Why can the wi-fi signal on a laptop weaken?

Question

Iron

There is an asus n56vz laptop and the problem is that the signal level has dropped sharply, almost by half (according to the displayed sticks), according to the speedtest, the speed has dropped by almost 10 times, the ping has remained good, as before. The problem is definitely not with the router - it was checked on two networks in different places and everywhere the same thing. Before that, the laptop was handed over to the workshop for cleaning, could something be chemically done there? It's just embarrassing that the problem did not appear immediately, but after several hours of operation of the laptop after cleaning.
Actually, what could be the problem and what should be checked and corrected?
Thanks in advance for your replies.

Answer 1

check the antenna as an option. maybe jumped off

Answer 2

This also happens with a heavily loaded radio broadcast (interference or dots of neighbors). Play around with the channels, put auto or force the channel. What to put - it will be clear from the links below.
Here are some more good articles: Wi -Fi :
non-obvious nuances (on the example of a home network
) //yadi.sk/d/crTjQFYtRbh8f https://help.keenetic.net/hc/ru/articles/213968749 https://help.keenetic.net/hc/ru/articles/213968709 https://habrahabr.ru /post/117761/