I have tried both the SB6120 and the SB6121 and the signal levels and speeds were the same on both. The SB6121 is a little smaller than the SB6120 but runs much warmer than the SB6120. Looks like they tried to cram too much hardware into too small of a space. My SB6121 did not come with the power save button (it#39;s listed as an optional feature), so about the only difference between the two models is the design. Both the SB6120 and the SB6121 use the same firmware: labeled SB612X. So unless
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Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem review
