Intel Kaby Lake Core i7-7700K Overclocking Preview

After having a few weeks to play around with Intel's new Kaby Lake architecture Core i7-7700K processors, we finally have some results that we want to discuss when it comes to overclocking and the magic 5GHz many of us are looking for, and what we think your chances are of getting there yourself.

Kaby Lake - Core i7-7700K Samples

So we have been covering Intel's new Kaby Lake processor before its launch now for several weeks. The first look was our Intel Core i7-7700K CPU Synthetic Benchmark Sneak Peek, then shortly after, our Intel Kaby Lake Core i7-7700K IPC Review was published.

Today we are going to cover overclocking the Core i7-7700K processors that we have on hand and will be keeping this short and sweet. We have held off on covering the overclocking till we got some more mature UEFI to work with.

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We have three 7700K processors on hand. All are labeled as you see above with "I7-7700K." These are not the usual engineering samples that we get from Intel for reviews, in fact, none of these CPUs were sourced from Intel and why we are not bound by Intel embargo dates. However, we have seen one instance in the past where Intel has sent out non-engineering labeled samples and that was with the 6700K review units. This is what Intel had to say about it at that time.

The engineering samples and the production/retail processors are the same silicon. It was just a matter of availability and this time it just worked out to provide retail product.

That said, we do believe that the processors we have on hand are representative of retail processors you will be able to purchase.

Kaby Lake - Core i7-7700K Overclocking

Out of our three 7700K processors, we have only been able to get one stable at 5GHz.

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The screen capture above shows our "good" 7700K finishing up a full DVD encode using the latest version of HandBrake. We have found HandBrake to be very reliable at predicting a solid stable overclock for everyday desktop enthusiast usage. We did run our 7700K through 4 hours of ASUS' RealBench as well without issue. Our other two 7700K processors were not up to this task, no matter how much voltage we threw at those. The 5GHz overclock above was achieved with setting the vCore at 1.32v in the UEFI. The vCore shown above in the Intel XTU utility is reporting the vCore incorrectly, so disregard that data. We did however verify that CPUz is reporting correctly, so rely on it for now. We used a triple radiator Koolance system and a model 370 CPU water block.

We were able to replicate these 5GHz stable overclocking results on three different Z270 chipset motherboards. We were also able to confirm that we could not get our other two 7700K processors to 5GHz on those motherboards as well. One of our other 7700K processors was however stable at 4.9HGz with the other stable at 4.8GHz. With both of these lower overclocks we were able to complete these at 1.32v and 1.30v. Even pushing these lesser processors up to 1.45v vCore would not net us stability.

Where all three of these processors did shine, was when it came to running very fast RAM speeds, just like we showed you last week.

Our Corsair Vengeance LPX 3600MHz RAM, part number, CMK32GX4M4B3600C18, with a 4 x 8GB footprint, was stable on all three processors and motherboards using the XMP settings.

So all in all, getting the 5GHz/3600MHz overclock was as easy as setting vCore statically and the XMP settings in the UEFI. We just had to have the "right" CPU to make the 5GHz happen. Playing around with all the other voltage settings in the UEFI never amounted to anything in terms of overclocking.

As a side note, one thing I did notice about these new Kaby Lake processors is how exceptional flat the heat spreader's mating surface is. This has been the same on all of our 7700K CPUs. Not that this is a huge deal, but worth noting for those of us looking to get every degree lower that we can.

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The Bottom Line

This is what we had to tell you about 7700K overclocking a couple of weeks ago.

"Bad" Kaby Lake CPUs are looking to do 4.8GHz at less than 1.3v vCore. "Good" Kaby Lake CPUs are looking to do the magical 5GHz at 1.35v or less. 5GHz looks to be where these hit the wall however. The "golden" Kaby Lake will deliver 5.1GHz, but at a high 1.37v vCore.

These statements still look to be true from our own experiences and what we are being told by others inside the industry. We were also told a few weeks ago that it looked many of the 7700K CPUs will be able to do 5GHz, but it is our best estimate currently, that I would not purchase a 7700K thinking that you will automatically get 5GHz on every processor.

I was also told an interesting nugget today that "all" the reviewers that did agree to Intel's embargo and took Intel's samples are getting 5.0GHz to 5.1GHz, which is something to think about. Right now I am hoping that is exactly what we see when it comes to retail processors, but I am not very sure of that. So as we always tell you, we all truly need to wait till we get our hands on CPUs that we have purchased in the wild before we make any decisions on just how overclockable these Kaby Lake processors really are. As usual, we will be buying a few of our own.

As usual, hit the discussion link below if you have any questions that I might be able to answer.