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Internet speed drop

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Internet speed drop

We just upgraded to the 1000mbps plan as we have multiple people in the house using alot of gaming, video streaming etc... When I first connected to the internet on my pc and run the speed test on the xfinity site as well as ookla I got around 930 ish download and 40 upload. Then a couple hours later like 1hour 30min - 2 hours I was checking the speeds again and this time the download was 20-30 download and upload was cut in half at 20. I quickly realized that reseting the modem fixed the speeds and after the reset I got around 800-900 ish download and 40 upload. But then like clock work 1hour and a half to 2 hours later it was back down at 20 mbps dowload. We have reset the modem and router several times now... every time it fixes the issue but then proceeds to go back down to 20 download like its on a schedule. We have called the manufactuers of the modem and router and they seem to be clueless on this issue. Comcasts only answer was to schedule a tech appointment. So I guess im just wondering if this is a normal thing that can happen. Aswell as if anyone has any clue what is causing this issue, the modem, router, or is it on the Isp's end of things. We have our devices plugged into the router which is connected to port 1 on the modem. The router is the only thing connected to the modem. According to netgear this modem is only used as a middleman for the isp and the router... also when we tested the speeds we were doing so via ethernet cable as well as wirelessly and on multiple different devices. The pcs via ethernet obviously were seeing the higher speeds on ookla compared to the consoles and phones. And on the xfinity speed test it was 900-940 everytime right after reset then 20-30 a couple hours later. As I stated earlier we do have a technician coming out tommarow but was just curious if any one had any info on this problem. Thanks I will also give an update on the tech appointment for anyone wondering on how that goes. 


Here are the modem and router we are using by the way -


Modem- Netgear Nighthawk Cable Modem CM1200


Router- Asus Wireless Router RT-AC3100






Re: Internet speed drop

For a test, does a computer hardwired directly to the CM1200 cable modem (no router in the mix) have the same problem ? You'll need to power cycle the CM1200 when you make the change, and then again when you reinstall the router.

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