Asus PRIME x399-A, PC fails to power on

[Armand_Karlsen]

PC was running without problems last night and I put it to sleep mode as usual, but now the PC will not power on, whether by a keyboard press or the front panel power button on the case. I checked inside the PC and the motherboard itself, and there are no unplugged cables, nothing obviously burnt out, etc.

 

In the bottom corner of the motherboard, near the front panel header and SATA connectors, there is an LED marked "SB_PWR", and it is lit a solid, non-blinking orange whenever the PSU is plugged in to the mains. The PC will not turn on at all, whether I use the front panel power button, shorting the power switch pins on the system panel header, or presing the internal power button on the bottom edge of the motherboard near the Q-Code display. None of the 4 POST state LEDs in the top corner of the motherboard light up, and there is nothing on the Q-Code display. What is my next step; is there a way to bring this thing back to life?

[Armand_Karlsen]

Any ideas? I really hope I don't have to gut this build; it's not much more than a year old