Hi I have a desktop computer and it have a problem

Question

Hi I have a desktop computer and it have a problem

since near to 1 year

Explain the problem :

The computer has been off for 10 hours - now i want to turn it on - but When I press the start button, it trying to start for 1 second And then it goes off - it stays off for 2 seconds - then trying to start for 1 second - ...

This cycle lasts up to four times😐

after four times , the computer turns on

i changed motherboard
but both of old and new motherboards have this problem!
This indicates that the motherboard is not a problem

I decided to change power of pc

The problem was not resolved with four different power supplies!

Apparently the name of this problem is "bootloop"

anyone have any idea to solve this problem?