Can't wake MBP, must power off/on each time. Help please?
I Can't wake my Mac Book Pro 17' 2009 out of sleep mode after installing Mountain Lion. Have to power off then power back on each time. Machine runs like crazy but only for a dark screen. It won't turn off easily using on/off button, either. Once the screensaver has run it's time the screen goes dark. I've tried the usual modes of putting it to sleep, even logging off, but nothing works. It surely doesn't sound like it's sleeping either, more like it's going to die from exhaustion. Can anyone help, please?
MacBook Pro, OS X Mountain Lion (10.8.2), 17in. 2.66 GHz