Hi there Guys, Apologies if this has been posted/answered before, but Googling around I only found threads about how to change hibernation modes, or problems with MBP's not hibernating at all....mine is the opposite! I have a 13" retina MBP, a few weeks old (i7 3.0GHz, 8GB, 512GB SSD), now running v10.8.4 but it did the same on v10.8.3 as well. Using the Mac whilst connected to the mains power cord, all fine....if I then remove the power cord it'll be fine for 20-25secs, then black screens whilst it's hibernating (ie destaging to SSD)....really annoying when you're in the middle of doing something. Likewise, if the Mac has already switched the screen off, I remove the power without waking it, then wake it when on battery, it does exactly the same 20-25secs later, and re-enters hibernation! I've tried resetting the SMC, made no difference. I'm in Hibernation Mode 3...I also have a 2009 15" MBP Core Duo system (also on 10.8.4), which doesn't behave this way, so don't think it's supposed to be working this way? Any help gratefully received! If you need me to look in a log file somewhere, please just shout. Thanks Spencer.