I used to do a ton of work with old Dell Optiplex machines, which have handy status lights which tell you what’s wrong when they break, which, they often do. Dell has pretty good documentation for what the various lights and beeps signify, but it can be a bit cumbersome pulling out a PDF and cross referencing lights. This tool lets you interactively diagnose problems with Optiplexes built from 2005 onward (mileage after 2015 will vary as I stopped managing that fleet around then and haven’t updated the tool).
