I’m having the same problem. I tried replacing my optical drive but in the process I ripped the sensor ribbon. I’m waiting for a new one to come but my Xbox has no power and the light is orange. I’ve stripped it to the bare mother board. I’m not got going to diagnose anymore until I get the part. But I’m thinking it’s a NCP 4204. That’s the power control IC chip. I would check that and the mosfets. Definitely make sure the board is getting power. Everyone cross there fingers and try it out. I’m not saying remove or destroy your board just do some tests.