worked before

So I built my pc back in November of 2019 and have had no issues with it up until today where now its suddenly no longer booting anymore, when I hit the power button, the cpu/gpu/case fans all spin up and I get the usual 1 short beep like normal but nothing happens after that, no additional beep...

earlier today i was using my pc, the case fans were quiet and controlled by msi afterburner, i tried out oc setting in the msi gaming app and it messed up my pc in an constant reboot where it tried to repair too but failed to do it. after that i had to flash the bios with flashback+ and the i...