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My ISP is Comcast and recently I have moved away from the OEM gateway they provided. I bought the DOCSIS S33v2 Surfboard to replace it, but I am not able to get anything near the advertised 1Gbps download and 200mpbs upload speeds. On the Comcast gateway I can get 900mpbs download and 200mpbs upload, with the Surfboard only 200mpbs download and 5mpbs upload.
I am not sure if there is a misconfiguration on my end, or on the end of Comcast. I have already called Comcast and they said they would fix it, no difference hours later. Is there anything I can do to troubleshoot the slow internet speed on the modem myself?