Hi all. I've been having a problem with my late 2011 MacBook pro whereby it won't boot up 90% of the time. It gets as far as the apple logo and then I get a white screen. When I have got in I've tested the ram sticks and they seem to be fine and also have tested the hard drives which both seem to be fine. I was running high Sierra when the problem occurred and I managed to use internet recovery to revert back to lion osx. Currently when I try and boot up in safe mode I'm getting a blue screen. When I do get in the computer seems fine and then will randomly freeze to the point where I need to hold the power button to restart. I've had instances where the screen becomes split. I'm aware that there was a logic board problem with this model of mac and my logic board was replaced under the extended warranty program 2 years ago. I've entered single user mode and used fsck -fy which initially tells me the file system was modified and then when I run it again it says file system appears to be ok. From the symptoms I've described does it sound like the logic board has had it again?