cpufreq gnome extension keeps reverting to powersave

In your /etc/init.d/cpufrequtils file change:

GOVERNOR="ondemand"

to:

GOVERNOR="performance"

Leave the rest of the line as is. Save and reboot.

TL;DR - old answer below

As far as Intel speed governors go:

• ondemand mode was deprecated years ago.
• performance mode has little improvement over powersave mode.

That said your processor may not even support picking between performance and powersave.

To view available speed governors use this command:

$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors 
performance powersave

If you do have more than one governor you can check what is currently in use with this command:

$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
powersave

To change your processor to performance mode use:

$ echo performance | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
performance

You will then notice CPU% utilization drop by about 5% but also notice speed will increase from about 1000 MHz to 3000 MHz and temperatures will spike by ~10 degree, depending on your processor:

I have noticed that even when set to powersave mode (as I always use) when Ubuntu first boots it runs in performance mode for 90 seconds before it eventually kicks into powersave mode.

None-the-less after manually setting the governor to performance mode using the appropriate command above. It has stayed in performance mode for 10 minutes now as confirmed by using the appropriate command above and doubly confirmed by conky display above.

I left the governor set on performance for 30 minutes and it worked just fine. It might interest some readers what the conky display looks like when switching off of performance governor back to the default powersave governor:

CPU% utilization has spiked by 5%, but CPU frequency has dropped by 1500 MHz and temperature has decreased by about 10 degrees. Overall I think powersave mode is the best for most configurations.