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Home » What should I buy? Is it on Amazon? » A Cable Modem of Your Own

For those of you not willing to pay Comcast $7 a month for a used and obsolete cable modem, I suggest buying your own.
In general, check with your cable provider for the list of appropriate models, but this one is on the Comcast list (as of Nov 2013, anyway), and works much better for me than what you get as a rental:

Motorola SB-6121