That could be a numerous amount of things..
Make sure the voltage switch is set to the correct amount of voltage on the power supply. (If it's on one side switch to the other and try to power the computer on)
Make sure the power button wire is correctly connected to the motherboard.
Make sure there is nothing loose(like a screw) between the motherboard and the case.. This has happened to me and it sucked.
Last thing to try is flip the switch on the power supply to off and hit the power button a few times, flip the switch back on and see if it'll power up.
Make sure the voltage switch is set to the correct amount of voltage on the power supply. (If it's on one side switch to the other and try to power the computer on)
Make sure the power button wire is correctly connected to the motherboard.
Make sure there is nothing loose(like a screw) between the motherboard and the case.. This has happened to me and it sucked.
Last thing to try is flip the switch on the power supply to off and hit the power button a few times, flip the switch back on and see if it'll power up.
