Computer goes through restart loop before turning on?

[Bozzz]

When I turn my computer on, it runs for a couple of seconds, turns off, then turns back on. It does this for a random amount of time until finally i get to the BIOS. Once I see the BIOS screen, if I don't press F11 for the boot menu, the computer will bring up the screen asking me to plug in a hard drive, forcing me to turn off the computer and try again. Once I get into the boot menu, I choose the hard drive with Windows. Often while windows is loading the computer freezes then restarts, starting the whole thing over. The strange thing is, once I finally get the computer on and into the desktop, the computer runs perfectly. So my question is why is the computer so messed up when it turns on but then perfect once windows is loaded? I initially thought it was hardware issues, but I would think that would still affect the computer once windows is loaded. Now I really have no idea what it is. Any ideas?

 

[kushvyas]

Try Repair Windows by inserting the disk with which you installed the Operating System