iMac was running fine but suddenly loses graphic acceleration.. What I did wrong?

iMac was running fine but suddenly loses graphic acceleration.. What I did wrong?

Hello guys, I would just like to report a situation that happened here to understand what I did wrong... I installed OCLP and Sonoma on my 2013 iMac (21'5) in january without issues and the machine was running tottaly fine (and fast!) until last wednesday.

I started up the iMac in the wednesday morning and all seems to be fine, but noted that all graphic acceleration was gone.. It turned sooo slow on opening Chrome and minimize apps windows, for example, and the dock lost its transparency.

I am 100% that I did nothing - OCLP was warning that a new version was avaliable, but I cancelled these alerts a few times. I did not updated the machine to 14.2 and 14.3, precisely because I was afraid to mess with the system. It was smooth, there is no reason to update.

As the machine turned almost complete unusable with no graphics, I decided to open OCLP and reinstall the root patches. I did it, but from this moment the computer didn't started anymore - I get only the Apple logo and the screen in the picture.

I managed to fix the mess reinstalling Success' href='/2020/12/install-macos-catalina-on-supported-pc.html'>Catalina from the Internet Recovery and, from there, I updated the iMac again to Sonoma 14.4 via OCLP (and again, smootly with no issues).. Fast and easy, and it is running fine now. But I had to erase/format the SSD to be allowed to do that procedure.

Sorry if my question is too dumb, but I wonder to know what the hell I did wrong and why the machine suddenly looses the grapphic acceleration, as the automatic updates are turned off, to be aware in what to do if this happen again - without looses all my files and apps doing a clean installation again.

Thank you sooo much for all support =)

https://preview.redd.it/v3vel3l8aosc1.jpg?width=2252&format=pjpg&auto=webp&s=bdfa4ffd6c1bfc2110c811409bcc50045238ba34

Author: @danielsigma