no signal ,black screen, fan is going really fast

So recently my Xbox had no signal and black screen so after researching I said to !&&* with it I opened up my Xbox it was not under warranty so what can I lose noticed that my hard drive was making a funny noise I bought a new hard drive still had a black screen and no signal but now my fan kinda goes berserk and starts going really really fast i don’t know what it could be maybe the thermal paste? ill drop a pic of it so now i’m thinking either retimer or power supply im gonna test tomorrow with a multimeter but for now anyone got a clue why my fan is going berserk