Overscan and HDMI Modes

Note: This note was originally in the Raspberry Pi 2/3: Chromium in Kiosk mode post.

In some cases the image may not fill the screen.

The overscan setting below can help, as well as forcing certain HDMI modes as document [here](From https://www.raspberrypi.org/documentation/configuration/config-txt/README.md) and here.

Edit /boot/config.txt to change these settings, for example hdmi_mode=16
is 1080p@60Hz when hdmi_group=1 (CEA).

disable_overscan=1
hdmi_group=1
hdmi_mode=16

Before:

Before

After:

After

The difference may be subtle here.