I have an MCIMX7SABRE board. I inserted the sd card that came with it and powered it on. A monitor is plugged into the HDMI port and I can see the monitor signal light is lit, but the screen is black.The green power led is lit. The yellow led next to the ethernet port is lit, but I get nothing on the screen. I tried a different monitor, but still nothing. I tried plugging in a windows laptop with putty to the debug port. The two ports show up in device manager as COM3/COM4, but when I set putty to COM3 with 115200-8n1 and click open I get nothing. I checked the SD card to see if it really contains an OS and it does.
Is the board bad, or is there something I've overlooked?