Add 1 GHz Tweak on non K model Skylake processors after BIOS upgrade
Good news for users with a regular Skylake (non K model) processor - these CPUs might not have an unlocked multiplier yet might become overclockable on that very same multiplier with a BIOS upgrade, thanks to BCLK tweaking.
A new BIOS update would result into a baseclock tweak that does not run into stability issues while adding up-to a 1 GHz OC. The news reached us through overclocker Dhenzjhen who reached 4955 MHz on a Core i3 6320, that was LN2 cooled though, we are not sure yet how this works out on air-cooling. He reached a 27% overclock over the regular 3.9 GHz clock frequency of such a processor. The results where achieved on a SuperMicro C7H170-M motherboard with special firmware. The overclock was achieved by raising the BCLK from 100 towards 127 which is possible after that (non-public) BIOS upgrade. Typically you'd get stranded in the 103/104 MHz blck range.
So any Core i3-61xx has a base clock of 100MHz with say a 37 clock multiplier = 3700MHz right?
Non-K Skylake processors are multiplier locked, motherboard manufacturers cannot bypass hits this. Skylake processors don't bind its base clock frequency to other parts of the system like the PCIe bus or storage IO, going beyond the usual 100MHz in base clock now won't bring instability to the rest of the system. The clock multiplier will remain locked in non-K processors, but you will be able to increase the base clock (BCLK) as far as you processor can take it. From the reports on the web roughly 127MHz is very likely the highest stable base clock you can reach. Multiplied by a multiplier of 37~40, you'll achieve a nice ~1GHz overclock on your CPU cores. It is now known that ASUS, Asrock and SuperMicro all are working on firmware updates to make this happen. Asrock by next week should post theirs online already. An increase of just the baseclock should not use much more energy either. Again, typically only the more expensive K model processors are tweakable like this. The screenshot is courtesy of Anandtech.
If the vendors push through proper working BIOSes, this'll mean a whole lot of value for money processor wise as these processors sit in the 130~170 EURO range. Mind you, the example Core i3 is a dual-core processor series though. But this trick should work on the entire processor range scaling from Core i3 to i5 to i7 non K models. Unless Intel will be preventing these BIOS updates of course.
If you have a ASRock Z170 OC Formula and a non K model CPU, you can try this out for yourself by downloading this BIOS. The guys over at overclocking.guide (screenshot are courtesy to them) just posted a preliminary test with benchmark, and it seems some processors even go much higher up-to a 170 Mhz BCLK.
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Crazy_Milojko : it's because BLCK is separate now from PCIE clock for example.
Some preliminary tests here
http://overclocking.guide/overclocking-non-k-intel-skylake-cpus-performance-tests/
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WFT, BCLK working stable up to 127MHz just via BIOS update/tweak!? I thought OC via raising BCLK was dead after LGA1366/1156 era.
Someone (read: CPU and mobo manufacturers) were obviously hiding something from us OC'ers for all these years, since LGA1155 release, to gain some extra profit on K CPU's and "real OC capable chipsets/mobos (OC via multiplier)" like P68/Z68/Z77... and later

Not quite. On previous generations they tied the BCLK to other subsystems such as the PCIe clock etc Ringbus to be correct. But this seems like a nice improvement! Budget gaming here we come! Might just upgrade the "Mac" to Skylake now and OC it a bit

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@ spajdrik & Twiddles
I know on Skylake's BCLK and PCIe are not tied same way like on previous generations of CPU's past LGA1366/1156 and up to Skylake. I just didn't expressed myself in right way on my previous post: I was suspecting that BCLK OC on previous CPU generations was somehow limited for puprose and that "BLCK-PCIe tied excuse" was just excuse to enable some extra profit both for:
a) Intel selling K CPU's and chipsets capable for multiplier change
b) mobo manufacturers selling more expencive mobos with chipsets capable for OC
...to us OC entusiasts willing to spend more money on OC capable HW.
Just remember not so long ago Non-Z OC affair about H87 and B85 chipsets who were by Intel specs "uncapable for multiplier change" and suddenly bam!, just via BIOS update some H87 and B85 mobos were capable for OC paired with K CPU's.
Just wondering how many OC features CPU/chipset and mobo manufacturers are hiding from our eyes i.e. we are now aware about just to force us entusiast to burn more money into OC capable hardware

Now... where the hell is my thinfoil hat....

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Seems like Intel is adding worth to the cheaper CPUs, and also the rich men can buy their 10 core CPUs, but more regular gamers with their i5 and i7 K processors don't get anything. No, in fact i5 K CPUs have steadily seen their default clock lag further and further behind the i7. When I built this PC, i5-3570K and i7-3770K had almost the same default (and turbo) clock, but now (with 6xxx series) there's a huge difference between them. You can really see the CPU world is all screwed when AMD can't get their stuff together. Hopefully a year from now things will be different with Zen.
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WFT, BCLK working stable up to 127MHz just via BIOS update/tweak!? I thought OC via raising BCLK was dead after LGA1366/1156 era.
Someone (read: CPU and mobo manufacturers) were obviously hiding something from us OC'ers for all these years, since LGA1155 release, to gain some extra profit on K CPU's and "real OC capable chipsets/mobos (OC via multiplier)" like P68/Z68/Z77... and later