Home / Collections / All Products / Motorola DOCSIS 3.0 24x8 Cable Modem, up to 830 Mbps speed | mb7621

mb7621 | 830Mbps DOCSIS 3.0 Cable Modem

"Didn’t realize how much my old modem was reducing my bandwidth until I installed this modem. Totally worth it." –Jeff

mb7621 | 830Mbps DOCSIS 3.0 Cable Modem

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

"Didn’t realize how much my old modem was reducing my bandwidth until I installed this modem. Totally worth it." –Jeff

  • Description
  • Tech Specs
  • high-speed DOCSIS 3.0 performance

    Compatible with major U.S. cable Internet providers including Comcast Xfinity, Cox, Spectrum and others.

    fast, reliable Internet

    Supports cable Internet service plans with speeds up to 600 Mbps for faster downloads, HD streaming, and better gaming.

    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.

    extreme cost savings

    Save up to $168 per year on modem rental fees with your Internet provider.

    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.


    Cable Modem Service Interface

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

    Ethernet LAN Interface

    • RJ-45 10/100/1000 Mbps Ethernet, with Auto-MDI/MDIX

    Status Indicators

    • Front panel:
      Power, Downstream, Upstream, Online, LAN


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


    • 16.3 ounces (462 grams)

    Power Adapter

    • DoE-compliant Level VI energy-saving, UL-listed power adapter with 12 Volt DC, 1.5 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, 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 3.0, 2.0, 1.1


    • Data Rate*:
      Up to 1029 Mbps*
    • Bonded Channels:
      Up to 24 SCQAM
    • Frequency Range:
      108 to 1002 MHz
    • Modulation:
      64 or 256 QAM
    • Operating Level Range:
      -15 to +15 dBmV


    • Data Rate*:
      Up to 246 Mbps*
    • Bonded Channels:
      Up to 8 SCQAM
    • Frequency Range:
      5 to 42 MHz
    • Modulation:
      QPSK, 8QAM, 16QAM, 32QAM, 64QAM,128QAM,256QAM
    • Operating Level Range:
      +65 dBmV (64 QAM, single channel)
      +57 dBmV (64QAM, 4-8 channels)
      +65 dBmV (16 QAM, single channel)

    Network Protocols


    Application Protocol

    • SNMP v1/v2/v3

    DHCP Client

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


    • 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 – 3.0, 2.0, 1.1

    Package Contents

    • Cable Modem
    • Power Cube (UL listed)
    • Ethernet Cable (Cat 5e)
    • Quick Start Flyer

    * 1029/246 Mbps is the maximum nominal download/upload speed for 24x8 DOCSIS 3.0 cable modems. Actual speeds depend on a number of factors including the speed of your cable modem service, and will typically be slower. Speeds cannot exceed the speed of the Gigabit Ethernet port.

Customer Reviews

Based on 62 reviews
Lauren P.
Working great

Seems faster-i’m happy with it.

Earl A.

Motorola DOCSIS 3.0 24x8 Cable Modem, up to 830 Mbps speed | mb7621 - Comcast Replacement

Ronald D.

I,ve had the modem for a week now. It,s worked fine. I dont have wi-fi so this stand alone modem was reasonably priced and all I needed.

Manuel B.J.
Easy setup

I plugged the new modem in and connected it with the comcast app. Easy setup.

George H.
Woks great.

[****]. Comcast's web site made it hard to connect. After a lot of frustration I had t install an App to make it work.