Network chip faulty? Need Help.

So my brother's ps4 (original) was on wifi but started dramatically fluctuating speeds and connectivity. So I had him hardwire into my router. It was fine for awhile and now it's doing the same thing but much worse. Fluctuating speeds, connectivity issues. It Barely connects to YouTube and Yu-Gi-Oh master dual. He has to load a video on YouTube like 10 times before it even tries to work. The ps4 gets downloads from 250mb down all the way to 50kbs down and that's within minutes.

My question is: is this the network chip dying? If so where/which one is it exactly so I can replace it. Thanks so much!!