I was using as usual my mbp 15 late 2013, when suddenly the screen started to bounce! Up and down all the time, like someone shakes the screen! I powered down the mbp, but when I power it again, the same thing happened again. I am so dissapointed by Apple. My last computer was mbp early 2011. It died some months ago. Logic board problem, no applecare, no sense to repair it and possibly have the same problems after a while. So, I purchased this one, the high spec model, 16gb ram, 512gb ssd, 2nd graphics card etc. And now what? With this machine I got an 'apple care' package too, so in any case they will repair to free for me. But why should I have such a discomfort again? Take it to the service, calls, lots of days without my main computer/mbp, etc. Why all these? And why again in a few months time? 2 different Macbook pros, with problems, at the same year? Isn't it too much? Next time maybe should I take a better look to pc laptops. I thought that apple makes the best laptops in the world. If they want to focus in iphone, there is no reason to having such problems. I cannot stop thinking all these. But lets get back to the problem. I tried to reset smc but nothing changed. Press shift-alt-command+power button. The mbp boots, but from the first moment, the screen bounces. I can press the keys in login screen to get in osx, but as you maybe guessed, everything bounces. Is there anything that I could do? Is this a hardware problem? Any other user with similar problem? I hope there is something to fix it by myself, because this year was a real 'apple' disaster for me.