Internet speed slower through ethernet?

[scaryjam823]

So for some reason today my computer decided to not operate at my full internet speed. On wifi I get anywhere from 2700kb/s to 4000kb/s. My computer has always worked at this speed, until today. When I download something or try to load webpages it operates at a whopping 150kb/s. Meanwhile on my phone and other wifi devices I get my full internet speed. 

 

I have tried the following to fix it:

Take my static ip off and let the router give me desktop an ip address - no change

Tried resetting everything in my router, from QOS to firewall etc. - no change

Tried ipconfig /release and ipconfig /renew - no change

Tried disabling all extra network adapters in device manager (hotspot shield, microsoft ISATAP #1-6, virtual miniport adapter 1 and 2, virtual box host ethernet adapter) - no change

Reset the router, modem and computer several times - no change

Tried a different ethernet cable - no change

Plugged a laptop into the router using a different cable and my desktop cable - no change

Tried plugging cable into different port on the router - no change.

 

I'm at a loss as to what it could be and have no idea what to try. When I run speed tests it starts at 150kb/s, jumps to 500 kb/s then back down to 150kb/s - 180kb/s. It feels like something is throttling my computer but I cannot figure out what it could be. It worked fine the last I was on my computer, went two days not being on it and I'm greeted with this problem. Any advice to look into would be greatly appreciated. Router is an asus rtn66u

[Cacao]

Have you tried.... *drumroll*.... changing the cable?

[Nico123473]

Did you restart your computer?

[Clyne]

Reset the modem and router, check the cables outside if their loose. 

[scaryjam823]

Have you tried.... *drumroll*.... changing the cable?

Yes it is not the cable, forgot to mention that. The cable is only a few months old and a cat 6 cable. I just tried connecting a laptop to my router through both a different ethernet cable and the one going to my desktop, it had the same problem. That leads me to believe it is an issue with the router, it is an asus rtn66u. Computer has been restarted multiple times as well as the router and modem.