Sometimes due to your BIOS/EFI you may find that you have chosen "Energy Efficient" for your CPU which may effectively disable turbo mode. This is because "Energy Efficient" will often restrict or throttle your CPU to the base speed. This can impact nearly any CPU such as Intel's, AMDs, Opteron, Xeon etc...
This is of course frustrating, for example if you have a CPU that is 2.0GHz base speed but turbo to 2.5GHz, you will never hit more than 2GHz. If you have a 3.6GHz CPU with turbo mode to 4GHz you may never hit more than the base 3.6GHZ.
Many people recommend using cpupower or cpufreq-set or cpupower which does work but can't easily apply to all cores/CPUs.
We can see below that it is powersave, likely set by the BIOS, but fortunately we can change it ourselves.
cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
powersave
powersave
powersave
powersave
powersave
powersave
powersave
powersave
powersave
powersave
powersave
powersave
echo performance | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
Check again, we'll see that the CPU governor is set to performance now:
cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
performance
performance
performance
performance
performance
performance
performance
performance
performance
performance
performance
performance
Some parts of the internet falsely claim the /proc/cpuinfo does not display any turbo frequency or anything above base but this is not correct.
watch "cat /proc/cpuinfo|grep MHz"
You'll see updates every few seconds that show the frequency your CPU is running at. Generate some activity by opening applications and other activities to try to make it hit higher frequencies.
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