Connect it up and let it fully sync with the system. If you don't see the Self Registration Page (the Walled Garden) when you open the browser of a computer connected to the modem then you will need to call in and tell them that you want to have a new modem provisioned for service. Have the make, model, serial number, and the HFC MAC address handy when you call. If there is a newer firmware available for it on the CMTS / system, it will be pushed automatically.
Sorry for the echo ExoticFish
. Didn't see your reply before I posted.