Do you see any LEDs lighting up on the motherboard when you turn on the PSU?
Also check the motherboard and see if any components on it (Capacitors, Inductors..) have melted or deformed?
From what you have explained(no fan spin), I think the problem lies with your motherboard.
However, here is a troubleshooting guide created by one of the forum members. try to work through it.http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems