Overclocking Intel’s latest generation processors hasn’t been an easy affair after their move to a 14nm manufacturing node. Not only has heat buildup been a constant concern but the architecture itself has several checks and balances in place to insure temperatures and TDP remain under tight control.
Kaby Lake changes things up a bit by offering a number of new features that should help experienced overclockers achieve higher frequencies with more stability. First and foremost is the new AVX Offset Ratio which allows a user to dial down the frequency for AVX instruction sets. Since these instruction sets require more power, they can lead to instability on an otherwise perfectly stable overclock. Now when the chip detects the use of AVX it will automatically reduce its core speed so stability is maintained.
One of the main limitations of overclocking Intel’s latest processors is their stability (or lack thereof) when moving outside typical multiplier-based overclocks. Typically once the multiplier is maxed out, you would move onto BCLK but the amount of additional headroom gained through that secondary method was always tightly constrained. With Kaby Lake Intel has introduced revised voltage controls which are not only simplified but are also eminently aware of the system’s current Base Clock. Not only will this add more granularity but there’s hope BCLK overclocks will also be improved.
Intel claims these advances allow for consistently better top-end frequencies with Kaby Lake than its predecessors. However, since all of these CPUs actually start their lives off with higher clock speeds from day one, I don’t think we will see any massive improvements percentage-wise when it comes to overclocking.
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So what about our results? Well the i5-7600K really dressed to impress with 5.1GHz on all four cores while the i7-7700K hit just north of that at 5.126GHz after some additional BCLK massaging. Note that while we pumped a full 1.45V into both of these chips to find their true maximum (with a Corsair Hydro H100i GTX), they were both 5.0Ghz stable at a much more reasonable 1.35V.
In addition to that, prior to launch the motherboards we are using don’t yet have the updated BIOSes necessary to take advantage of Intel’s new BCLK-aware voltage controls. As such, the amount of secondary clock speed tuning we could achieve was limited at best.
I’d expect things to improve as time goes on and motherboard vendors and their BIOS teams learn more about these new processors and their true capabilities.
Many of you will likely read through this review and roll your eyes since with Kaby Lake, Intel isn’t breaking their cyclical (and relatively minimal) intergenerational performance improvements. Others may skip this entirely since a lot of the benchmarks have already been leaked and they’ll decide Kaby Lake isn’t for them. If you’ve managed to get this far, you may already know that I think Kaby Lake is actually an excellent refresh of Skylake. It not only adds more performance where it counts but the Z270 platform itself is a very well updated foundation upon which to build a new system.
Honestly, if you looked towards Kaby Lake to provide something different, then you haven’t been paying attention to the fact that Intel is somewhat mired in the 14nm process node and their current architecture simply needs refreshes to keep itself “interesting”. They aren’t facing any overt pressure from AMD for the time being, incremental updates like Kaby Lake are still netting them a 7-12% performance uptick every year and the Core series architecture has stood the test of time. If anything this situation should highlight Intel’s relative strengths instead of giving fodder to their naysayers.
Within this review I tested the new lineup’s two flagship chips; the 7600K and 7700K. There isn’t necessarily a “winner” per se but I feel the lower priced i5-series part provides an awesome bang-for-buck solution. It performed excessively well in gaming due to high base and Turbo frequencies, some basic overclocking saw it hit 5GHz, it is very efficient (a key point for ITX builds) and with a price that’s nearly $100 less than its big brother, some of those much-needed funds could be funneled into a higher end GPU purchase instead. If you absolutely need the multi-tasking goodness granted by an eight thread processor then the i7-7700K would be a great fit unless Broadwell-E and its i7-6900K were factored into the equation.
With that being said it is obvious that Kaby Lake isn’t for everyone. If you are sporting a Haswell or newer system there will be very few –if any- readily apparent performance benefits, especially if you want to play a wait-and-see game with Intel’s Optane. From a percentage basis, overclocking hasn’t changed that much either even though seeing 5GHz out of any processor will cause uplifted eyebrows with even the most jaded power user.
Those who still have an Ivy Bridge or earlier setup should be looking closely at Kaby Lake for a viable upgrade path, if only for the long list of key feature Z270 brings to the table over pre-Z97 chipsets. The processors themselves will naturally outperform Ivy / Sandy Bridge (more on this in an upcoming article) but even the most basic of Z207 boards will run circles around their earlier predecessors. Even pushing aside Optane compatibility, features like USB 3.1, Thunderbolt, M.2 / NVMe implementation, build-in audio support, SSD management algorithms and countless other elements allow these new motherboards to stand head and shoulders above older PCH’s.
Kaby Lake is a step in the right direction for Intel. There’s enough of a performance uplift and motherboard feature set expansion that users of much older systems should look into upgrading. Meanwhile, pricing remains stagnant and there are even a few cost reductions versus Skylake CPUs. I really can’t find anything NOT to like here and I’m sure those praises will be sung all the louder once that i3-7350K drops.
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