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stevehifi2003's avatar
New Contributor
4 years ago

new Arris sb8200 - issues with downstream (no blue light) with gigablast

Hi There,

Wondering if you can help me, I just got an Arris SB8200 modem today and ordered Gigablast service. 

My lights are all green (no blue at all). I am in orange county, california (92630). I connect to Cox orange county server

and my download speeds range from 300-600Mbps. Upstream is consistent at 35-40Mbps.

WIFI speed is not consistent on downstream (100-250Mbps)

So I'm not getting advertised 940Mbps and the blue light (which Arris documentation states indicates high speed DOCSIS 3.1

connection is NOT ON - still green.

My older Docsis 3.0 modem and 200Mbps service didn't have this problem. Always consistent downstream for both LAN and WIFI.

Any ideas on what the problem could be?



8 Replies

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  • Hello Steve,

    Have you accessed the Web Manager of your SB8200 to view and monitor the operational status? Please type the default LAN Ip address,, in the address bar and press Enter. You may check the Status Screen to see if there are any obvious signs there. You may email us for support at with the status screen, your complete address, and first and last name of the account holder. We will be able to look into this issue you're seeing with speed loss.

    Cox Forum Support Moderator
    • stevehifi2003's avatar
      New Contributor

      Yes nothing obvious wrong with the modem when I go to the status screen. Am I supposed to see a blue light on the modem or not? I've hit speeds up to 700Mbps (almost at 940), does this mean I'm still in docsis 3.0 mode or not?

      • BrianM's avatar
        The light should turn blue to indicate that the OFDM channel is connected and that the modem is running in 3.1 mode. I just checked your modem and it doesn't look to be connecting to that channel currently, this is likely a signal issue. Some of your downstream channels are a bit low and some of the upstream channels are a bit higher than normal. Make sure everything is connected securely and bypass any possible splitters. If you still don't see it turn blue afterwards we will likely need a technician out to investigate.

        Cox Support Forum Moderator
  • Peterockinit's avatar
    New Contributor III

    Hey there, I am having the same issue as you. New sb8200 (2 weeks old), I ordered gigablast in Las Vegas and am getting no docsis 3.1 on my upstream. After asking the 7 different techs that came out over the last two weeks, everyone answered with a "I don't know why"

    Just curious, where did you order? I am wondering if we have a faulty batch of modems?

    • stevehifi2003's avatar
      New Contributor

      I ordered the modem through Amazon. I got another to see if it's a lemon and will try

      • Peterockinit's avatar
        New Contributor III

        I got mine on Amazon also.

        On your modem logs, are you getting dynamic range window violation errors and commanded power exceeds top of the drw errors?