<< Solved >> Skylake i7-6500U minimum CPU frequency

[michmill]

I have a Dell 7568 with an i7-6500U CPU. I've followed RehabMan's Native Power Management post, and everything is is almost working perfectly. The one issue is I can't get the CPU clock/frequency to drop below 1.3 GHz, even when almost nothing else is running. The Intel specs for the 6500U show a minimum frequency of 800MHz. The faster clock is draining my batter faster than it should. Is there way to lower the minimum clock speed, or implement a more aggressive power management scheme when on battery. I attached a screenshot of the IPG and a PR.zip.

 

[favoriti]

Had this issue with my laptop - easy solved I found is using CPUFriendDataProvider.kext providing the idle setting to CPUFriend.kext (add this Lilu plugins to clover/kexts/other) - with that i went from 1.3 idle to 0.9
I think CPUFriendDataProvider.kext need to be builded for your rigs - share mine for testing but probably you will need to get or build your own
Found this information here (post 2917 and after):

[Guide] Dell XPS 13 9360 on MacOS Sierra 10.12.x - LTS (Long-Term Support) Guide

I tried the CPUFriend posted by @zanzy, as it matches my CPU. The CPU package power at idle, as reported by Intel Power Gadget, is the same, at about 1.5W, for me. This is measured with the display sleeping, which gives me the lowest reading, naturally. I lost only a very slight amount in...

www.tonymacx86.com

 

[michmill]

Had this issue with my laptop - easy solved I found is using CPUFriendDataProvider.kext providing the idle setting to CPUFriend.kext (add this Lilu plugins to clover/kexts/other) - with that i went from 1.3 idle to 0.9

So it turns out the solution was even easier that that. Not sure if this is a good idea, but it seems to work well.

SSDT-XCPM.aml was already added to /EFI/CLOVER/ACPI/patched as part of following RehabMan's guide. I left it there.
In the CLOVER/config.plist:

• I set Root/ACPI/SSDT/Generate/PluginType=No.
• I added Root/CPU/HWPEnable=Yes.
• I left SSDT, SSDT-XCPM, SSDT-PluginType1 still listed under Root/ACPI/DisabledAML as per RehabMan's original plist file.

That was it. I rebooted, and now I've seen the core frequency drop below 800MHz, and power consumption drop by an average of a Watt.

DISCLAIMER: I have no idea what other side effects there may be from disabling Root/ACPI/SSDT/Generate/PluginType. I'm hoping RehabMan weighs in to let us know if this will break anything else.

 

[favoriti]

I set Root/ACPI/SSDT/Generate/PluginType=No.

On my laptop this setting disable CPU PM....
Have you check CPU PM is still working when set to No ? Is ioreg indicates X86PlatformPlugin stiil loaded with full cpupstates indication ?

 

[michmill]

On my laptop this setting disable CPU PM....
Have you check CPU PM is still working when set to No ? Is ioreg indicates X86PlatformPlugin stiil loaded with full cpupstates indication ?

Where exactly in IOReg would I look for the CPU states? I poked around a bit, but didn't find anything called cpustates or X85PlatformPlugin.

I have noticed that when the laptop resumes from sleep, the min clock frequency is 1GHz. I don't see it drop down where it was before.

 

[favoriti]

Where exactly in IOReg would I look for the CPU states? I poked around a bit, but didn't find anything called cpustates or X85PlatformPlugin.

Use search X86PlatformPlugin (not X85) in IORegistryExplorer - if not loaded think CPU PM is not possible

 

[Fuu]

you can change LFM from your SMBIOS with FreqVectorEdit by Piker-Alpha, if your CPU not available on the setting, just add yours with data from ark intel... worked for me, my CPU is i3-6006U, lowest frequency mode at 400MHz but SMBIOS MacBookPro 13,2 only 1300MHz

 

[michmill]

Use search X86PlatformPlugin (not X85) in IORegistryExplorer - if not loaded think CPU PM is not possible

Sorry for the typo, favoriti. Yes, I searched for X86PlatformPlugin, and didn't find it. I'm guessing it wasn't loaded because I disabled plugins. Intel Power Gadget, however, is showing fluctuating clock frequencies, so I think HWP is working. I believe, but not sure, X86PlatformPlugin is of OS controlled PM vs HWP for CPU controlled PM. I think I might try Fuu's idea, though, since I'mm not sure what else disabling the plugin might break.

you can change LFM from your SMBIOS with FreqVectorEdit by Piker-Alpha, if your CPU not available on the setting, just add yours with data from ark intel... worked for me, my CPU is i3-6006U, lowest frequency mode at 400MHz but SMBIOS MacBookPro 13,2 only 1300MHz

Thanks, Fuu. I found my proc on ark.intel, but I don't see where it lists all the pstates. Also, I'm not sure how to "just add mine" once I do find the data. Is there a wiki or blog that describes the process?

 

[michmill]

I ran the freqVectorEdit.sh script from PikeRAlpha, restored the plugins and disabled CPU HPW in config.plist. The CPU will go lower than my original config, but I looks like HPW still gives me the best power savings. HWP compared to using plugin=1 + freqVectorEdit is almost the same, so with so little difference, I'm keeping the plugin enabled, and disabling HWP.