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Motorola SB5120

details: SURFboard 5120 - Ethernet and USB connectivity.
hardware type: Cable Modem
date added: 2006-01-23
updated: 2015-01-27
The SURFboard 5120 is CableLabs DOCSIS 1.1 and 2.0 Certified cable modem with both Ethernet and USB client connectivity. With integrated A-TDMA and S-CDMA technology this router provides WAN throughput of up to 38Mbps. It also supports TurboDOX bandwidth optimization.

As with earlier models, the 5120 has a convenient stand-by button that allows the user to disconnect client PCs without disconnecting the modem from the cable network.

The 5120 provides for easy troubleshooting through either the front panel status indicator LEDs or the web-based online diagnostics page.

» Forums search for Motorola SB5120
 SB5120 Features
 Availability: discontinued
 Street price: $75
 LAN / WAN Connectivity
 WAN throughput: 38 Mbps
 WAN throughput upstream: 30 Mbps
 WAN ports: 1
 WAN port(s) type: Coax F-connector
 LAN ports: 1
 LAN ports type: 10/100 Base-TX (RJ-45)
 LAN ports auto cross-over: no
 USB port(s): 1
 Cable Modem
 DOCSIS compliance: DOCSIS 1.1
 Cable Diagnostics: yes
 Device Management
 Default IP address:
 Default admin username: n/a
 Default admin password: n/a
 Administration: Web-based (LAN)
Remote centralized management
 Firmware upgradeable: yes
 Event log: yes
 Misc hardware info
 Power over Ethernet (PoE): no
 Product page:

Please use the Add Comment function below to review devices you have used (please be descriptive). If you find an error in our database, or have additional information about the product, please
  User Reviews/Comments:
by YeOldeStonecat - 2006-05-10 22:05
Did quite a bit of reading on many broadband forums...when I was about to move from DSL to cable. Was searching for what appeared to be the most well liked cable modem...the 5120 seemed to get the most praise. Purchased far, problem free. Connected it..called up Comcast..had them provision it. 10 minutes

Quickly adapts to whatever network device I have connected to it..only power it off for a few minutes when switching devices, so it "forgets" the MAC of the prior device. (I change routers frequently)
by Commander - 2006-07-08 01:57
Bought the modem, 2min setup. The neatest thing about this modem is the diagnostics panel it has. No flaws, none at all. Upgraded from a Toshiba.
by Tommy-Belgium - 2006-09-01 09:00
Does anybody has the login and pasword for the controlpanel?

by rey_1178 - 2006-11-23 16:17
by anonymous - 2006-12-05 16:40
Piece of Junk! Bought from Newegg and worked great right out of the box. Even doubled my download speed. After the 90 day warranty ran out from Newegg, I started having problems with dropped packets. After a couple of months of trying to figure out my problem (multiple calls to Comcast and Vonage), I finally decided to rent a modem (SA) and all problems immediately went away. So my newly purchased intermittent modem, that I ruled out during my troubleshooting actually failed me. Motorola says that they will be sending an SB5101. I sure hope it is an upgrade from the 5120 issues.
by pjb515 - 2007-06-20 21:56
Works great right out of the box, called Comcast to let them know I had just moved to Massachusetts and I wanted a broadband connection, they did their thing at their end and I was online within a few minutes. Incidentally, my previous modem was the Motorola SB5100, and it was also wikkid pissa! I still have it, but decided to treat myself since the 5100 is over two years old.
by anonymous - 2009-08-17 23:25
user: admin
pass: motorola
by Koil_01 - 2009-10-14 01:21
Does anyone know where I can get a custom firmware for this device? I'd like to open it up as a DNS for a friend.
by o0nE3ch0o - 2010-10-04 01:38
It`s not working for me via ethernet cable ...
by irek pl - 2019-01-17 15:05
I use this modem, provided by my cable TV, for 10 years without any problems, first through usb then through ethernet and your router.
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