How to Disable (& Enable) Turbo Boost on a Mac
Many of the most modern Macs have processors which include a feature called Turbo Boost, this feature allows a processor to temporarily run above its standard clock rate when requested by the operating system. Turbo Boost can accelerate the performance of a Mac (or a PC for that matter) but it can also lead to increased energy usage, meaning the Mac may run hotter and the MacBook battery may drain faster when it is activated. Accordingly, some advanced Mac users may wish to toggle this feature themselves, manually disabling TurboBoost when they wish to prolong battery life at the expense of general computing performance. Of course, you can also re-enable Turbo Boost, which is the default state on modern Macs.
To accomplish this task, we’ll use a third party Mac tool called “Turbo Boost Switcher for OS X” that is compatible with OS X El Capitan but not MacOS Sierra (yet), this app also requires a modern Mac CPU like a Core i5 or Core i7. The utility will load and unload kernel extensions to force TurboBoost to be disabled or back to the enabled default state through user interaction with a menu bar item. This utility is truly only intended for advanced users, if you are not comfortable with the idea of modifying kernel extensions and the ramifications of that, using uncertified third party software, nor the idea of intentionally slowing down a Mac by disabling hardware features, this is not for you.
Novice Mac users should not use this application. Due to the nature of modifying a kernel extension, you should always backup your Mac before using any such utility. If you simply want to get better battery life in OS X El Capitan or Yosemite, follow these tips which are much less invasive.
Using Turbo Boost Switcher to Disable Turbo Boost in Mac OS X
- Head to rugarciap to download TurboBoost Switcher (there is a free and paid version available), you’ll need to bypass Gatekeeper to run the tool
- Once Turbo Boost Switcher has been launched, you’ll find the menu bar item in Mac OS X which is where you can toggle the CPU ability off and on again, pull down the menu and choose “Disable Turbo Boost” to turn off the boost feature on the Mac
- Authenticate when requested with an administrator password (necessary because this is a kernel extension) to complete the disabling of Turbo Boost on the Mac
With Turbo Boost disabled, you may notice the menu bar for battery life remaining tick up after it recalculates with the reduced energy use and slower clock speed. If you are doing anything that requires processor use, you will also notice a decrease in performance.
This feature is really best used only when you want to prolong battery life and don’t mind the performance hit, once you’re out of such a situation, returning to the default functionality of the Mac processor is recommended by re-enabling Turbo Boost functionality with the tool.
Re-Enabling Turbo Boost on the Mac
To return to the default state of the Mac and re-enable Turbo Boost, simply go back to the menu item and choose “Enable Turbo Boost”, and authenticate again. This removes the kernel extension that is preventing the feature from working.
Does Disabling Turbo Boost Help Battery Life?
Depending on usage, yes potentially, but at the expense of general computing performance. In other words, if you disable Turbo Boost, the Mac battery may last longer, but the computer will be noticeably slower. Whether or not that is worth the trade off depends on your use case, but in some select situations where performance is less important than a battery lasting longer, it could be useful.
Anecdotally I noticed nearly an hour increase in potential battery life when using the app to toggle Turbo Boost off on a new model MacBook Pro, but some users have reported more dramatic changes. According to Marco.org who ran some benchmark tests: “Disabling Turbo Boost hurts performance of CPU-intensive tasks by about a third, but doesn’t significantly slow down lighter tasks. The MacBook Pro also runs noticeably cooler, and gains about 25% more battery life.”
So, your mileage may vary, it really depends on how you use the Mac. Just remember to re-enable Turbo Boost on the Mac(Book) to get full performance back again.
Thanks to grunchitog for the tip idea left in our comments.