Will not power on - but not so simple...
I have just changed out the logic board after the typical graphic card failure on my early 2011 17" MacBook Pro (found what looks like a used board from a company in France, based on the discolouring around the screw holes).
On the first try, the computer started, but the display screen was weird with lines and strange colours, so I opened it up again to clean the display cable connector with isopropyl alcohol.
After this, the computer booted, with totally normal screen colours. But at the log in screen, my password (which I have used for many years) was not accepted. After a few attempts I was asked for the master password, which I entered and which was not accepted either.
I then shut down the machine to go and search for a solution to the login problem.
When I came back, the computer would not start. Magsafe light totally normal green with the battery disconnected, turning amber when the battery is connected.
Tried SMC reset, but nothing, completely dead. Is there anything else to try or is it possible that the new logic board is defective?
Is this a good question?