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In Windows (Linux too), you have the very useful "Power saver" mode that limits the maximum frequency at which your CPU runs.

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Is there something similar in OS X?

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  • You could do that with Energy preferences in earlier versions of Mac OS X but not in Lion.
    – lhf
    Commented Jul 9, 2012 at 20:59
  • @lhf: huh? why did they take it out? Is there no other way?
    – houbysoft
    Commented Jul 9, 2012 at 21:23
  • OS X does a quite decent job in managing CPU speed automatically so I don't think you would gain much from doing it manually.
    – nohillside
    Commented Jul 10, 2012 at 12:49
  • @patrix: as far as I can tell what OS X is doing is just what "Balanced" in Windows or "ondemand" in Linux do. This is not always what I want.
    – houbysoft
    Commented Jul 10, 2012 at 13:43
  • It would be really nice with a setting that says "Please do not start the fans but throttle down the CPU instead". Commented Feb 16, 2021 at 10:30

5 Answers 5

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No. OS X doesn't have a CPU or even GPU throttling lever that users can toggle.

There is a nice app, gfxCardStatus to know which of the two GPU is engaged on Macs that have two options. It also allows pinning to the higher or lower power consumption which might be of use. It's not clear if there is no way to get past the OS to exercise control of the CPU or just that no-one has programmed it yet.

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    You should point out that CPU throttling is enabled by default and handled smartly by the OS. When the OS detects the computer running on battery power, it will scale accordingly. There is little need for a user to intervene with the throttling.
    – user10355
    Commented Nov 13, 2012 at 5:02
  • @cksum Indeed - the power management is so good lately, I've stopped even looking for articles describing how it all works. I almost didn't answer this linking to gfxCardStatus since I've seen good people install it and then conclude their Mac's are defective and end up with several repairs before realizing the bad graphics behavior was this tool interfering with the proper drivers and controls.
    – bmike
    Commented Nov 13, 2012 at 17:57
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Mac OS X has SpeedStep built into the kernel and enabled since OS X 10.4, and, as already has been said, it can no longer be controlled through the System Preferences. There are, though, some applications which will let you configure and set specific clock speeds. All of which I could find, such as CoolBook, do not work on Lion nor support the latest processors.

I could find, though, CPULimit. A script / tool which will let you control the usage of a specific process.

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Though Windows and Mac OS X run on x86 platforms , AFAIK, power consumption is handled differently in both the OSes and in Mac OS X it is slightly better. It is better not to use third party tools to manipulate CPU speeds as far as possible. Cheers

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    If I run an application at 100% CPU usage, the estimate time left on a full battery is around two hours. If I keep the processor more or less idle, I easily get seven hours. It is definitely better to limit the load on the system to get better battery life.
    – houbysoft
    Commented Jul 15, 2012 at 16:08
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In fact , there is GPU power state management in Mac OS X. The kext responsible is AppleGraphicsPowerManagement.kext into Extension Folder.

According to the GPU Core Throttle % ,changes the Power States from 0-4. But I don't know how the kext works for CPU states, this is something I am investigating.

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Though intently made for undervolt, Volta offer cpu power limit as well as turbo boost enable.

The developer had stop update by 2017(See link above for detail), but the power limit function and turbo boost disable still work now in macOS11 Big Sur.

One thing to notice, custom SIP shall be enable to utilize and os update may loss SIP state which require reset csrutil.

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