MacBook A1990 vertical stripes on external screen

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  • ahoonid
    CapsLOCK
    • Jun 2023
    • 52
    • Germany
    #1

    MacBook A1990 vertical stripes on external screen

    Hey everyone,

    I bought a MacBook A1990 with no screen. I bought it knowing the motherboard was defective but wasn't sure what the problem was until I received it. It actually turns on but as you see from the attachment, it has vertical stripes, on an external screen!!

    The board is neat. Not opened before for sure. Just a little dust, nothing more.

    Recovery using wifi can be opened, as can also be seen in the photo but it doesn't go all the way through after connecting it to a wifi. It downloads the initial Recovery files but never completes the rest of the operation to open the macos recovery environment. After a while, it becomes unresponsive and turns the screen off.

    Fried GPU in your opinion or is this a known issue that can be fixed?
    Attached Files
    Tags: None
    • ugamazing
      Senior Member
      • Jun 2013
      • 164
      • usa
      #2
      Any change in behavior with safe boot? I imagine now, but just in case. Most likely GPU or VRAM yes. Run MEMTEST also just in case.

        Comment

        • ahoonid
          CapsLOCK
          • Jun 2023
          • 52
          • Germany
          #3
          Thanks for the suggestion ugamazing. Since no OS is installed, I can't use safe boot. I ran apple diagnostics and got VFD001 error which most probably is because no internal screen is present.

          One other weird behavior I've noticed is when I plug any bootable usb drives, the drive doesn't appear in the boot options! Sometimes connecting and disconnecting the usb shows and hides the Internet Recovery option in the boot menu! The real bootable disk doesn't appear!

          I have performed a DFU revive just in case with no change.

            Comment

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