1. A method of loading a trustable operating system comprising: performing a start secure operation by a first processor of a plurality of processors; performing a join secure operation by remaining processors of the plurality of processors excluding the first processor, the join secure operation performed from the start secure operation and forces the remaining processors of the plurality of processors to enter into a halted state that prevents the remaining processors from interfering with the operations of the first processor; receiving signals by the first processor from the remaining processors that the remaining processors have entered the halted state; identifying a secure region in a memory of a computer; loading a content into the identified region under control by the first processor after receiving the signals that the remaining processors have entered the halted state; registering an identity of the content after the content is loaded into the identified region, the registering comprises: recording a hash digest of the content of the identified region, and signing the hash digest with a hash signing engine having a secure channel to access the hash digest, the signed hash digest being stored in a register in the memory of the computer that is accessible by an outside entity to verify whether the content can be trusted; causing the first processor to jump to a known entry point in the identified region in the memory; and completing the start secure operation by the first processor and signaling the remaining processors to resume activity by exiting the halted state and jumping to the known entry point in the identified region in the memory.