wifi is constantly spiking up and down, making it unable for me to play online games

wifiproblem

Reputable
Aug 6, 2015
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0
4,510
So basically, my internet used to be fine. But after I left the house for two months I come back to this. http://imgur.com/7zQMS2j
My internet is constantly spiking up and down, causing extreme lag while playing online games. My downloadspeed while downloading something however is pretty much unchanged?

edit:
I just bought a cheap ethernet cable and hooked it up, now it works perfectly. Anyone who knows what's wrong with my connection?