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E7250 E7450: CPU power management and battery life

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Big thank you to Osxlatitude for your guides and support.


I went for the Virtualsmc guide for the e7250 and e7450, both working very well (Catalina).


Trying to improve battery life I found that p- and c-states are not checked in jakes plist.

I guess there is a reason for that, but now the CPU throttles down to core min. 1,2ghz only.


Checking P/C states in config it comes down to core min. 0,9ghz - but still far off from the 0,5 min value that the bootlog/clover shows to be the min. value next to the turbo values.


So far it appears that the macbook air 7.1 with p/c states checked runs best, but still (with hibernatemode left at 3) if I leave it sleeping; the battery of my e7250 empties in two days.

So it eats about 2% of Battery/h doing nothing.

(And MBPro12.1 with hibernatemode set to 0 drains even faster...)


Also the way graphics clocks is different between mbpro and mbair , see pics.


(My 7250 has a dw1560, 16g Ram and FHD screen - and just a tiny battery I guess)


Is there anything else I could try to improve this - are others experiencing the same ?





air7_1_p_c_states on.png


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Generate P States and Generate C States are settings applicable to old C2D/C2Q/1st gen Core platforms only. They do not apply to Sandy Bridge platforms and beyond, including Broadwell platforms such as yours. In fact, if you call on these, you may find your CPU switching only between that low frequency you reported and the highest nominal frequency; all without Turbo boost and intermediate frequencies, which means CPU inefficiency and hammered performance.


In order to enjoy proper CPU power management on your Broadwell Latitude laptops:

  • either you apply/select/set/tick PluginType option in Clover ACPI section to which you may add Plugin Type=1.
  • or you drop SSDT tables with ids CpuPm + Cpu0Ist in Clover ACPI section and generate your CPU-specific power management SSDT with Pike R Alpha's good old SSDT generator script; you'll then place the generated SSDT table in E/C/ACPI/patched folder.


E7250/E7450 are fitted with low-power CPUs such as i5-5300U/i7-5600U and you should expect idle frequencies of 800MHz. If Intel datasheets do indeed indicate LFM frequencies as low as 500 or 600MHz, I'm pretty sure these are reserved for the programmable TDP-down/7.5W reduced power mode. In fact, if you download and install Pike R Alpha's complete tool and consult the data files for the Broadwell CPUs, you'll see this:

# Broadwell mobile processor data.
# 5th generation Intel® Core™ i7 Processors (socket FCBGA1164)
# 5th generation Intel® Core™ i7 Processors (socket FCBGA1168)
# 5th generation Intel® Core™ i5 Processors (socket FCBGA1168)
# 5th generation Intel® Core™ i5 Processors (socket FCBGA1364)
# 5th generation Intel® Core™ i3 Processors (socket FCBGA1168)

which lists CPU model, TDP, LFM, HFM, max Turbo, cores and threads. LFM frequencies of those CPUs fitted to our Latitude E7250/E7450 are therefore set at 800MHz, even though you may not encounter them much due to sustained minimum load under macOS.


In the same respect, HD5500 iGPU of those processors typically clocks between 300 and 900/950Mhz. With regards to iGPU throttling, bear in mind that your Hackintoshes are not fitted with the same CPUs and iGPUs as those real Macs we fake them to be. For instance former are fitted with HD5500 GT2 iGPUs when latter are fitted with HD6000/Iris 6100 GT3 iGPUs. Not entirely the same thing...


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I went with MacBook Air 7,1 and adding p-c-states.

(Broadwell does seem to support this, and clover generates p and c states according to log)

I don't know the exact difference to "plug-in type", but this now gives good sleep / wake up and battery life is ok too.

Frequencies over all seem to be smoother (looking at intelpowergadget)

The plist is based on Jake Lo`s original (plus the above mentioned changes)

Thanks again 


acpi_macbook Air 7.1.png


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Incorrect settings, you should:

  1. remove Generate C States and Generate P States (these are for C2D, C2Q, 1st gen Core CPUs)
  2. enable PlugInType

and that's it, nothing else. No need to enable NoOemTableId or NoDynamicExtract afaik.

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I added cpufriend kexts (credit stevezheng GitHub script) for the i5 5300U @ 800mhz, and set plugin-type to 1 and disabled p-c states.

Core min shows 0.7 now.


I am using Appleps2controller kext, I couldn't find a better (voodoo/drhurt/alps) solution.

The only downside being that Brightness keys f11/12 don't work now - help appreciated.

Other than that everything is fine for now, here's the Folder for Catalina:




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