Chosen Solution
Hello, I have a mid-2007 iMac that I upgraded to a core 2 duo T9500, aswell as switching the original hard drive for a 2.5 in 1 tb hard drive. I original received it running El Capitan, which I then upgraded to catalina, after some time I moved to Linux mint, and I have now after much work reinstalled MacOs and I am currently running MacOs High Sierra. The issue I am having is that none of the keyboards or mice that I plug into any of the ports are being detected, and it is effectively dead in the water, as I can’t log in. The only time I can get them to work is if I am in the boot picker, any other time they simply aren’t detected. Has anyone else had this issue, or heard about it?
Are you able to create an external bootable FireWire drive from anther Mac system with Lion OS-X 10.7.5 which is the highest level of OS-X you can run on this system. From what is sounds like you pushed the system beyond what it was designed to run. Pushing it to Catalina I think did you in. You’ll need to return your systems EFI if you can’t get the external boot drive to boot up.
