Ubuntu how to change CPU max MHz?

Screenshot of terminal

Hi i have set my cpu frequency to 3900 MHz in my bios however on the lscpu in the terminal it is showing different values? is there a way to change this I have no idea as im new to using linux and ubuntu.

2 Answers

Your processor should use the intel_pstate CPU frequency scaling driver by default. You can change the maximum CPU frequency to 3.9 GHz via:

echo 3900000 | sudo tee /sys/devices/system/cpu/cpufreq/policy*/scaling_max_freq

or via:

echo 76 | sudo tee /sys/devices/system/cpu/intel_pstate/max_perf_pct

(Rounding might require 77%)
Neither method will persist through re-boot. What you want is very close to just disabling turbo, 3.8 GHz, so you could do that in BIOS. If you want to do it from the OS, which would be non-persistent:

echo 1 | sudo tee /sys/devices/system/cpu/intel_pstate/no_turbo 

This answer uses primitive commands. Others might give answers that use higher level tools to do the same thing.

EDIT: Actually, it looks as though you might already have turbo disabled in the BIOS, in which case you will not be able to get to 3.9 GHz. Do this:

grep . /sys/devices/system/cpu/intel_pstate/no_turbo/*

to see your current operating parameters.

Go to and search for "CPU freq"...

Note: Understand that setting your CPU frequency too high might cause it to overheat, and/or the fans to be less than silent. It may also effect your battery life. Overclocking the CPU or RAM can cause other problems.