Everything was working fine with my new cable modem (Arris DG860A).
But after uploading 28GB (full backup of C: ) to my Cloud Backup Service (see pic for my internet usage), notice how my ISP immediately throttles my Internet service.
They basically disconnected my modem the next day, and they forced a new IP address for my modem (I've had the other IP address for over a year).
They must think I am running a server on my residential service...
This is *NOT* a router problem, folks.