An arris modem can be used with this Router even if your modem is bundled with a router or phone. But in order to get better wireless performance, you will need to get a better performing router like this linksys, but first you will need to turn off the router portion of your bundled modem to install your new router. To do this you would first need contact your internet provider to help you thru this task. Most ISP's will walk you through the resetting and reinstalling of your existing modem without the Router portion. This option of resetting and re-configuring the modem is necessary before you can use your own router. During this resetting process your modem memory will be deleted and will be set to original factory specks and your modem should perform like knew, unless there is something wrong with your equipment. The modem performs better and lasts longer when you use a separate router. (Some) manufacturers use cheaper components when bundling to help keep costs down. This of course may not always be the case but bundled modems do run hotter. Be sure to set your modem on hardwood, tile or cardboard or anything else that will help keep the static electricity from from undermining your equipment.