an apparatus for processing items of electronic equipment , such as downloading software to and / or testing pc system units , includes a rack having a plurality of cells each for accommodating a respective unit to be processed . each location has a visible indication , e . g . a colored light , of the instantaneous processing state of the location , such as : cell empty , processing in progress , processing successfully completed , processing failed and unable to commence processing . each cell also includes a timer to measure the period of time for which the cell has been in the state indicated by the visible indication .