I am running Ubuntu Mate 16.04 on a laptop with a tendency to overheat (and with a noisy fan).
Until recently I was using the previous LTS, 14.04, and there the CPUfreq notiication area applet gave me a variety of CPU frequencies to choose from, as well as four named options (performance, powersave, on-demand, conservative). I used to reduce it to keep the computer quiet when speed was not necessary and it worked well.
Since I switched to 16.04 the same applet gives me only two options (performance, powersave), and none of them seems to make any difference. In both conditions the CPU speed seems to be changing automatically as needed, and reaching maximum speed (heat, fan noise).
Why can’t I control the CPU speed as I could before? Can I do anything to regain control over the CPU frequency and limit it manually when I want to keep the computer cool and silent?
Thanks in advance for any help.