Computer won't start every other time

[Stu Pidasso]

If you press the power on button on the front of the computer it will start. The computer then works normally. Next time you go to start the computer it will kick on for a couple of seconds and then shut down(but won't even get to the POST). Hit the power button again and it starts up normally. Its like clock work....it happens every other time. Power supply was replaced and the problem still exist.

Any help appreciated

Stu