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No ip address when computer is plugged into modem

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Frequent Visitor

No ip address when computer is plugged into modem

I recently upgraded to gigabit service and I have not been able to get more than 250mbps on any device in my house. A technician came today and said the speed is good at the modem and suggested it may be my router. I am using a netgear nighthawk cm1200 modem. The problem I am having is that I can't test this for myself. My router will pull an ip address from the modem, but I do not get an address when I plug my computer directly into the modem. I don't really have a problem buying a new router if that really is the problem, but I would like to verify that before spending anymore money. Can anyone suggest what to do in this situation?
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Expert

Re: No ip address when computer is plugged into modem

FWIW, you need to power cycle/re-boot the modem each and every time that you change the device that is being directly connected to it in order for that device to be able to get an internet connection /IP addy.




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Frequent Visitor

Re: No ip address when computer is plugged into modem

Thanks. I actually figured that out shortly after posting. After getting an ip address I still only get ~320mbps on speedtest.net and 510mbps on xfinity speed test. What else could I look at to figure out what is going on?
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Expert

Re: No ip address when computer is plugged into modem

https://forums.xfinity.com/t5/Your-Home-Network/Gigabit-speed-troubleshooting-video/m-p/3310454#M316...



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We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!