What it is for if you press and hold down the power button on a Mac Pro? The light flash really fast and make a really loud beep. I know this is use for Firmware upgrade, but I try to restore a Firmware update but couldn't. I try holding the power button while the computer start up see what it for but I get a blank screen afterward. Is this going to screw up my Computer? I force shutdown already and already went back to Mac OS X just fine.
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Pressing and holding the power button
- Thread starter Neonguy
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If you are back in Mac OS X already and it's working fine, I wouldn't worry about it. You should only have to shut your Mac off that way after a hard lock or kernel panic. If you are trying to apply a firmware upgrade, try and follow the software instructions again. If it went positively before, it would most likely tell you.