MasterLi1's profile

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Saturday, February 14th, 2026 12:47 PM

netgear CAX80 error message

I have my own netgear CAX80 router/modem that i purchased and I am using Xfinity internet service.  This netgear unit was recommended by Xfinity.  I am receiving an error message on the netgear admin site that says my cable connection is Poor.  I am being told by Netgear folks my input speed is too fast coming into the Netgear unit.  Some people want me to add a splitter to the incoming line to cut the signal in half.  

This doesn't make sense to me.  Why would Xfinity suggest a router/modem that does not work properly with the incoming cable.  

Appreciate any help or insight.

Thanks.

Brian

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16 hours ago

...  Why would Xfinity suggest a router/modem that does not work properly with the incoming cable. ...

Like all modems and gateways the CAX80 requires the proper signal levels to operate correctly. If the incoming signal is too weak, too strong, or has too much noise, there will be problems no matter how well the device is working. 

If you want to troubleshoot this yourself, please see Internet Troubleshooting Tips. If you still need help, please post your Internet plan speed and the following information from your gateway (from http://192.168.100.1):

  • uptime
  • downstream: power levels, SNR (or MER), and error counts for all channels
  • upstream: power levels for all channels
  • complete event log, if available (Be sure to remove or blot out any MAC addresses. Forum security processing considers them "personal information" and may prevent the event log from posting if these are present.)

Copy and pasted text is preferred over images. Be aware that, if you post any images, your message will be made Private for a time, as all images must be approved by the Forum Moderators before the messages containing them become generally visible.

If you can't find the problem or you'd rather have Comcast take care of it and an employee does not respond to your message here, call them at the phone number on your bill or 1-800-Comcast, or use one of the options on https://www.xfinity.com/support/contact-us/. It's not likely they can fix the problem remotely. If not, insist they send a tech out to identify the cause and correct it.

If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit (approx $100) unless you have their Service Protection Plan ( https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device or anything outside your home you shouldn't be charged.

(edited)

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27.1K Messages

13 hours ago

... I am being told by Netgear folks my input speed is too fast coming into the Netgear unit. ...

That's not quite correct. "Input speed is too fast" isn't really a thing. The problem is that the downstream power levels are too high. As stated in the Troubleshooting Tips article, downstream power levels for a gateway should be between -7dBmV and +7dBmV. All your downstream channel power levels are out of spec (too high). 

Also downstream SNR values should be above 35dB, so the values for channels 6 and 7 are out of spec as well (too low). 

Adding 6dB of attenuation should correct the downstream power levels, but probably won't help the out-of-spec SNR values. It might be best to have a premise tech take a look at these problems. 

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