If you're unsure what box model you have, go through the following steps:
Open the Main Menu
From Information & Reset select Device Information
If you're not able to get into settings, you will be able to find the box model printed on the back or on a sticker on the bottom of the box.
*Depending on your box model, Settings will be on the last tab on the Main Menu or in a cog in the top right corner of the screen. You can get to the cog by pressing Up after opening the Main Menu.