Extremely slow wi-fi, tried everything I found - Wireless Networking
Hey Whitestar_999 I just made an account on this site just to tell you how grateful I am for this answer! You are a moderator so I guess my "like" doesnt matter but you saved me up a lot of hustle ! Something was clocking my internet speed to 0.5 of my actual speed (weather it was on my wifi or on my mobile's network) and I was certain that my network card was not the issue.
For other users: Search for "smartbyte" on windows search and it will open up a program, click on it and once the window pops up, you'll see just one option you can disable

What it does when it is enabled is that it clocks down your internet speed and prioritizes certain processes over others (like giving priority to video streaming instead of, for instance, downloads)