I've performed dozens of searches to find an answer with no luck... Mac Pro: 2 x 2.66 UPS: CYBER POWER CP1500LCD, USB plugged directly into MP, using OS X Energy Saver prefpane (no 3rd party programs) Everything is fine when the MP is awake and running normally. But if I sleep it, then kill power to the circuit the UPS is on, it won't wake up. If I unplug and replug the USB cable, it causes the MP to wake and the warning about power failure pops up. Any ideas? It's not a crisis as the MP will sleep on battery for quite a while... but I'd still prefer it to wake and shutdown gracefully.