plist files (where the hidden settings could have been stored) - could use some software like CleanMyMac for an easier location of them - and only then make a clean install of your softwares Are you sure that you've removed the AMD drivers? The description of their removal is available at my original instruction

I could recommend removing them completely together with their. Are these modded EFI bin files available somewhere? (sorry if I've skipped this moment) During the installation these softwares probably saw your discrete GPU as available and set up themselves accordingly. In the worst case you'd have to reinstall your OS before moving forward with EFI variable fix Check your filesystem with fsck to make sure everything is OK there, please let me know if it doesn't help Thank you very much for this message, you wrote a great manual at your website. If you can't reach even the save mode, connect your OS X hard drive to another Mac or PC with Linux (see my original instruction for the description how to do it). In any case its worth trying this fix just to see if it helps, if we don't have any better ideas at the moment Start with checking your filesystem (if necessary) and then removing the AMD drivers.

Yes, its likely that your GPU has failed. after OS X update or full battery discharge) So I recommend you to repeat a fix again and see if that helps You need to enter this whole long command completely, in one-line command, and then press the 'Enter' key to execute:

Also you're welcome to try the alternative instructions which could be also found at this thread If you've started observing the glitches again, that means something went wrong with your fix (e.g. Its OK if you don't have a gpu-active file, just make a new one with the correct contents as specified at the instruction Are you sure you're entering the command correctly? Some people had a problem with a different quotation symbol '.

Virtualbox extension pack 5.2.12