Question PC switch won't start up but CPU, Drives, Power supply are working properly. (i think it's the front panel but idk)

[pcenthusiastakagamer28]

I've been trying to recover this old PC that i bought from my uncle I took it out the case to make sure what parts are in the tower (PC was broken but my uncle doesn't know exactly what). The power supply runs well, so as the CPU, it doesn't power up and I have NO FANS to hook up into the motherboard to see if the motherboard is working 100% properly. I think it has something to do with the front panel connectors, I've checked out the manual online and I've done everything correctly and it still didn't work. It had an Old GPU and Ram but it wasn't heating up so I have absolutely no idea if it works or not. What are the chances that it's just the front panel connectors? (also the screw driver trick doesn't work but it might have to do with my screw driver having a magnetic tip.)

 

[rgd1101]

how did you know the cpu and psu work?