Abstract: A complex signal processing system for multiple fans is used to control the rotation of a first fan and a second fan. The speed signals of the first fan and the second fan are processed through an XOR operation to obtain a complex speed signal. In response to the complex speed signal, the speed and the operational status of the first fan and the second fan can be evaluated.

Abstract: A system and method is provided for monitoring the speed signals of a first fan and a second fan. The system includes a selection signal generation device, a logic gate, a counter and a control device. The selection signal generation device outputs a selection signal to the logic gate having two different states. Based upon the speed signals and the state of the selection signal, the logic gate outputs an output speed signal representing the speed signal of the first fan or second fan to the counter. The counter converts the output speed signal to a digital speed datum. The control device calculates the speed of the first fan or the second fan according to the selection signal and the digital speed datum. The changes of state of the selection signal permit the system to obtain the respective speeds of the two fans in different access cycles.

Abstract: A complex signal processing system for multiple fans is used to control the rotation of a first fan and a second fan. The speed signals of the first fan and the second fan are processed through an XOR operation to obtain a complex speed signal. In response to the complex speed signal, the speed and the operational status of the first fan and the second fan can be evaluated.

Abstract: A multiprocessor system according to this invention comprises a main board, an expansion board, and at least a connection card. The main board comprises a plurality of first processors, such as four (4) CPUs, and at least a first socket. The expansion board comprises a plurality of second processors, such as four (4) CPUs, and at least a second socket. The plurality of first processors selectively communicates with each other by way of a plurality of first processor buses, which may be dual unidirectional point-to-point buses such as HT buses. The plurality of second processors selectively communicates with each other by way of a plurality of second processor buses, which may be dual unidirectional point-to-point buses such as HT bus. The connection card(s) electronically connect(s) to the first socket(s) and the second socket(s) for providing connection between at least one of the first processor of the main board and at least one of the second processor of the expansion board.

Abstract: A multiprocessor system is disclosed, which comprises a plurality of processor unit, such as eight processor units, and a plurality of interconnection bus that may be a dual unidirectional point-to-point bus. Every interconnection bus connects predetermined two of the processor units. Particularly, at least two of the interconnection buses are crossed to each other.