I hope you can understand
My computer is quite old, and my parents won't buy a new one for me. I just want to know what's going wrong, when I try to press the power button, it turns on, but after a few seconds it turns off, then on, then off, and I can't stop it unless I stop the electricity. All the cables inside are connected, but there's one left, a connector I don't know how to explain, it's like a thing with 4 wires, a red one, 2 black ones and a yellow one. I can provide an image if needed, thanks.