Ubuntu – Low CPU frequency


I'm having the following problem with Kubuntu 15.10.
Sometimes when I put my laptop(Dell e6420) to sleep and later wake it up, I see that CPU is running at really low frequency (~600Mhz)

This is normal behaviour, just after fresh boot.
(Can't post images, yet)

This is wrong behaviour, after waking up from sleep.

The commands I execute to check CPU details are:

$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_driver<br>
$ cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor<br>
$ grep MHz /proc/cpuinfo<br>

This certainly is a bug. Do you know any possible solution to resolve this problem.
I heard that it has something to do with intel_pstate driver.

Best Answer

The CPU does that by itself to save power. It's normal behaviour for any laptop running any OS. Take a look in BIOS and see if you can find something like "CPU Power saving" or something like that. It should do the trick.

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