Question PC suddenly turns off after posting bios screen

Jul 11, 2022
Hello. I have pc with specs: rx 480 8GB, atx-800w PSU, z170 motherboard, 8GB ram 2133mhz, i7 7700 cpu.

When I am turning it on, it is posting bios, I can even enter bios and after posting bios screen it just turns off. I have not seen even a single post about this problem, am I the one who has this kind of problem? Led lights are working and everything, pc is not getting hot, it starts to post like it usually would hut then suddenly shuts off.