1. A method for implementing a fault tolerant sleep mode of operation comprising the steps of: storing system state information and a value used to verify integrity of said system state information in a volatile memory; storing a copy of said system state information and said value used to verify integrity of said system state information in a non-volatile storage unit; entering said sleep mode of operation; receiving an indication to enter a normal mode of operation; and determining if integrity of said system state information stored in said volatile memory is maintained, wherein if said integrity of at least a portion of said system state information in said volatile memory is not maintained then the method further comprises the step of: reloading at least said portion of said system state information stored in said non-volatile storage unit into said volatile memory.