Comcast High-Speed Cable With Comcast High-Speed Internet, surf the web at lightning speed - up to 4x faster than 1.5 Mbps DSL, 7x faster than 768K DSL and 100x faster than 56K Dial-up. And now with PowerBoost, Comcast's super fast Internet connection gets even faster, with an extra burst of speed up to 12 Mbps when you're downloading large files like videos and games.
