Custom Build pc wont start

[ferhan96]

I've just built my first custom gaming pc, but I'm having a few problems. I'm fairly certain I have installed it all correctly, but it wont boot when I press the power button. The power button on the motherboard has a red light when I turn on the power supply, and when I press this, the other components turn on. However, the CPU LED also appears red, and the motherboard power button also stays red.

Here is a list of the parts:
Motherboard: ASUS 79Z-PRO
Case: Cooler Master HAF 912
Power Supply: XFX 550 Watts
CPU: Intel Core i5-4690k
GPU: EVGA GeForce GTX 960 SCC ACX 2GB
RAM: Crucial Ballistic Sport 8GB
HDD: WD Blue 1 TB

 

[alexoiu]

Is the 8 pin power cable connected to the motherboard? Is the CPU fan spinning when starting the board?

 

[ferhan96]

Is the 8 pin power cable connected to the motherboard? Is the CPU fan spinning when starting the board?

Yes, the power cable is connected to the motherboard, as is the fan, which spins when I start the board.

 

[alexoiu]

What are the last 4 digits on a sticker like http://www.guru3d.com/miraserver/images/2011/990fx-sabertooth/IMG_4499.jpg ?