I just put together a new ITX build and when powered on the fans blow at full speed for a variable amount of time between 3 and 5 seconds after which the computer restarts with no POST screen (continually). I have noticed that it usually reboots the moment the lights on my Corsair H80i pump turn on. Also, I don't think my motherboard or case came with a POST speaker so I can only go by the splash screen.
CPU: Intel i5-3570k
Motherboard: Asrock Z77E-ITX
RAM: GeIL 2x4GB DDR3 1600MHz (9-9-9-28)
CPU cooler: Corsair H80i
Video Card: EVGA Geforce 660
Power Supply: Antec High Current Gamer 520Watts
Hard drive: Samsung 840 250GB
Case: Bitfenix Prodigy Midnight Black
I have tried using a different (definitely working) PSU and swapping/taking out the RAM.
I also attempted to get it to POST by installing nothing but the CPU, RAM and motherboard but it still has the restarting problem. There is a CMOS button on the IO Panel that glows red while the PC is on, pressing it doesn't seem to make a difference. Nothing shows up on the monitor regardless of which port I plug it into.