ARRIS SURFboard SB8200 DOCSIS 3.1 Cable Modem for $113.13 shipped after clipping a $20 off coupon. 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 and is on the approved list of several major cable ISPs. 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. Most places have this cable modem for about $165.