Hi there,
I ordered the Best hot air station yesterday. The fact is that i got 2 Xbox One X to repair, one was fairly simple, Retimer IC to replace, job done, console working again, then i got the second one which turns on and within a second goes off with the chime sound of the poweron working.
I haven’t found any “working” diagnosis out on the web, neither in this forum besides someone saying in this thread : Xbox One X - Ding and light when power button pressed, turns off after a few seconds and also in this one : Another One X that turns off then turns off (Partial power) with pictures! that this issue might be related to either APU or soutbridge issue. I tried to at least reflow the southbridge, to give a start somewhere let’s say, and after pre-heating the back and using my Aoyue for 15min max air flow and max temperature, the SB wouldn’t move a bit. I gave up and ordered the Best 
By the way, this Xbox One X turning on then off is not something that people talk about much on the web 