4 
2 Black screen during boot
Hello all, I have an iMac that, under normal conditions doesn't fully boot, pressing the power button I get the chime with the Apple logo, a progress bar starts but before I get to the login screen the display goes black. The only way to get it back is to unplug the iMac and plug it back in, but in the end the exact same thing happens.
The big catch here is that it boots and seems to work perfectly fine in Safe mode.
This is fresh install of macOS, so my question, would anyone know if a bad or failing hard drive would cause this sort of issue??
TYIA
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1件のコメント
I have exactly this problem too. What did you do about it in the end?
In my case, this has been going on for years, but now I can barely get the machine going once in every 30 attempts. I got an error report & fed it to ChatGPT, which said:
"This suggests that the graphics driver for the AMD Radeon card (part of the AMDRadeonAccelerator and IOGraphicsFamily kexts) is malfunctioning when attempting to change display modes. The crash seems to occur during the WindowServer process, which manages the graphical user interface (GUI), indicating that the system is failing to properly initialize or communicate with the GPU."
Max Bleyleben さんによる