Mechanism to prevent data loss in case of a power failure while a PC is in suspend to RAM state

A method of transitioning a computer system including a central processing unit (CPU) between power states, comprising:

• saving state information of the computer system into a first memory area;
• saving the state information into a second memory area;
• saving at least a portion of contents of the first memory area into the second memory area;
• entering a sleep state in which the CPU in the computer system is not executing instructions;
• upon a wake-up event, restoring the computer system within a first latency using the state information in the first memory area;
• and
• upon the wake-up event, restoring the computer system within a second latency using the state information from the second memory area if the state information in the first memory area is corrupted.

A computer system capable of entering a reduced power state, comprising:

• a processor;
• system memory coupled to the processor, the system memory being supplied power in the reduced power state;
• a first non-volatile memory storing state information in the reduced power state;
• and
• software operable on the processor, responsive to a wakeup event to restore state information relating to the computer system from the system memory and operable to restore state information from the first non-volatile memory responsive to an indication that the system memory has been corrupted.

Software encoded on computer readable media, the software operable on a processor in a computer system, the software operable to:

• save state information relating to the computer system into system memory prior to entering a sleep state;
• save the state information and an image of at least a portion of the contents of the system memory to non-volatile memory prior to entering the sleep state;
• cause the computer system to enter the sleep state;
• determine if contents of the. system memory have been corrupted in response to a wake-up event;
• use the state information in the system memory to restore the computer system, if the contents of the system memory have not been corrupted;
• and
• if the contents of the system memory have been corrupted, use the state information and the image of the system memory saved in the non-volatile memory to restore the computer system.