Failure analysis of automatic power-on on a power supply

"Fault phenomenon" a computer recently connected to the power on its own boot, sometimes inexplicably on the boot.

"Failure analysis and processing" causes this kind of failure may have the following: (1) First check whether the computer in the BIOS setup will be timed to boot function set to "Enabled", so that the computer in the set time automatically boot. (2) Again check whether the computer in the BIOS setup item to open the function of the caller's automatic power-on, when a plug in AC power, the computer will automatically start. (3) If you confirm that the BIOS has been turned off and the automatic power-on function, the computer will turn on its own, you can conclude that this is caused by hardware failure. caused by the failure of the hardware of their own boot may have the following: = +5VSB voltage Low, so that the motherboard is always a low level, so that not only will turn on its own, it may not be shut down. = The power supply itself is poor anti-interference ability, AC power connected to the instant interference caused the main circuit to start work. Then I had to change a power supply. = Motherboard ps-on signal quality is poor, in the power of an instant, the signal from low to high level of delay is too long, the main power supply is ready, and the ps-on signal is still very low, so that ATX power supply main circuit misleading, resulting in the power-on.