MP All Models Mac Pro and monitor optons ...

[beamer732]

Does anyone know ... If I were to buy a new Mac Pro, could I connect my old (working) 27" 5K iMac to use it as a monitor? If so, how would that work? What cable connections would work? (My 2015 iMac only has Thunderbolt 2 ports) I assume I would have to power up the iMac, even to just use it as a monitor, right? So, that wouldn't be very energy efficient, but with the cost of new 5K monitors ... wow!
Please advise if this is feasible! Thanks!

 

[joevt]

Only old, non-Retina iMacs can be used for Target Display Mode feature.

Use your iMac as a display with Target Display Mode - The Apple Repair Station

How to use your iMac as a display with Target Display Mode by Apple Repair Station Specialist in London, UK

applerepairstation.co.uk

I'm not sure if Big Sur still supports Target Display Mode for Thunderbolt iMacs.

As an alternative, you can use some hardware/software combo:

Shop Astropad | Pro tech for reading, writing & drawing

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I believe it will use the DisplayPort signal generated by the Mac Pro GPU and transmit it to the iMac where software can display the image on the iMac screen.
Since the source is DisplayPort, it will not affect performance of the source computer, and there will be full GPU acceleration as if you were connecting a real display.
Since the output is USB or WiFi, there will be some latency (16 ms) and maybe some compression artifacts (I have not tried this product).
The output does not support 5K resolution.

Duet Display is a software only method which is not as capable. I don't think it works with a Mac as the display.

Luna Display Versus Duet Display - Astropad

When considering on-the-go workspace solutions, Luna Display and Duet Display are two options to use your iPad as a second display. Software-simulated displays like Duet Displays are limited and offer an unreliable display experience. This guide outlines the benefits of a hardware solution so...

shop.astropad.com

 

[evbtfre56]

I have not tried this, but here’s a possibly viable option: output a 4k picture via HDMI from mac pro gpu, input to imac using a 4k hdmi caputre card via quicktime, new movie recording, to input from caputre card. search amazon for “hdmi 4k capture usb 3.0” for current products. Luna uses compression, so even though its good there will be lost frames. It is a good product for basic applications.

 

[rorydaredking]

Could use this https://www.aliexpress.com/i/32965911057.html but it’s at the expense of your working iMac