4 
7 MacBook Pro's screen turns grainy, flickers and turns black
I recently received this macbook from a relative which seemed to work without a problem but recently, when turning on the laptop the screen would look grainy then after a while it would flicker and finally some parts of the screen would just be black. I tried the Apple Diagnostics (pressing D at the start) but it didn’t mention any issue. I also tried formatting my HDD from Internet Recovery and still nothing, also to mention that during the diagnostics and recovery the screen issue didn’t happen. I finally tried booting up in safe mode and it seemed to work but when i booted it normally the problem persisted.
Here is a video of the problem: https://youtu.be/bBTXtjmlfbs
I really don’t understand what the problem is, I would really appreciate some help. Thanks!
Is this a good question?
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4 Comments
Does an external display look OK connected to the Thunderbolt port (mDP or TB display or via a HDMI/VGA adapter)
by Dan
what Dan said.if external display work, then it's the panel. if so, open the case try reseating the lcd, check the pin for corrosion or bent pins.
if the external display doesn't work then it's the motherboard or gpu issue.
by Milk Mon
I just tried it with an external display, it shows the same issues as the laptop's screen.
In this case does it mean that it's a motherboard issue? Is there a way to fix it?
by Marcelo Marquez
I maybe the RAM
by Ben Capehart