iMac mid 2011 27“ does not fully boot after logic board replacement

Thank you! Yes I used high sierra and there is no way to know which OS was used before. I never would have had that thought 😆 I’m pretty sure I have one somewhere because I once restored my iMac to factory setting and was stuck on lion with no way to log into the appstore to update again

@qa1ysllewbt5zkq - How did you create the drive? You do need to build it from a Mac

I used the original drive from before the mac broke (macos and windows 10) and a copy of a slightly older state with only macOS high sierra on it that I meant to replace it with but never did. I am currently trying to install a different version on it from my macbook that has sierra installed. But installing sierra on the drive on a sata to usb adapter somehow does not work it gets an error at the end, no idea why it just says install again

The only thing that runs on the imac is ubuntu from a usb in safe graphics mode. Not sure if that means that the gpu is broken or not.

The usb installer ones I created on my macbook that has sierra on it. Dl the dmg then used the terminal command on the apple website sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/MacOSEL/ --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app

@qa1ysllewbt5zkq - Still a bit confused on what you are doing with all of these OS's. You point out Ubuntu works in Safe Mode, so that aims us to a failed AMD Radeon GPU as Safe mode is using the Intel graphics engine.

How about creating a fresh OS installer boot drive first grading the newer release of High Sierra from here How to download and install macOS as the certificate was refreshed within it. Then follow this guide Create a bootable installer for macOS as I'm not sure the method you used is correct.

That is the exact guide I followed the commands for the terminal are further down. The mac would not boot El Capitan or high sierra installer usb 😅 installing el capitan from my macbook to the ssd worked but isse persists. So yeah if the ubuntu does not use the graphics card at all, that would explain it. I used cmd + v as well to see the boot process but I don’t really understand what most of it means😅

I can’t really find a fitting gpu right now that is not ebay and a bit fishy.

I‘ll try to add the pictures I got from the cmd+v startup to my initial question.