Abstract: The present invention relates to a data processing system and method in which an indicator is used to provide an indication of whether or not it is safe to maintain the data processing system. Often, the first action taken by maintenance personnel, when maintaining a data processing system, is to remove the power to that system. This renders ineffective any means for providing an indication of the state of the data processing system that is dependent upon power such as, for example, the conventional motherboard power LED. Suitably, the present invention provides an indication of whether or not it is safe to maintain the system, even in the absence of power being connected to the system, using, in preferred embodiments, a bi-stable LCD, which retains its state in the absence of power.