Pc restarting itself

[rough quest]

its been about a month since i built my pc, today when i opened my pc and logged in it would keep on restarting itself any idea why this happens

[silver mountain]

full shutdown or like windows restarts itself?

[rough quest]

I turn on my pc, the asus logo appears, start loading and it crashes and restarts itself before the login screen of windows

Windows did try to repair itself but it did not help