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mb8600 | 1Gbps DOCSIS 3.1 Cable Modem - Comcast Replacement

"I wanted to save $15/month and upgrade from my ISP’s modem. This has helped get the speed I pay for."


mb8600 | 1Gbps DOCSIS 3.1 Cable Modem - Comcast Replacement

$129.99 $169.99 saving $40.00
| /
  • Compatible with Xfinity, Cox, Spectrum & more
  • Save up to $168* per year vs renting
  • 2 year warranty, Unlimited Support
$129.99 $169.99 saving $40.00
| /

"I wanted to save $15/month and upgrade from my ISP’s modem. This has helped get the speed I pay for."


  • Description
  • Tech Specs
  • ultra-fast DOCSIS 3.1 performance

    Get the speed you’re paying for. DOCSIS 3.1 supports speeds up to 10x faster with higher efficiency. Designed for fast internet plans and backwards compatible with 32x8 DOCSIS 3.0.

    true Gigabit speed

    Experience next-level gaming, streaming, and conferencing with a 1 Gbps Ethernet port for faster downloads and uninterrupted connections.

    works with any router

    Seamlessly pair with any WiFi router to connect all your wireless devices. This cable modem does not have a built-in wireless router or telephone capability.

    superior, but pays for itself

    Savings up to $168 per year on modem rental fees with your internet provider. Certified for Comcast Xfinity, Cox, and Spectrum and compatible with IPv6.

    simple setup and use

    Easy self-installation. Comes with a 2-year warranty and free support from our team of US-based technicians.

    motosync app

    It's like having our product experts in your home with one tap using in-app live chat support.

  • General

    Cable Modem Service Interface

    • F-type female 75 Ω (standard coaxial connector)

    Ethernet Interface

    • One open and 3 masked 10/100/1000 Ethernet LAN ports†


    • Front Panel:
      Power, Downstream, Upstream, Online, LAN
    • Rear Panel:
      Each Ethernet port has two LEDs indicating data flow and LAN connection speed. Green indicates 1 Gbps; amber indicates 10 or 100 Mbps. Blinking indicates data flow.


    • 7 7⁄8" tall x 7 1⁄4" deep x 2 1⁄4" wide
      (200 mm x 184 mm x 57 mm)


    • 18.4 ounces (523 grams)

    Power Adapter

    • DoE-compliant Level VI energy-saving, UL-listed power adapter with 12 Volt DC, 2.5 Amp output and 100-240VAC universal input
    • NEMA 1-15 (North American style) 2-prong plug is provided in the US.

    Operating Temperature

    • 32° to 104° F (0° to 40° C)


    • FCC 15B and 15C, FCC MPE, Bureau Veritas 60950-1 ITE safety, CableLabs®, cable service providers

    Surge Protection

    • Ruggedized cable and power lightning protection


    • Two years

    Operating Parameters

    DOCSIS Standards

    • DOCSIS 3.1, 3.0, 2.0, 1.1


    • Data Rate:
      Up to 6,000 Mbps*
    • Bonded Channels:
      Up to 32 SCQAM (DOCSIS 3.0) or 2 OFDM (DOCSIS 3.1)
    • Frequency Range:
      108 to 1002 MHz
    • Operating Level Range:
      -15 to +15 dBmV


    • Data Rate:
      Up to 800 Mbps*
    • Bonded Channels:
      Up to 8 SCQAM (DOCSIS 3.0) or 2 OFDMA (DOCSIS 3.1)
    • Frequency Range:
      5 to 85 MHz
    • Configurable Diplex Filter: 5-42 and 5-85 MHz
    • Operating Level Range:
      +65 dBmV (64 QAM, single channel)
      +57 dBmV (64QAM, 4-8 channels)
      +65 dBmV (16 QAM, single channel)
      +65 dBmV (OFDMA)

    Network Protocols


    Application Protocol

    • Automatically retrieves IP and DNS server address from DHCP server through WAN connection

    DHCP Client

    • SNMP v1/v2/v3


    • Web-based management interface utility

    System Requirements

    • The cable modem must be connected to a cable modem service that uses any of the DOCSIS standards – 3.1, 3.0, 2.0, 1.1
    • The supplied power cube plugs into the most common USA power outlet.

    Package Contents

    • DOCSIS 3.1 / 3.0 Cable Modem (does not include router or phone jacks)
    • Power Adapter (UL listed)
    • Ethernet Cable (Cat 5e)
    • Quick Start Flyer

    * The actual download speed of this modem is slightly less than 1,000 Mbps when connected via a single GigE Ethernet port. The modem supports Ethernet port bonding via LAG to devices that support bonding. When connected via two bonded Ethernet ports, the actual download speed is slightly less than 2,000 Mbps. The speed may also be limited by the speed of your Internet service and other factors.

    ** This cable modem does not have a built-in wireless router and does not have telephone jacks for support of voice phone calls.

    † One open and 3 masked LAN ports allow connection of any SINGLE device with an Ethernet port including a router, Windows/Mac computer, HDTV, game station. The multiple Ethernet ports are not for connecting multiple devices; they allow connection to a router that can bond more than one Ethernet port to achieve speeds over 1 Gbps when supported by your cable service.

Customer Reviews

Based on 11 reviews
Good choice for replacement modem

Modem works well, very easy installation. Only noticed a slight increase in download speed over the 3.0 modem it replaced, but a 3x increase in upload speed. Overall, very happy with the value of this modem.

Deb B.
Excellent replacement for what I had

Seems to be all I hoped for so far, just installed it yesterday. Our other modem was pretty old in today's standards, so it was needed. I researched several replacement choices and this one was a very good deal for the price with all it can do.

Greg K.
Motorola Cable Modem - MN8600

Very easy to setup and activate with Xfinity Comcast using the mobile app. I am now up to spec as they required.

Peter A.
Xfinity Approved Modem Does the Job

This modem replacement was only because Xfinity threatened a discontinuation of internet service at an approaching date because the modem would no longer be considered compatible. While activating the modem and getting wireless service functioning again was completely maddening with Xfinity customer service, the Motorola Gigabit Speed DOCSIS 3.1 Cable Modem mb8600 is functioning faster than the previous modem, giving truth to the threat that eventual incompatibility would have been an issue. It's functioning as advertised. I would recommend it so far (3 weeks) for our lower-level home internet performance package.

Xuyang L.
Nice Product

The Motorola Gigabit Speed DOCSIS 3.1 Cable Modem mb8600 is one of the replacements for Comcast. I choose this to replace the soon-to-be incompatible old modem. It worked out flawlessly. The set up process is very easy if directions are followed. It took me about 10 minutes to finish. The modem has been working as advertised. It seems to be well designed and made.
This modem offers a minimum setup needed for Comcast with a single Ethernet output. A separate router is needed if a wireless hotspot is needed. I already have a wireless router and a switch, so I chose this model. Everything works after the modem is activated through Comcast.