The latest i7-68xx and i7-69xx Broadwell E processors come with a new feature called Intel® Turbo Boost Max Technology 3.0 which, in short, adds an extra punch to the maximum supported turbo frequency. And I don’t know why, but data and reviews (at that time) over at sites like wccftech.com, tomshardware.com and anandtech.com do show the wrong data, because this is what is should have been:
i7-6950X (10 Cores / 20 Threads)
Base Frequency 3000 MHz, Max Turbo Frequency 3500 MHz / 4000 MHz.
i7-6900K (8 Cores / 16 Threads)
Base Frequency 3200 MHz, Max Turbo Frequency 3700 MHz / 4000 MHz.
i7-6850K (6 Cores / 12 Threads)
Base Frequency 3600 MHz, Max Turbo Frequency 3800 MHz / 4000 MHz.
i7-6800K (6 Cores / 12 Threads)
Base Frequency 3400 MHz, Max Turbo Frequency 3600 MHz / 3800 MHz.
This (updated) data comes straight from Intel, but it wasn’t so helpful with other people – like anandtech – when they asked about this new feature. See also: ‘Intel refuses to state the effect of TBM3, saying that each CPU is different and could boost by different amounts‘. But now you know (a pretty good review by all means otherwise).
In other words. With Intel® Turbo Boost Max Technology 3.0 enabled in the BIOS both the i7-68n0K processors get two extra Turbo bins (200 MHz), the i7-6900K three (300 MHz) and the i7-6950X (extreme edition) five (500 MHz). See values in red (the ‘suggested’ 4000 MHz in the MSI BIOS is correct). The blue values are the frequencies for Turbo Boost Technology v2.0.
So now we have two different Turbo frequencies, and benchmarks and applications will run faster if only one core is active. Making it much more responsive and boot faster on OS X. Like increasing the single-core multiplier in the BIOS with the previous generation of HEDT processors, but this can potentially become a great feature… when all BIOS versions and drivers (for Linux and OS X) do what they are supposed to do. That however is unfortunately not yet the case (see anandtech.com review about the default settings in the BIOS).
And as you might have guessed… the ssdtPRGen.sh Broadwell Data.cfg already supports it. And for any other OC you can to use:
./ssdtPRGen.sh -turbo [max turbo frequency]
Update: Intel® Turbo Boost Max Technology 3.0 is a Windows specific feature, since Intel said that it has no plans to add support for Linux, let alone OS X, and they use a software driver to read/write the following MSRs:
0x194 / MSR_MCG_R12
0x8B / IA32_BIOS_SIGN_ID
0x1A0 / IA32_MISC_ENABLE
0x35 / MSR_CORE_THREAD_COUNT
0xE7 / IA32_MPERF
0xE8 / IA32_APERF
The first MSR (0x150) is also the most important one since this MSR is used to change the Fully Integrated Voltage Regulator settings, but at the time of this writing, there is no (public) documentation available. That is unfortunately for us, but this only means that we will have to do a little extra work, like disassembling the Windows driver and read the MSRs to see what the driver really does 😉