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Motorola SURFboard SB6121 DOCSIS 3.0 Cable Modem

Posted by
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Message 1 of 7
21,116 Views

I just got comcast high speed internet and i didnt want to pay $7 a month for the lease modem so i bought the SB6121 from newegg. However when try to activate the modem online the modem always reboots itself and i can activate. i honestly dont know if this is the internet's issue or the modems issue.

 

Any helpful tips you guys can spare me?

If the problem is the modem can you guys reccomend another one that a decent price?

 

-Eric (Jimmy is my dad's name)

6 REPLIES
Posted by
Cable Expert

Message 2 of 7
21,115 Views

We need more information please:

- Post your upstream and downstream signal levels. Click the link or type: http://192.168.100.1 into your browser. We are interested in your power levels (dBmV) and your Signal to Noise Ratio (SNR). You may also want to contact Comcast and ask for your upstream SNR (uSNR) and receive level.

- Post your modem’s error logs.
- Post the make and model of your modem.
- Post the make and model of your router if you have one.
- Let us know if you contacted Comcast or had a tech visit.
- Let us know what the lights on your modem are doing when you are having problems.




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Posted by
Bronze Problem Solver

Message 3 of 7
21,111 Views

Did the modem ever work? Did you call CC and ask them to set it up on your account? The computer set up process does not always work. call them tell them you want to set up your customer owned modem.

Posted by
Connection Expert

Message 4 of 7
21,101 Views

Jim721 wrote:

Did the modem ever work? Did you call CC and ask them to set it up on your account? The computer set up process does not always work. call them tell them you want to set up your customer owned modem.


FWIW, If the modem is not in "block sync" mode they will not be able to see it or provision it for service.




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I am not a Comcast employee, I am a paying customer just like you!
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We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee. I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help.
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Posted by
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Message 5 of 7
19,600 Views

I am having the same problem.  On my second sb6121 so suspecting it is comcast.

Posted by
New Poster

Message 6 of 7
19,572 Views

I had the same issue.  You actaully have to call Comcast and manually give them your modem's info. The web provisioning will not work. 

Posted by
Connection Expert

Message 7 of 7
3,186 Views