The application relates to methods and devices for determining the optimal erase and write powers for erasing and writing information on an optical record carrier. In various embodiments, the method may include facilitating detecting of a change to an element of a data processing device of the data processing environment. A gas supply conduit extends from the control valve into the blower housing, and the outlet of the gas supply conduit is disposed within the blower housing interior near the blower housing inlet and the central portion of the impeller. A plurality of generally triangular fins extend from the plates at substantially right angles to the plate bottom surfaces and extend at substantially right angles from the axes. In the second time period, the driving section writes a reset potential that makes a potential of the pixel electrode closer to a potential of the potential line.