If the old modem is not DOCSYS 2.x it can't handle the higher speed. My speed jumped when I upgraded the modem.
I was on phone all morning with comcast do speed tests and reconfiguring my modem and I am still only getting speeds like 4.5 download and upload when I should have 15mb service. I have 4 pc's all hardwired to my modem and I run a mmorpg game on several of them and they disconnect everyday several times per day. Comcast is sending a new modem after I fought it out with them, but how can they charge you for additional speed when its not even close?
I have a linksysy router, all pc's are hardwired except laptop. I will try a new router if needed and new ethernet cables but once all that is replaced, what do I do to get better speeds? I dont think the problem lies with the router or the modem and I hate giving comcast my money for a service that the 'slowskies' would enjoy.

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