Randomly on my laptop screen this appears and debian just freezes. Sometimes these vertical lines don’t appear and system freezes anyway. Its just random. How do i identify if this is hardware or software issue? and then how to identify exact piece of hardware or software causing this problem.
nope this is macbook pro 2012
Ok. Please add these infos, also the ones you added in comments, to your main post.
Otherwise you need to understand that not many people can help you