Intel Skylake i7-6700K overclocking test

Due to various reasons, Intel's recent generations of processors have very limited overclocking. Only the K series black box version can adjust the multiplier, and the external frequency is basically in a dead end state, with only a limited number of levels to choose from.

The reason given by Intel is that Turbo Boost is very smart and will automatically exceed the limit, so there is no need to fiddle with it. However, it is too depressing for players who like to squeeze every bit of value.

Skylake finally complied with public opinion and completely opened up overclocking (of course, it is still only limited to the K black box version). While enhancing the frequency multiplier, the external frequency also supports fine adjustment of each MHz, ranging from 100-300MHz. At the same time, memory overclocking has also been greatly improved, and the adjustment range has been reduced to 100/133MHz.

On some advanced motherboards, the external frequency can even reach up to 650MHz, and supports ultra-fine adjustment in steps of 0.0625MHz.

This is largely thanks to the integration of Haswell/Broadwell. The recent voltage control module has been returned to the motherboard, which allows motherboard manufacturers to continue to play a role in power supply while reducing the complexity of the processor itself, including overclocking, power supply, heat dissipation and other aspects. However, it is rumored that it will be integrated again in the next generation, which is really troublesome.

This is the overclocking architecture diagram of the Skylake platform. As you can see, there are three main input voltages for the processor, namely core voltage (VCORE), memory/controller voltage (VSA), and core graphics voltage (VGT). The PCI-E/DMI control module is also kept independent from other parts through domain isolation (asynchronous clock demarcation line), which does not affect overclocking.

The core and ring bus multiplier can be up to 83, the core graphics multiplier can be up to 60, the core graphics cache multiplier can be up to 40, the DDR4 memory multiplier can be up to 24@133MHz or [email protected] should be enough.

Since the second-generation Sandy Bridge Core, overclocking capabilities have been steadily declining year by year, with each generation losing 200MHz. This has also made many users sigh that the i7-2700K 4.7GHz can last for another N years.

The alternative Devil's Canyon i7-4790K and i5-4690K in the Haswell family have made some improvements in overclocking and better control of temperature. In addition, their own frequencies are relatively high, so they are still worthy of recognition. Can Skylake be better than it?

Without further ado, let's take a look at the test conducted by AnandTech using four i7-6700Ks, including three samples and one retail version. The main motherboard used was MSI's Z170A Gaming M7, and two other motherboards from MSI and ASUS were used for confirmation.

In this test, only the multiplier is adjusted, and the external frequency will be tested later.

One of the samples stably exceeded 4.7GHz at a voltage of 1.4V, and the other two exceeded 4.6GHz at around 1.4V.

The retail version is the worst, with a maximum of 1.275V 4.5GHz, and it will automatically downclock at 1.4V 4.6GHz.

After repeated tests, it was found that 4.6GHz is basically the stable overclocking limit of the i7-6700K, and the phenomenon that the retail version is not as good as the engineering sample was repeated.

Other media have also conducted some experiments, most of which were in the 4.6-4.7GHz range, and very few could reach 4.8GHz.

TechPowerUp was the most powerful, achieving 1.44V 5.0GHz, and at least entering the Windows system, but it was prompted that the voltage was too high, and it was not disclosed whether it could pass the test or even the stress test.

Overclocking tips:

1. When applying silicone grease, do not apply it all over. The core of Skylake is long and narrow, so it is best to apply a line from top to bottom in the center of the processor surface, and apply a little in the lower left corner. Doing so can directly reduce the load temperature by 10-15℃!

2. Skylake is more sensitive to heat than voltage. In a large number of tests, the frequency and voltage are reduced when the temperature reaches a certain level, so heat dissipation is very important, and water cooling is best.

3. The heat dissipation material between the processor cover and the core is still ordinary silicone grease, not advanced brazing, which greatly restricts heat dissipation and overclocking. However , it is very risky to open the cover of this generation, mainly because the substrate is too thin. Those who are not afraid of death can try it.

Oh, and let's look at the load power consumption. The i5-6600K is pretty good, with the lowest power consumption of only 63W among the flagship and sub-flagship generations, while the i7-6700K has a maximum power consumption of 110W, which is basically the same as the i7-4790K, but the thermal design power consumption is 7W higher than the latter. (The i7-6700K/i5-6600K are actually both 95W)

As for the overclocking effect of the external frequency, please stay tuned!

UPDATE——

Someone has already overclocked the i5-6600K to 552.27MHz!

As a winner of Toutiao's Qingyun Plan and Baijiahao's Bai+ Plan, the 2019 Baidu Digital Author of the Year, the Baijiahao's Most Popular Author in the Technology Field, the 2019 Sogou Technology and Culture Author, and the 2021 Baijiahao Quarterly Influential Creator, he has won many awards, including the 2013 Sohu Best Industry Media Person, the 2015 China New Media Entrepreneurship Competition Beijing Third Place, the 2015 Guangmang Experience Award, the 2015 China New Media Entrepreneurship Competition Finals Third Place, and the 2018 Baidu Dynamic Annual Powerful Celebrity.