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The Internet should add convenience, not headaches. From step-by-step instructions to helpful tips, we'll help you install your equipment, troubleshoot problems, and get the most out of your online experience – minus the migraine.

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Troubleshooting Slow Internet Speeds by Checking Modem Health

Last Updated: Tue, 28 Aug 2012 > Related Articles

81 rated this


Learn to test your modem for slow speeds.



You are able to get on line, but may have intermittent connection problems. You may also have slow download speeds, issues with web pages opening slowly, and a slow transfer rate when downloading files. 

Troubleshooting Steps

It is important to make sure: 

  • Your modem will work on the Cox network
  • You have the right type of modem for your Internet package
  • Your modem is working properly 

The steps below will help you to troubleshoot and resolve Internet speed issues, which may be caused by your modem. 


Isolate your modem and test your speed.

If you are connecting through a wired or wireless network, try connecting your modem directly to your computer. Then, run a speed test. If you are still not getting the proper speed for your Internet package, your modem may be the cause of the problem.

If you are not connecting to the Internet through a network in your home, we still recommend using the remaining troubleshooting steps. This will ensure your modem is not the cause of your speed complications. 


Check to make sure Cox supports your modem.

The best way to tell what kind of modem you have is simply to look at the modem itself. The manufacturer name and model number are usually printed clearly on the modem. You may also check the user’s guide if you still have it.

After you determine the manufacturer and the model number, you can search for your modem using your favorite Internet search engine, like Google or Bing, to find out details on your modem type and use.

Then, you can find out if your modem will work on the Cox network by checking our compatible modems list


Check to make sure you have the right modem for your Internet package.

All cable modems use a standard for hardware and software called DOCSIS. The version of DOCSIS on a modem determines the maximum speed. Refer to choosing the right cable modem to make sure the modem you have will work with your Internet package. 


Check to make sure your modem is not damaged in some way.

Generally, modems do not have an expiration date. Placing your modem in an area free of clutter and checking to make sure the connections are not loose will improve its life span. With constant use, though, it is possible for modems to stop working properly after a while.

Does your modem have any of the following symptoms?

  • Slow speeds all the time
  • Very hot to touch or smoking
  • Restarts constantly
  • Does not power on when plugged in
  • Purchased more than five years ago

If your modem has one or more of the issues listed above, buying a new modem may improve your Internet speed and connection stability. You can purchase a modem directly from Cox or from any major electronics retailer.


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