Netgear CM400 - High Speed Cable Modem—DOCSIS 3.0 Installation Guide

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Quick Start
High Speed Cable Modem
Model CM400
Package Contents
Cable modem
Ethernet cable
Power adapter
Coaxial cable
(not included)
Power adapter
Cable modem
Ethernet cable
Attachable feet
4.  Connect the power adapter.
Connect the power adapter to the cable modem 
and plug the power adapter into an electrical 
outlet.
When the startup procedure is completed, the 
Power LED 
 lights green. 
6.  Connect a computer to the 
cable modem.
Use the Ethernet cable that is 
provided in the package to connect 
a computer to the Ethernet port on 
the cable modem.
Reboot the computer.
5.  Wait for the cable modem 
to come online.
The cable modem comes 
online when the Internet 
LED 
 stops blinking and 
lights solid green.
This process might take up 
to 10 minutes.
3.  Connect a coaxial cable.
Use a coaxial cable that is provided by your 
cable company to connect the cable port on 
the cable modem to a cable wall outlet or a line 
splitter.
Make sure that the cable is tightly connected.
Note: 
If Comcast XFINITY is your cable Internet 
provider, Comcast XFINITY recommends connecting 
your cable modem directly to a cable wall outlet.
Note: 
If Charter is your cable Internet provider, 
Charter recommends connecting your cable modem 
directly to a cable wall outlet. If you must use a 
splitter, use a splitter that is rated at 3.5 dBmv.
2.  Turn off existing modems and routers.
If you are replacing a modem that is currently 
connected in your home, unplug the modem and 
plug the new cable modem into the same outlet.
1.  Collect your cable Internet provider 
information.
Collect your cable account number, account 
phone number, and login information (your email 
address or user name and password).
7.  Activate your Internet service.
For information about how to 
activate your Internet service, see 
on the 
other side of this quick start guide.
Note: 
After you install and activate 
the cable modem you can disconnect 
the computer and connect a router 
to the cable modem. For more 
information see 
on the other side of this quick start 
guide.
Computer