Member Since: Jul 17, 2009
Mac Specs: 27" i7 iMac, 24" iMac, 13" Macbook Air, iPhone 5 & 5S, iPod Nano 7th Gen, iPad 2 16GB WiFi, iPad 3
06-25-2013, 12:12 PM
Welcome to Mac-Forums..
Are you sure it's OS X 10.6? If it's 2011 model, I would expect it to have Lion unless it's an earlier model..
Either way, if the system works in Safe Mode, that means that you have some application that is causing you grief. In Safe Mode, the number and types of applications that can run are restricted to almost only the native OS X ones to isolate problems..
Because things are OK in Safe Mode, you likely don't have a graphic card problem and re-installing OS X is definitely not an answer that the Apple "Genius" should have suggested..that' similar to telling someone to constantly reboot to fix a problem..
What sort of applications do you normally run? What applications start up automatically and run in the menu bar? How long after you start up does the black screen appear? Does it happen while you're using it or when it's idle?
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