Question Bought a new gpu, used the pc just fine and suddenly pc just turned off and cant be turned on

Feb 19, 2019
So basically, i bought a new gpu (rx 570 4gb) and placed it in my pc, everything went smoothly for about an hour, but suddenly my pc just turned off, i was like ok this is maybe just a loose cable or something, i checked everything and tried to turn it back on but it didnt work, im guessing that my psu couldnt handle my gpu? and just broke or something my psu is this i used an adaptor that transports my 6 pin to 6+2 or 8 pin, tried to turn on my pc with my old gpu (gtx 750 ti) and it didnt work either, im 90 percent certain that its the psu but im not the biggest tech guy so please help me out :)
My full specs:
cpu: i5 4460
gpu: Rx 570 4gb
mb: Gigabyte h81m-s2h
psu: Modecom feel 500 w
8 gb of ram