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I have a MacBook Pro 2011 with the well known AMD GPU failure. So I know about the procedure to de-activate the AMD GPU and activate the Intel GPU on the mainboard. This has to be done via the command line in Terminal, for which you need to start Recovery Mode and get into OSX Utilities and then start Terminal.
Unfortunately, booting in Recovery mode ends before I get into OSX Utilities. The screen goes grey and then either shuts the system down, or it starts rebooting.
The MacBook is currently installed with High Sierra.
What can I best do?