Hello all,
(I am just getting into electronics repair so excuse the noobness

)
I have an Asrock B450 Pro 4 motherboard which doesn't power on. I have access to the Broadview file.
I have checked that the PSU is working. I have the 5V standby on pin 9 and the 5V PSON# on pin 16. When I short the pin 16 and the ground I see the fan running and other voltages as well.
I have removed everything from the motherboard except the CPU fan and have only connected the 24pin power from the PSU. I have not connected the 12V power from the PSU...