The specs of the cable modem says the interface supports gig download speed, but the modem does not supports it. The modem has a 24X8 channel bonding, but in order to have a gig download you need the 32X8 channel bonding. I ahd the same issue when I ditched my TV and phone from my internet package and updated my internet connection to a gig. My modem was an SVG2482AC when I had TV and phone, but after the line upgrade I needed to upgrade my modem to an SB8200 to get full support for a gig connection to the internet. I hope this answers to your question.
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