A computer system including a processor and a memory is provided. The processor includes a microcode executing unit and a programmable fuse which stores trusted information which is pre-generated using China commercial cryptography algorithms. The memory is operatively coupled to the processor and is configured to store a trusted module and a digital certificate of the trusted module. The microcode executing unit uses the China commercial cryptography algorithms to authenticate the digital certificate according to the trusted information, and authenticates the trusted module according to the authenticated digital certificate.