On my Lenovo T480 I ran in to a nice issue where the fan was constantly blowing and CPU was always over 4 GHz never clocking it self down. In Windows power management, it was set to balanced as it should, changing between power plans had no effect, always CPU at max speed. When I started googling about the issue I ran into different forum threads describing the same issue with people saying that Windows Power Management setting sometimes get corrupted and that the only fix they found is a re-install of Windows which for me was an unacceptable solution…

What actually helped me get around the issue was when i changed the CPU minimum and maximum speeds in power management. Basically I changed the minimum to 1% instead of 5 and max to 90%, applied the settings noticed the CPU clocked down instantly to 0,89 GHz like it was supposed to be, then reset the “Balanced power plan” back to it’s default settings and now the CPU speeds are as they should be 0,89 GHz while idling and over 4 GHz when under load.

For those who need more exact directions here is the step by step:

  • Open up the “Start menu” by pressing the Windows key and type Edit Power Plan and press enter/or just double click it with the mouse.
  • Click on “Change advanced power settings
  • Go to the “Processor Power Management” subsection and from there on move to “Minimum Processor State” change the values for both “On battery” and “Plugged in” from their default value of 5% to 1%.
  • Next change the “Maximum Processor State” values for “On battery” and “Plugged in” from their default value of 100% to 90%.
  • Click “Apply” to apply the changed power plan.
  • After applying the altered power plan click on “Restore Plan Defaults” and “Yes” in the prompt that pops up warning you that the power plan settings will be reverted to their default values. And then click “Apply” as the final thing.

And that should be it,  now your computer should be changing its CPU speed based on real needs.