I don't see screen for pram reset, recovery os, os installation

[Guest Mad Kat]

Hi, I am in a position to no longer be able to reset pram, nvram, macOS recovery, OS High sierra installation

 

The problem is that every execution wants to do by turning off Mac Pro 5.1 and holding down key composition or single key, I feel it starts up but the monitor remains black without showing me the screen

 

I do not understand if due to having transferred ssd with system on pcie card, or the new 4k Lg monitor that if started system normally ok, if with key combination .... nothing...

 

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Source: MacRumors