Do these horizontal lines on MacBook screen signify logic board or graphics card failure? My friend has been experiencing problems with his MacBook recently. The machine powers on but at some stage, usually during the boot, it will freeze and the display will look as pictured with black and white horizontal blocks on screen, arranged in 5 columns. Very occasionally it will boot all the way to open the user profile and allow a few minutes of normal use before the lines appear.

Apple Hardware Test doesn't highlight a problem. On the couple of occasions that macOS Recovery did load, Disk Utility ran First Aid without any errors.

We would like to know is the odds of a hardware problem e.g. graphics chipset or logic board?
MacBook support USB target disk mode so you should still be able to boot and back up the data from the storage and/or pay for just labor when it goes in for hardware repair.

It might be hard to see what’s up, but most times this is GPU / cabling when you have those glitches - it’s less likely just the screen based on the image.

You might even be able to connect the Time Machine drive or navigate carefully and set up Time Machine and let it run overnight to get a backup still. That will also let you know the GPU / graphics is the only failure and not the core processing and storage.



Since the MacBook has a unified storage / logic board / GPU - it won’t matter so much what fault is as 95% of the repairs will be to swap out that assembly entirely and send that part back to get refurbished in the factory. A mail in repair for this would be covered under AppleCare or warranty in all likelyhood and if you paid for an official repair, expect less than $350 for parts and labor and shipping and testing in the US.