A method and apparatus for cross validation of data using multiple subsystems are described. According to one embodiment of the invention, a computer comprises a first subsystem and a second subsystem; and a memory, the memory comprising a first memory region and a second memory region, the first memory region being associated with the first subsystem and a second memory region being associated with the second subsystem; upon start up of the computer, the first subsystem to validate the second memory region and the second subsystem to validate the first memory region.