A computer has a platform controller hub (PCH), a field replaceable unit (FRU), a memory, a complex programmable logic device (CPLD) and a basic input output system (BIOS) chip. The PCH has a first port and a second port. The FRU and the memory are both electrically connected to the first port of the PCH. The CPLD is electrically connected to the second port of the PCH, and used for detecting an indicating signal from the second port to selectively generate a reset signal. The BIOS chip is electrically connected to the PCH, the FRU, and the CPLD, and used for making the computer rebooted in a manufacturer mode or a normal mode according to the reset signal.