I recently upgraded my MacBook Pro to Yosemite. Everything was fine … then suddenly the MacBook Pro does not start up. It boots with some distorted graphics, and then just immediately restarts.
I tried Recovery by pressing shift key. Command + Shift. Nothing. Same thing…Apple logo..progress bar, grey screen, fan speeds up … shutdown.
I tried Apple's recommendations. But surprisingly same sequence..
- Option-Command-P-R — It did give me sound twice and above sequence
repeats. (I don't see those icon etc for hardware test..why ?) - Pressed shift, same sequence repeats.
- Command V Video here … no error but same sequence … it shows grey
screen and restarts.
Best Answer
What is the year and model of your MacBook Pro? There is a known graphics failure in the 2011 models of MacBook Pros that is now leading to a class-action lawsuit .
I would also try resetting just the SMC by pressing Shift+Control+Option+Power button at the same time while the computer is off and plugged into power. (You only reset the PRAM according to the steps you have done above.)