PSU Brand: NMB
Transistor Q20 (BUX86P) was broken, it was getting hot as I look at the board. There was glue arround Q20 & R201 that came very very hard.
My guess is that because of the glue the pins of Q20 have been pulled out of the solder joints and caused even more heat.
Removed Q20, R201 and the glue, and replaced the transistor with a BUX87P, because I couldn’t find the BUX86P.
Tested the PSU and it works again!