Block Lines on the Display & Freezing
I get these lines and unit freezes shortly after booting into recovery or into any OS.
This to me is somewhat what happens if you adjust the screen resolution & restart, these lines appear as the graphic setting switches at boot, at least from memory when I did that in the settings to help my poor vision in the past. But, this time the system suddenly freezes and the display is flickering at the same time. I don't know what system was previously installed so I am trying to start fresh with Mountain Lion or Mavericks working my way upto Catalina, at least that is my plan. There is no indication in the boot menu that OCLP was ever installed as there is no EFI Boot option, so Is this a graphic chip failure (Dead unit) or a driver issue. I did manage to run diagnostics and it gave me the dreaded EFI driver issue in the report, but then it still boots normally which is odd as if the EFI driver was the issue it wouldn't fully boot. I have reset the PRAM and SMC to no avail. Occasionally I get the 3 beep RAM issue, but it was not mentioned in the diagnostic.
Is this a good question?