Unplug everything from the motherboard, leave the cpu, memory, and power supply plugged in. If you get no post, reseat the CPU, try each stick of memory at a time, reset bios. Also, try a new PSU if you can. Your board is probably bad, if your PSU is turning on your fans, but there is no POST, your board probably got blown out, but there is a chance it is still just a bad power supply.