping that the rumors of 5GHz Devil’s Canyon processors with water cooling would prove to be true.


We used the ASUS overclocking assistant on the Z97-A motherboard and was able to reach 4.59GHz in just a matter of seconds. The ASUS board automatically bumped up the multiplier from 44 to 45 and increased the Bus Speed from 100MHz to 102MHz as you can see in the screenshot above. It looks like we are off to a great start, but this is only 190MHz higher than the turbo clock speeds of the Core i7-4790K Devil’s Canyon processor.


We got into the ASUS Z97-A UEFI and manually did the overclock in AI Tweaker. We just cranked up the vCore and kept raising the multiplier until we got to 1.40V on the core and the system became unstable. By doing this we were able to enter Windows 8.1 and run a few benchmarks at 4.9GHz with 1.35V, but we just couldn’t get it fully stable and we didn’t want to go over 1.4V on the first few days that the 4790K was in our hands.


We ended up settling for 4.7GHz as that was the highest stable overclock that we could achieve on this processor.  We were able to do this by leaving everything in the UEFI/BIOS untouched and just raising the multiplier up from auto to 47. It appears that the ASUS Z97-A automatically increases the voltage and in this situation we were running at 1.351V on the core. This was the easiest 4.7GHz overclock that we have had on any Haswell processor!


This just happens to be the top overclock for our Core i7-4770K processor as well, so when it comes to overclocking performance the Core i7-4770K and Core i7-4790K appear to be about the same. We don’t have any retail 4790K chips to play around with though, so our opinion is based on our experience with our engineering sample.


With the Intel Core i7-4970K Devil’s Canyon processor running 4.7GHz we were able to score 946 on the CPU test in Cinebench. We got a score of 900 stock, so this is a modest 5% performance gain as we are only overclocking 300MHz as the turbo clocks on this chip are at 4.4GHz. A 300MHz clock increase from 4400MHz is a 6.4% increase, so this is about what you’d expect to see.


At 4.7 GHz we saw the temperatures hit 76C, which isn’t bad considering Haswell and Devil’s Canyon don’t start throttling till 95C. It looks like the Next-Generation Polymer Thermal Interface Material (NGPTIM) that is being used on the Intel Core i7-4790K and Core i5-4690K processors really does help out. 

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  • She-Ra

    Basically devil’s canyon has the same overclocking scaling as the ivy bridge 3770K in both the I5 and I7 processors. Two generations news with a few more bells and whistles but the same OC cap as ivy. If you consider it comes in at 4ghz but only jumps to 4.5-4.7 which is the same as the 4770K. Essentially a chip that comes mildly overclocked which can be achieved in the 4770K with the exact same OC’d results. Obviously, that is the chip because of those added bells and whistles. The 22nm process is showing that it’s dated. Intel really needs some new silicon or something so they can hit 5ghz. PC gamers need the speed. They should also add a feature that uses internal graphics in tandem with PCI Express graphics cards. It’s really a simple solution adding integrated graphics. I am not talking about quick sync. I simply give intel ideas to revive their PC gaming market.

  • klepp0906

    Clock for clock they’re the exact same chip. So unless your convinced you can get an extra few hundred MHz out of a 4790 save your money.

    For me running a delidded watercooled haSwell at 4700mhz I can’t imagine (based on all results I’ve seen thus far) being able to attain a high enough overclock to make it worthwhile.

    • CharlesAnderson

      I can – it’s better to run a stock Devil’s Canyon at 4700 MHz and keep your warranty intact.

  • Kat

    I think the Intel Deviled Egg would be a better name…

  • anon

    I’d like to see this and the 4770k compared when they’re both overclocked as high as possible. “High as possible” depends on the sample of course, but I still think it’s more useful then comparing with stock speeds, since the 4790k’s is higher but at the expense of greater power draw and heat.

    • Thomas Dameron

      except that OCing a CPU as high as possible reduces its life to a few months and doesn’t give any useful information

      • anon

        I meant as high as reasonably achievable.

      • klepp0906

        It does?

      • dj3hac

        I ran an Intel E8500 @ 3.6ghz for years no problem at all, it’s still running in a dedicated server. It’s be going 24/7 at that speed for 6 or 7 years now.

  • Steven Kean

    Tempting upgrade from a 3570K…

  • Will Beams

    What the heck? 71c under load with a Corsair H105 Closed Loop Water Cooler??? Then how hot does the bloody thing get with an after market air cooler, let alone the stock cooler? Something doesn’t seem to be right here…

    • Nathan Kirsch

      Haswell has always been regarded as a fairly hot processor, so nothing out of the ordinary there! I actually thought that was low and was extremely happy with that. I used the latest version of Intel XTU and screen shots are in the review and everything was done more than once and was consistent.

    • Vinny

      they were using the integrated graphics that why it ran hotter….if you use a dedicated card it wouldn’t run so hot then 🙂

    • name

      I have the 4790k with an h110 and mine doesn’t go over 60C on a full load.

      • klepp0906

        Load it with IBT then and not Aida or something foo foo :p

        (Assuming your overclocked)

  • Coach

    Great review. I was very curious/anxious to read this. It’s selling at $279 at MicroCenter. VERY tempting! I want to see how the Broadwell’s do, but I’m sure they’re price point will be much higher.

  • OJ

    Hopefully some of the 4790ks do manage to hit 5GHz otherwise the extra features such as the smoothing caps and the thermal interface don’t achieve much. Although the the improvements lead me to assume that some 4790k chips should be more stable when clocked over 4.5Ghz.

    • Thomas Dameron

      umm, 500 MHz a core is actually a pretty good boost, especially considering that the 4770k was pretty shaky at anything over 4.3 GHz

      • Joe Joejoe

        And compared to AMD, a 500Mhz boost is more like a 4×1.5Ghz boost, especially when it’s on 4 cores rather than 8.

    • ricksanchez1

      I was disappointed they didn’t push the chip until it burned. If they ran all their tests, and more come along in a week, a $350 chip can’t be sacrificed for the point of testing?