Comment 76 for bug 1768976

Same problem here.
Ubuntu 18.04.3 LTS
I tried kernels 4.15, 5.0 and 5.3 and the problem persists.
With default installation parameters CPU temperatures goes above 95° very easily.

The only way I managed to keep the CPU temp down is:
a) setting
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash intel_pstate=disable"
and then choosing "PowerSave" mode in cpufreq

b) Installed laptop-mode-tools
Edited file: /etc/laptop-mode/laptop-mode.conf
It changed the file /proc/sys/vm/laptop_mode to 2
After that no significant changes in temperature when moving from AC to Battery

Attached hardinfo_report.html run after the doing the procedures above mentioned