Tried this on my xfinity account. It will bond all 8x downstream and 4x upstream channels, shows good signal (see pic, confirmed by xfinity advanced support) but not connect internet. xfinity said they no longer support this modem.
Looks like Cox may still support this. Best to contact Cox and check MAC ID (last pic) with them to confirm before purchasing. May also work with Spectrum and Time Warner. Please check in advance. No returns if your ISP has obsoleted the modem and purchased without checking.
google "cox certified cable modem" and CM400 is listed near the bottom under Speed Limited DOCSIS 3.0 Modems.
google "what is latest cm400 firmware v2.01.06" and it shows cox use firmware v2.01.06 which is on this modem (see pic)
Not making much money after shipping + ebay fees. Just posting this to keep useful things from going into the trash. Please check with ISP to confirm in advance.
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