I was doing my usual tasks in my early 2011 mbp. Suddenly, everything froze. I had to push the power button. From that moment, my mbp never came back. I never had a normal boot and I never managed to get into osx again. It stucks to the grey screen, after the apple logo. I tried almost every keyboard shortcut I found in apple discussions forum, here, and elsewhere, for an alternative boot. I tried to boot from a cloned disk. It stuck. I tried boot in recovery partition/mode. Blue screen. I tried to boot in bootable partitions in my usb flash disk, visible in boot, like 'drive genius', 'osx mavericks setup' etc, all stuck. I reset smc, but nothing changed. I even made an 'internet recovery', it seemed to download something for 5 minutes, but the boot stuck again. The only thing I am able to do is to press 'S' and go in this command line mode. I tried to do some repair there. I saw a 'good' message there, that the Macintosh HD volume is ok. But when I booted, I stuck to grey screen again. I am not completely sure, but I think I saw for a few seconds (before they vanish in the upper direction of the screen) an 'smc error' in the blue screen of this blue screened text environment. Can you please guide me to find out what the problem is? I am really disappointed.