Question about Arris SB5100 SURFboard DOCSIS 2.0 Cable Modem (50120900100)

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Motorola 5120 Surfboard

I had to wipe my whole computer and re-install everything. My modem wont work. It says it cant find the motorola 5120. How can I make it work?

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Re: Motorola 5120 Surfboard

Sounds like the driver was erased during the re-install.  Use another computer, go to '', then downloads, find your modem and download the driver.  I'd give the specific address but its not hard to find.

Posted on Mar 14, 2009

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Re: Motorola 5120 Surfboard

Yes it can happen after a reinstall.. You will need to go into the computer ie take the back off. Pull the modem out and put it back in in another slot exact to the one you pulled it out of. Try it again it will no doubt read this time.. It can only be done this way if you try to manually install a moderm it will load the standard one NOT your Modem. Goodluck!

Posted on Sep 09, 2007

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If the modem is already registered to your ISP then you can plug the modem to your computer using an Ethernet cable (CAT5) to your computer's ethernet port and to the modem's port as well.

If you want to use the USB cable then you need to install the drivers for it. You may go to motorola website and type in the model number of your modem to get and download the drivers.

Though, I suggest that you use the Ethernet connection instead.

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