Tony, you mentioned that Apple recommends leaving it on as it does the first aid around 3 am. What if I'm going to bed, and I put it to deep sleep? Does it come on anyway to go into first aid mode? Should I go into the System prefs and uncheck the "put the hard disk to sleep whenever possible" in the Energy Saver control panel? I too use Onyx every so often (probably less than I should), but most of the time I just use that instead of shutting down the Mac, which saves on electricity. Eric