There's a lot to go over from connecting directly to the Comcast modem to scanning for malware to trying another DNS.
I've had Comcast and for me it was just fine. However you do encounter folk that have one PC and will need support beyond the usual.
Bob
Comcast when tested says it is going through fast, but this is just not true. The web sites dont show, then you hit the retry an it works after 10 times and 3 or 6 minutes.

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