Port 80 display
A two-digit display found on some motherboards that display the port 80 code sent by the BIOS (basic input/output system) when the computer does not pass POST (power-on self-test). These displays are helpful for diagnosing what in a computer may be preventing it from properly booting. For motherboards that do not have a port 80 display listening to the beep code helps identify the error.
A technician or someone who fixes computers may also use a POST card, which has a port 80 display to display the port 80 code. The picture shows an example of a POST card that plugs into the PCI (peripheral component interconnect) slot. It identifies the code sent by the BIOS on the port 80 display.
A POST card may also be called a POST reader, checkpoint card, and port 80h card.