When I Turn My Computer On It Shuts Off After A Split-Second. Please Help!

[blockhead12]

I built my computer a few months ago and I had everything working up until now. I bought a new CPU fan a couple days ago and just now had the time to install it. I unplugged all of the cables to my motherboard because I thought I was going to have to take it out in order to install the fan, but I then realized my case had an opening to the back of the CPU so I didn't need to. I then put in the fan being careful not to touch the CPU or motherboard. I then plugged everything back in and turned on my computer but it only turned on for a second and then right back off. I checked every fan and they all turned on and so did the LED's on my motherboard. I'm not sure what could have happened from me putting the fan in but if anyone know's what might be the problem please let me know.

Specs:
Motherboard - Asus P8Z77-V LK
Graphics Card - GeForce GTX 760 4GB
CPU - Intel i5 3570K LGA 1155
PSU - Corsair CX500

 

[NiCoM]

Make sure the two cables from your power supply are inserted all the way in your motherboard, had the same experience when the 24-pin connector in my motherboard wasnt inserted properly

 

[blockhead12]

Make sure the two cables from your power supply are inserted all the way in your motherboard, had the same experience when the 24-pin connector in my motherboard wasnt inserted properly

I checked all the wires and still when I turn it on it turns right back off. One thing I did notice was that one of the case fans plugged into the motherboard wan't turning on.

 

[NiCoM]

Make sure the new cpu fan is installed properly, if it isn't and the cpu goes really hot it would turn itself off. You should also check if its the fan or the connector which is broken to the non-working fan. If its the connector you might have damaged your board under install. (Simply connect another fan to the connector to check this)

I can see two things which could be the reason:
1: Something is not installed properly
2: Your motherboard is broken

You should call ASUS technical support to see if they have any knowledge about this problem.