this review be two-part , first to Amazon as provider and second , to the product itself . note that the `` star rating '' be for the product and not for the provider of the product -lrb- in this case , Amazon -rrb- . this be a quick review , as I just want to let Amazon , and hopefully , motorollum about the product that I buy . Amazon : First of all , Amazon do a amazing job send and ship the product . it be very fast , ship the day i order it and arrive two day after . thanks Amazon !!! product : Motorola SURFboard sb6121 I purchase this against my gut feeling vs the older sibling sb6120 . while I understand that performance wise , it be -lrb- technically -rrb- similar . after read many review , and check spec , I find out that the sb6121 and sb6120 use the same firmware . however , what really entice I to get this be the fact that it be `` greener '' . however , I be extremely disappoint with the product . it come brand new , seal , with all the proper documentation and part . but the modem will not stay `` on '' and stable for more than 1 minute . the modem will boot up , sync for a few second and then will reboot again . my line be pretty clean , use my current Cisco DPC3000 cable modem , I get -1.2 db on downstream power , and 37 snr on downstream on all 4 channel , and with 49.5 db on upstream power . my Cisco modem be stable , no reboot nor reset , but I be pay $ 7\/mo so this have to go . unfortunately , Motorolla can not even stay still long enough for I to activate the modem at Comcast . the modem will boot up , and I 'll be able to load the Comcast activation page , and then it will suddenly reboot . I can not get past the page where I need to enter my account number because the modem would have reboot by then . call Comcast prove futile as well , as they say that they can not get anything useful from they monitoring end . while they see activity , it will quickly go out and that be because the modem keep reboot and loose sync . it may be a faulty power brick , or a faulty modem . either way , I do not like a faulty brand new equipment . I pay good money and I expect the product to perform as expect . contact Amazon for a replacement , here 's hope it will arrive as fast as the original order . if it fail again , I will not be waste Amazon 's stock anymore and just replace it with the older -lrb- and cheaper -rrb- sb6120 version .