A secure boot processing may be accomplished on the basis of a non-volatile memory that is an integral part of the CPU and which may not be modified once a pre-boot information may be programmed into the non-volatile memory. During a reset event or a power-on event, execution may be started from the internal non-volatile memory, which may also include public decryption keys for verifying a signature of a portion of a boot routine. The verification of the respective portion of the boot routine may be accomplished by using internal random access memories, thereby avoiding external access during verification of the boot routine. Hence, a high degree of tamper resistance may be obtained, for instance, with respect to BIOS modification by exchanging BIOS chips.