Here is the fix for 2011 MBPs, DON'T REPAIR the Video Card, they just die again eventually. This is the FIX and is best to use like Mountain Lion or even Snow Leopard, and just MAX.
SOLVED: MacBook Pro 2011 GPU Glitch - MacBook Pro 17" - iFixit
Takes some patients, use a backup drive to CCC. And you'll be fine. The reason to use the older OS is because you get sleep functions and no lag or jitter in the screen, i.e. the MBP will use the Intel GPU 100%.
Have fun!!
SOLVED: MacBook Pro 2011 GPU Glitch - MacBook Pro 17" - iFixit
Takes some patients, use a backup drive to CCC. And you'll be fine. The reason to use the older OS is because you get sleep functions and no lag or jitter in the screen, i.e. the MBP will use the Intel GPU 100%.
Have fun!!