apt install cpufrequtils

more /etc/init.d/cpufrequtils

cpufreq-set -g powersave

cpufreq-info

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lscpu

cat /proc/cpuinfo | grep -i ‘mhz’

grep -E ‘^model name|^cpu MHz’ /proc/cpuinfo

cat /sys/devices/system/cpu/cpufreq/policy7/scaling_governor
cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq

**performance
for CPUFREQ in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do [ -f $CPUFREQ ] || continue; echo -n performance > $CPUFREQ; done

**powersave
for CPUFREQ in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do [ -f $CPUFREQ ] || continue; echo -n powersave > $CPUFREQ; done

echo “powersave” > /sys/devices/system/cpu/cpufreq/policy0/scaling_governor

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