I compare the work of the system on Windows and Ubuntu 20.04.
The problem is mainly under heavy load and the video card and processor.
In Windows, I could open several browser tabs, watch videos on YouTube in parallel and play games.
In Ubuntu, the system itself feels much smoother than in Windows (this is a plus). But during the load, it begins to slow down. The system starts to work in jerks (the same mouse movement). Overheating was not detected in this case.
So the question is this: because of what can the system slow down under load on pure ubuntu?
(TurboBoost - off, powersave - off. The same was in windows and now in ubuntu)