Time Warner Cable (TWC) and a few other internet providers can do a sneaky thing (probably stated in their terms of service somewhere) where they throttle your internet download speed when streaming (and uploading) a youtube (or similar stream based sites such as Netflix, Hulu, Twitch, etc.) video.
I have the basic Time Warner Cable package that includes phone, cable and internet. Using speedtest.net, I normally had anywhere from 1-10 mb/s download, and always under 1mb/s upload (when I was paying for 15mb/s). This is because Time Warner Cable was throttling the internet.
Note: some speed test websites can show inaccurate results. Try using a couple unaffiliated speed testing sites such as google.
Use Google's public DNS
A quick tip for speeding up all websites, even if only a little is by changing from your current, default DNS to Google's. A DNS is essentially a phone book for the internet. When you go to a website, your computer (or router) performs a DNS lookup before it downloads it. Routers will often default to use your internet service provider's DNS. To change your router's DNS to Google's public DNS for faster and more secure DNS lookups:
Go to your router's home page (common one is 192.168.1.1) and navigate to the internet section. On this page, you should find a Domain Name Server (DNS) Address header. Remove any default values (or change it to Use These DNS Servers) and enter
126.96.36.199 (the second one is an alternative). Restart your router and you should be using Google's public DNS servers!
TWC may put a limit on the download, or stream, speed that you can download from sites like YouTube, Twitch, Netflix and Hulu. Each time you open a video, your computer connects to a server, one that TWC has inherently throttled. Luckily, there is an easy fix to this problem. You'll need to block the primary connection that is requested. It will then request the default, faster, server (which will speed up the download speed tremendously).
There is an short, easy method of adding this IP block using the command prompt and a longer, more user interface friendly version. They both do the same thing – hope you can follow one of them.
Start -> type
Type the following into the command prompt:
netsh advfirewall firewall add rule name="TWC SUCKS" dir=in action=block remoteip = 188.8.131.52/24,184.108.40.206/16 enable=yes
Hit enter (You should get a confirmative "Ok.")
That's it. Now it should default to the faster IP when requesting certain sites.
Note: to undo this, type the following:
netsh advfirewall firewall delete rule name="TWC SUCKS"
Start -> type
Click InBound Rules (top left)
Click new rule
Check custom -> next
Check all programs -> next
Leave the default settings -> Next
Under REMOTE IP addresses, check These IP addresses -> Add:
Block the connextions -> Next
Keep Domain, Private and Public all checked -> Next
Give it a proper name and description -> Finish