Beginner with an used BeagleBoard

I'm try my first use of a BeagleBoard, but its an used boad, so I
don't know if it already has an embedded Linux or another SO.
All I have is an orange screen when I connect the BeagleBoard in a DVI
monitor, nothing more. I don't have a serial-RS232 cable so I hope I
can use it with the DVI screen.
How can I proceed?

if you are a beginner, use this:

I strongly suggest you use a serial cable to see the serial port
output in order to see boot loader and initialization messages.

Marco Casaroli