Dual displays

do you mean as output to the 2010 iMac that can be used in target mode?

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Well, according to this recent Apple kb article, they make it sound pretty simple IF the proper requirements are met:

Use your iMac as a display with Target Display Mode
https://support.apple.com/en-ca/HT204592


EDIT:
I forgot to add that Apple has added a note in their stupid light grey font there:
"iMac (Retina 5K, 27-inch, Late 2014) and later iMac models can't be used as Target Display Mode displays."

But I believe that has already been mentioned previously here above.





- Patrick
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when you say the 27" 5k iMac cannot be used in target mode, do you mean as output to the 2010 iMac that can be used in target mode?

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Yes, that's correct, your 27" 5K iMac can not be used for Target Mode to any other Mac. As far as what Apple stated about the HP, I don't know if that's true because we have no idea which HP you tried to connect to.

Yes, that's correct, your 27" 5K iMac can not be used for Target Mode to any other Mac.

Click to expand...

It seems that there are a few other miffed off 5K iMac users with the same problem or dilemma:
https://discussions.apple.com/thread/7976201?start=0&tstart=0





- Patrick
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