Chosen Solution
I am getting parallel, diagonal lines from top left to bottom right all the way across the screen on my 15” MabBook Pro A1150. They are made up of alternate groups of 4 small squares of red/blue and then blue on white. I can still the display behind theses lines and the cursor is no longer an arrow but a white oblong with black lines on it. I’ve tried to mirror the display on my 13” MacBook but neither will see the other. Has anybody experienced the same and can you tell me where to start looking?
What do you see when you connect your system to an external display? Your system has an older video standard DVI.
You likely will need an adapter like this one: StarTech.com DVI to VGA Cable Adapter - Male DVI to Female VGA so you can plug in your VGA monitor. If you have something else you’ll need a different adapter/
