It’s not just about what the modem can support, it’s more about how much bandwidth the ISP allocates to each channel, as they still have to support a ton of people within those same bands.

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Arris’s SB6141 modem is a docsis 3.0 modem w/ 8 downstream channels X 4 upstream channels. At the time, the XFINITY REP was sorta correct in trashing the SB6141 modem because yes, it will work...but in terms of other modems on the market, your SB6141 is not as good as others! Your “up to 200 Mbps” plan should have a Docsis 3.0 modem w/ @ minimum 24 downstream channels X 8 upstream channels. Ideally for future proofing purposes; I’d recommend buying a Docsis 3.1 modem which is the latest greatest standard; is 32 downstream X 8 upstream channels. More on reddit.com

Modems are simple math really. DOCSIS 3.0 allowed for channel bonding. Actual speed is around 38mbps per channel after overhead for downstream DOCSIS channels. Modems bond 4, 8, 16, 24 or 32 channels down. So yes, a 6141 bonds up to 8 channels, but that is SHARED between you and everyone else on the "node" (used loosely). So the maximum speed you could ever see is right around 304mbps if you saturated all 8 channels and no one else was home. A 16 channel modem would mean you downloading at fullspeed would still saturate 50% of the total bandwidth on the node. Still pretty scary! Realistically with a 300mbps service level you should consider the modems with the most amount of channels. The issue I would look out for is the latency bug most all 32 channel modems have (still isn't fixed as per DSLReports forums) - see: https://www.theregister.co.uk/2016/12/03/intel_puma_chipset_firmware_fix/ More on reddit.com

The modem does not care how many users are on your network. The 6141 is capable of 100 Mbps w/o a problem. It's possible you have signal issues or the modem itself is failing. You can see your modem signal levels by pointing your browser to http://192.168.100.1/. You can speak to Spectrum to see if your signal levels meet specifications for their system.

Most likely your choices will be to either have a tech visit or buy a new modem. If you have signal issues, a new modem won't solve your problem. Either way, it's probably time to replace the 6141 anyhow.

If you decide to buy a new modem, consider a DOCSIS 3.1 device as it is the newer standard for cable modems. This will give your modem a longer life cycle and will be a better value over the long term.

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