I recently bought a new processor, cpu cooler, case and motherboard after all these were put in the case and abit of cable management this happens.
When I press the power button the system starts, after 15 seconds it powers off and then about 5 seconds later auto powers on. Once it automatically powers itself back on it remains on. Through all this there is no video signal. The cpu fans, case fans and gpu fans are all working. I really don't know where to start to fix this problem, my system looks like this.
Motherboard = Asus P8P67 Pro B3 Revision
PSU = Corsair TX 750w
CPU = Intel I5 2500k
CPU cooler = Noctua NH-D14
Ram = x2 Rendition 2GB DDR 3
GPU = GeForce GTX 580