Motorola SB6141 SURFboard DOCSIS 3.0 Cable Modem for $89.99 shipped. Here is a screenshot for reference. It has IPv4 and IPv6 support and speed up to 343Mbps. This is a relatively high-end consumer cable modem. Having your own cable modem often means you do not have to rent one from your internet service provider (ISP) with a monthly rental fee, which saves money in the long run.