It feels like forever now, but there was a time when you could buy a reasonably affordable Intel processor like the Core i5-750 and clock out the snot to get the performance of the Core i7 level. That was in 2009 and it was the last time you could overclock a non-K Intel processor or a Core i3 processor of any specification (until now, but stick to us).
In 2011 Sandy Bridge stormed onto the stage and meant the death of CPU overclocking as we knew it. If you wanted to overclock a Core i5 processor, you had to buy the 2500K for $ 216, which was a little more expensive than the corresponding non-K model (around $ 12 at the time) and a little over 20% more expensive than that cheapest Sandy Bridge Core i5.
Even Core i7 processors suffered the same fate. Sandy Bridge was only available in two variants: a locked 2600 for $ 294 or an unlocked 2600,000 for $ 317. Both ran at 3.4 GHz, but the unlocked model could easily be brought up to 4.5 GHz, which corresponds to an effortless frequency increase of 32%.
On the other hand, the truly affordable Sandy Bridge Core i3 models ($ 117 to $ 138) have never received an unlocked K model, and this goes from the core version of the second generation to the current series of the sixth generation.
There are many reasons why people overclocked earlier, some did to tinker with the hardware, but most, including me, did to a flagship level or even higher performance with a significantly cheaper processor to reach. For five years, Intel has been able to stop this to a certain extent and, with the exception of the Pentium G3258 Anniversary Edition, only limit it to the most expensive CPUs.
As good as the Pentium G3258 is, its dual-core design offers limited performance even when the chip is heavily overclocked. Since then, we've been dreaming of a similar Core i3 model that supports HyperThreading and can overclock well beyond its standard operating frequency of 3.7 GHz.
Skylake started this year with the rumor of a strong overclocking of non-K processors due to an adjustable base clock, which never happened. At this point, we would even be satisfied with another unlocked Pentium that pushed the $ 64 G4400 beyond its 3.3 GHz clock speed, which would be a dream for budget builders on an equally affordable motherboard.
Now don't dream anymore! Overclocking circles continued to insist that overclocking BCLK (base clock) in Skylake processors might be an option, but it would be up to motherboard manufacturers to circumvent Intel's restrictions. Asrock contacted us last night to let us know that there is an updated BIOS that enables this condition, and we took the opportunity to test and confirm it.
Asrock has unfolded part of its magic and activated overclocking the base clock on all non-K Skylake S processors. This is, Any Asrock Z170 motherboard can overclock the Pentium G4400, G4500, G4520, Core i3-6100, i3-6300, i3-6320, Core i5-6400, i5-6500, i5-6600 and Core i7-6700 beyond their default settings .
We have learned that this updated BIOS for their Z170 motherboards will be available to owners very soon. Let us see how the Core i3-6100 develops when it is fully unleashed.
How does it work?
Non-K Skylake processors are multiplier locked, and motherboard manufacturers can't avoid this. Rather, they have found a way to enable overclocking the base clock with nothing more than a BIOS update.
This can be partly explained by the fact that, unlike their predecessors, Skylake processors do not bind the base clock frequency to other parts of the system such as the PCIe bus or the memory subsystem, which means that the base clock is extracted beyond the usual 100 MHz . t bring instability to the rest of the system.
For example, the Core i3-6100 has a base clock of 100 MHz with a 37 clock multiplier that is effective for its 3700 MHz operating frequency.
The clock multiplier remains locked in non-K processors, but you can now increase the base clock as much as your processor allows. In our previous tests with the Core i3-6100, 127 MHz was the highest stable base clock that we could achieve. Multiplied by 37, that's 1 GHz overclocking, and it's no shame.
The vcore was set to 1.350 V (CPUz reported 1.360 V) and the DDR4-3000 memory was satisfied with the 3048 MHz setting.
With the Asrock BCLK (Base Clock) unlock method, you need to disable the iGPU. The integrated HD Graphics 530 has been deactivated on our Core i3-6100. We do not suspect that many overclockers who are trying to get the best out of their system want to use integrated graphics anyway, i.e. a discrete graphics card.
As in the old days of front-side bus (FSB) overclocking, we find that increasing the base clock dramatically improves memory bandwidth performance. Although the DDR4 memory is still operated at 3 GHz, it can now reach 35.6 GB / s, which corresponds to a significant increase in memory performance by 18%. It's quite a sight to see a Core i3 processor that delivers well over 30 GB / s.
Here we see a massive 24% increase in multithread performance in Cinebench and a 25% increase in single thread performance measurement. At 4.7 GHz, this makes the Core i3-6100 faster than the Core i5-4430, even if all four cores are fully utilized. In addition, the 6100 was able to reach the FX-8320E and destroy it when measuring single-thread performance, even if the FX processor was clocked at 4.6 GHz!