Patent ID: 7639063

Claim:
A circuit for automatically turning on and off a motherboard repeatedly in a motherboard test, the circuit comprising: a first switch module comprising a first terminal arranged to receive a standby power and connected to a sixth terminal of a computer front panel header which controls turning on and off of the motherboard, a second terminal arranged to receive the standby power, and a control terminal; a timing circuit charged by a system power; and a second switch module comprising a first terminal connected to the control terminal of the first switch module via the timing circuit, a second terminal arranged to receive the standby power, and a control terminal arranged to receive the system power, wherein, when a power of a computer system is turned on to start the motherboard test, the sixth terminal of the computer front panel header is at a high level, the first switch module is turned on to make the sixth terminal of the computer front panel header at a low level for turning on the motherboard, the second switch module is turned off, and the timing circuit is charged by the system power; when the system power is lost, the second switch module is turned on and discharges the timing circuit for turning on the first switch module after a discharge time, and the motherboard is turned on when the first switch module is turned on to ground the sixth terminal of the computer front panel header.