check ur cpu fan is running or not and motherboard beep sound and power light if all this not working its mean ur motherboard is dead
Take out all of the RAM, and set it to the side. Now boot without the RAM! Does the PC beep? did you build the rig and not include the speaker? If you did not include the speaker, it won't beep and we won't know what feedback is. If you did not build the rig, you should get beeping if the Motherboard is good!