I have Earthlink internet cable. and i am planing to get my own modem. I am planing to get Motorola with the New Docsis technology 3.0 SB6120 extreme cable modem or SBG6580 extreme wireless cable modem
do you think Earthlink will activate my new modem ???? PS: Earthlink use Timewarner cables
Earthlink has nothing to do with it. TW probablly won't let you use the 6120 (because they've phased out support for it.) In most areas, they won't let you use your own D3 modem.
It really won't matter as Earthlink doesn't charge you anything for the modem.