The first time you select a 1080p program on screen, your receiver will automatically perform a resolution test to check for the correct TV resolution. Your TV must be connected to your receiver with an HDMI cable.
If your TV does not support 1080p, the receiver will automatically display the program in the highest resolution supported by your TV. In this case, you'll see an onscreen display that reads, "Sorry, your TV does not support DIRECTV's 1080p broadcast". The receiver will determine the highest TV resolution available via the HDMI data or from the manually set TV resolutions settings from the System Setup menu. Additionally, when the receiver is in 1080p mode, the 720 and 1080 LED lights on the front of the receiver will be lit simultaneously.
If your receiver is connected via component cables rather than an HDMI cable, it will automatically show the 1080p programming in the highest resolution supported by your television. You'll see the following message on your screen: "This program is available in 1080p broadcast. To check if your TV supports this resolution, you will need to use an HDMI cable to connect your TV to this receiver."