Hey guys, today my Macbook early 2011 (Yosemite) just suddenly shut down by itself. I tried restarting it and I get to the loading bar but it loads to approx 30% and then it seems to just jam up. I've tried everything. Resetting PRAM, recovery mode, diagnosis mode, safe mode, reset SMC and it's the same thing, loading bar goes to 30% and then it jams up. Except when I restarted by holding option D and manage to do a hardware test which showed no problems. Any ideas what's going on?