A boot-up operation system is provided. In one exemplary embodiment, the system includes a CPU, a bootstrap memory, a boot memory, a main memory, an I/O port and CPU operating system code. When the system is turned on, the CPU executes the bootstrap program which directs it to determine whether the boot memory contains the necessary code to perform the boot-up operation. If the boot memory contents are usable for boot-up operation, the CPU starts executing a boot program that is stored in the boot memory. If the boot memory contents are not usable for boot-up operation, the bootstrap program directs the CPU to download a copy of the CPU operating system code from outside the system using the I/O port. After the download, the CPU stores a copy of the downloaded operating system code and the boot program into the boot memory for future use.