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Q: MacPro refuses to wakeup. Clicking either the mouse, trackpad, keyboard, or front power button, fails to work . I have to remove and reconnect the power cable to Reboot. Sometimes I need to repeat this steep because the power button fails to do the job. This Mac is a Mid 2010 2.8GHz Quad-Core Intel Xeon refurb from Apple, running macOS Sierra 10.12.6 w/ 8 GB DDR3 Memory, ATI Radeon HD 5770 1024 MB. I have Energy Saver set to sleep @ 20 min, and Display @10min. With the options : “Put hard disk to sleep when possible”, and “Wake for network access”. An Apple TrackPad is connected w/Bluetooth, and an Apple Extended Kb connected via USB.
When this happens is your front power button light on, is it dim, is it slowly flashing? Have you upgraded your operating system lately, if so, was it doing this before the upgrade? Are you experiencing any random shutdowns?