MacBook Pro 8,2 (Early 2011, 15'' Unibody 2.3 GHz i7) - OS crashes randomly, after log in screen goes all white
Many condolences. The 15" MBPs from 2011/2012 had a very high frequency of hardware failures on the logic board, specifically the onboard graphics. From recollection, it was a manufacturing fault that was not suspected by Apple's hardware designers until large numbers of them started to fail in the wild, leading to a class-action suit against Apple, which was kept very quiet. AFAIK, there is no economically sound way of fixing this issue.