Macintosh computers that use an Intel microprocessor do not use Open Firmware. Although many parts of the IO registry are present and work as expected, information that is provided by Open Firmware on a PowerPC Macintosh (such as a complete device tree) is not available in the IO registry on a Macintosh that uses an Intel microprocessor.
Software has bugs?? OMFG! This world is rolling straight to heck.
I would not recommend putting your peripheral in a dishwasher. Not as dangerous as sticking it into a vacuum cleaner hose, but no fun nevertheless.