Kernel cpu frequency control to lower the power consumtion and fans noise without the need to set up the frequency limits using BIOS settings.

cpu-frequency-control.sh

#!/bin/bash
# Created By: misraX
# Github: github.com/misrax
# License: MIT
# CopyWrite: 2017
# A very basic shell script.
# Tested in archlinux 
# kernel: 4.11.9-1-ARCH, cpupower: 4.12-1, bash: 4.4.12
# To control the frequency of my Lynnfield Core i5 760 CPU. In a very hot weather :D 

# Kernel cpu frequency control to lower the power consumtion and
# fans noise without the need to set up the frequency limits using
# BIOS settings.

# getting the frequency info
#cpupower frequency-info | grep -e "available frequency steps"
echo "The availabe frequency steps supported by your CPU are:"
# PIPES PIPES PIPES awk (is fun) :D 
cpupower frequency-info | grep -e "available frequency steps"  | awk '{ 
for(i=1; i<=NF; i++) 
   { 
      if ($i ~ /[0-9]+\.[0-9]*/) 
     {
        printf("%sGHz \n",$i)
     } 
   }
}'

echo -n "Chose one of the following frequency spacewise and press [ENTER]: "

# Read frequency from user input.
read freq

# check if it's an empty input
if [ "$freq" == "" ];then
	echo "Please enter a valid frequency,"
	echo "ex: 1.86GHz"
	echo "Exiting...."
	# exit if empty.
	exit 1
else
# seting a frequency in GHz or MHz without any space
cpupower frequency-set -f "$freq"
# watching the cpu power every 2 second.
watch -n2 --exec cpupower monitor
# The end
fi
# A switch case statment to chose the desired state, To know the available states
# You have to call the cpupower frequency-info, this will outpout the available
# frequency steps in GHz (cpupower version 4.12-1)