Question Dead pc , wont turn on at all. IDK which part died.

Apr 6, 2020
It all started on monday when i couldnt turn on my pc in the morning, i pushed the power button and nothing happened, no lights, no fans, the only light was the rgb on my asus motherboard but that didnt mean anything. I thought maybe the power switch on my case gave out so i tried jumpstarting it with a screwdriver and nothing happened. I got to troubleshooting, stripped it to its barebones, put the mb on a cardboard box with the cpu ram and gpu installed and connected to power, tried jumping it again but this time i held the screwdriver for a couple seconds and it powered on with a display and everything. I put it back in the case, power button worked fine but i had to hold it down for a few seconds too. Used the pc for the rest of the day because i had homework to do and did some gaming to conclude the day.
NEXT day in the morning the same thing happens. click the button and no power at all, so i thought i had to hold it down for a few seconds again but this time it does not work. So i went back to troubleshooting, tested the PSU made sure it was outputting the proper voltage through the 24 pins on the ATX cable, i reset the CMOS, reseated every cable, tested with individual ram modules, even reinstalled the cpu and made sure there were no bent pins, gpu i dont know how to test it but if it was the gpu then the cpu fan will atleast twitch/spin right?

so should send back the motherboard or should i replace the PSU? i have no idea, was hoping someone could help since tech support just tell you scripted options or email you some copy pasted methods

i built this pc like 4 months ago and it was working fine until this very unfortunate moment of the year.

my specs are:
CPU ryzen 5 2600
MB asus b450f gaming
RAM Corsair vengeance LPX 4GB*2
SSD Teamgroup 512gb (windows)
HDD WD Blue 1TB (for windows storage and to boot linux PopOS)
CASE nzxt h510 (idk if this is useful)
PSU Seasonic FOCUS gx-550 80+gold (edit: forgot the psu)

i'd apreciate any recommendation, thanks!