Computer wont turn on after crash

Hey,

I have just installed a new i5-750, with 4GB of Crucial Ballisitix PC3-12800, Akasa Nero S and a Gigabyte GA-P55-USB3 motherboard (the rest of my specs are in my sig).

This morning it was stable at 3.5Ghz. I then tried to run the CPU at 3.8GHz. After running Prime for 30 mins everything was fine, my temps were in the high 60's to low 70's but then it just crashed. I wasn't looking at my monitor at the time so I dont know why this was.

Now when I try to turn it back on nothing happens. The lights flash on the motherboard then go dead, the case fans dont spin up, the Heatsink fan doesn't spin, nor does the GPU fan or the HDD. To me this suggest the PSU is blown, however the PSU fan is spinning.

I really need some help trouble shooting this problem. I have checked the CPU and there is no sigh of damage as well as the socket, which also shows no sign of damage.

Thanks