AlxGa1-xN materials and device technology for solar blind ultraviolet photodetector applications

A power fault diagnostic mechanism for a computer system having a power system that includes a controller. A variable is recorded in a non-volatile memory associated with the power system. The variable assumes a first state when the computer system is powered on and operating. The variable remains in the first state until it enters a second state when the computer system is powered off in response to a power-off request. The controller operates in a standby mode when the computer system is powered off. Upon being powered up, e.g., after a utility power disturbance, the controller reads the variable in the non-volatile memory. This allows determination of whether a disturbance has occurred, even when the computer system was powered off. The controller maintains a local error log based on the variable accessed from the non-volatile memory. A system error log is updated by the operating system using the local error log.