Best answer as chosen by user edwardnav: Some Networks Don't Work Well With "DNS Client" Disabled
AT&T is a telephone line... Time Warner is Cable.. It can make a difference.
In your case, if your new cable network needs the DNS Client service enabled to allow internet connection, then you'll need to do so.. Unfortunately, with both a large HOSTS file and DNS Client enabled, you may have a real problem with the "slows". It may cause the computer to creep along at an unbearably slow pace . You may need to find a different ad-blocker for your system, or a much smaller HOSTS file, if the computer's performance suffers greatly.
I had a similar problem on a large government network, when using Windows 7, and I was unable to use a large HOSTS file on certain computers.
Hope this helps.