Even if the question may go into the technical details of a laptop computer specifications, I would like to know general experience of travellers concerning that topic.
Some airlines offer power sockets at their seats where it is possible to plug a computer. So far, I have not been able to know limitations of the supplied power, such as maximum power output.
In my current case, I have an Acer Predator Helios 300 as my main laptop. It is a gaming-grade machine, meaning it should suck a little more power than the average MacBook. I do not find a clear power rating indication in watts, and intelligent power management of nowadays should modulate the actual power drawn according to the current usage. Let's say that typing documents requires less power than playing a top-tier 3D game.
Each time I plug it in, the green light on the airplane socket goes off. It means that the breaker has tripped, likely because I am trying to draw too much power. Surprisingly, it also happens when I plug the charger alone without the laptop at the other end. This was my experience so far on Delta and United.
I usually ride trains quite a lot in Europe. Rail cars are equipped with sockets nowadays and my laptop was powered by them without issues in all situations. In France, for instance, the train sockets are labeled 100 watts max, therefore my laptop should be drawing less. So, why is is a problem when done in airplanes?