PC won't turn on- Mobo or PSU????

Hi everyone, need some help for my sad PC.

My system has been rock solid for 12 months and running like a dream with not a single drama or BSOD. No hardware changes in the last 4 months (installed an SSD for my OS) and the only software changes have been a couple of new games installed.

I went to turn it on today only to find a big lot of nothing doing. No fans run and no lights on the front power and hdd LEDs. I opened the case and my MOBO power and reset buttons light up but do nothing when I hit the mobo power button either. I have tried all the usual things, made sure my power board hadn't had a surge, changes the power cable for a brand new one, and have gutted and rebuilt the PC to rule out any shorting of the mobo, RAM or graphics card issues and that everything was plugged in good and snug. Even tried it with nothing but the mobo and CPU to see if I could get it to post or at least some beeps, I get nothing at all just the power and reset buttons on the Mobo lighting up to taunt me.

I'm guessing the issue is going to be either the Mobo or the PSU that has had a tantrum. I don't have another PC to test either of them, so anyone got any other ideas that can help me either get my PC back up or at least identify which is the problem child. I'm no expert but can follow instructions very well.

I built it 12 months ago and have not had any issues at all so not sure why it has died so suddenly.... So any help would be much appreciated.

System specs:
Asus P8Z68 deluxe/gen3
i5 3570k
16gb RAM - G-skill cybersniper
120gb SSD
A couple of other HDD's
On Win 7

Thanks

 

I just had an issue with one and believe or not the culprit was the switch in the case I did change the power supply, cable and double check everything, since I had a band new case I change it and voila! Now my friend have a brand new case. Let us know.