Question pc worked fine took apart for fun and now wont turn on

[plshelpwithpcpls]

IDK if power supply is ok i did quite heavily thump it on the floor by accident and also did it on carpet but wore a wrist band thingy this is the first pc i built and i was using free cheats (never again after this) and turned on my pc after getting back from my dads i tried to login and i didnt work i got hacked and they changed my windows password and took my windows key but thats besides the point i took it apart for fun because i was bored i put it back toghether and i pressed the power button... nothing i took it apart again and it still didnt work so im currently replacing the motherboard and power supply, but my usb ports still give off power??? im just very confused and dont know what to do

 

[rgd1101]

full system spec? include brand and model of the psu

 

[plshelpwithpcpls]

ryzen 5 2600
16gb of corsair vengance ram
16gb of g.skill ram
evga 850w psu
b450 pro4
rx 580 8gb
samsung m.2 500gb
2 barracuda 2tb hard drives
cooler master aio

 

[plshelpwithpcpls]

i also used a screwdriver to try and start the mb and didnt work

 

[rgd1101]

start with the min.
cpu, 1 stick of ram, gpu, 1 ssd

is it a modular psu? test the end on the psu?

 

[plshelpwithpcpls]

im not at my moms rn ill def try but i have no thermal paste and i already ordered a new psu and mb ty for the help though

 

[rgd1101]

wait, you took the cpu out?

 

[plshelpwithpcpls]

wait, you took the cpu out?

while the computer was off yea and i got cotton ball thing on it so i took a tooth brush and some rubbing alc and rubbed it off