A computer system includes a triggering device; and a motherboard, connected to the triggering device, further comprising: a memory stored with a setting parameter of a basic-input-output-system; and a counter connected between the triggering device and the memory; wherein an erasing signal, for erasing the memory, is outputted to the memory from the counter according to a triggering signal outputted from the triggering device while a boosting procedure cannot be successfully executed by the computer system.