Screen flickring caused by weak wireless signal?

I moved my wireless router to another room yesterday. Later I found my early 2015 mac pro with manjaro gnome start a weird screen flickering.
While I trying to fix this issue, I found out that the frequency of flickering is not constant, While I stayed in Terminal, the frequency is pretty low, Once I start my browser, my screen blinkering like crazy. So I concluded the issue is caused by rendering and start to try several solutions provided by this forum. but in the end none of them fixed my problem, So I erase my laptop and did a clean installation.
Since I live in China. internet connection without proxy can cause stuck in installing process. So I did installation offline. And everything worked fine. After installation is done and reboot. I reconnected to the internet, the flickering is back!
I spend some time try to single out the real causation, so I switch to different routers, move my laptop around the room.
Finally I found out my screen flickering issue is caused by weak wireless signal. It’s really weird.