I currently have a 50m Thurderbolt 3 USB-C Corning cable connecting my Mac Pro (in a closet) to an XDR display on my desk. I recently bought a second XDR display to use together with the one I already have. Do I need to connect the second display directly into the Mac Pro or is there a way to daisy chain the second one to the one I already have connected to the Mac Pro? Would like to avoid buying and connecting a second 50m corning cable if possible, as these cables are expensive and I'd have to run the second one through the wall like I did with the first one (pain in the ass). Thanks for any information or suggestions.
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Daisy chaining 2 Pro Display XDRs to 2019 Mac Pro w/ W5700X
- Thread starter Fhed3040
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I think someone was able to use a thunderbolt 4 dock to do 2 studio displays at 5k60hz. Not sure it’s possible with 2 XDR’s at 6k60hz
It should work.
Either a Thunderbolt 4 hub or dock will allow connecting two HBR2 x4 displays.
Both the Studio Display (pixel clock: 936 MHz) and Pro Display XDR (pixel clock: 1286 MHz) use HBR2 x4 with DSC@12bpp (max pixel clock 1440 MHz).
A Thunderbolt 4 hub such as the CalDigit Element Hub will be less expensive than a Thunderbolt 4 dock.
macOS only shows the framebuffer resolution and framebuffer pixel depth.
You need a different method to show the output resolution and output pixel depth.
You can use SwitchResX, double click the current resolution in the Current Resolutions tab, and see the pixel clock and active pixels in the timing info.
You can use the AGDCDiagnose command to show the output resolution, the output pixel and color info (including DSC and chroma subsampling info), and connection link rate and lanes and other DisplayPort info.
/System/Library/Extensions/AppleGraphicsControl.kext/Contents/MacOS/AGDCDiagnose -a > "$thefilename" 2>&1My AllRez command should be able to show the info as well, plus some DDC/CI / MCCS info:
https://github.com/joevt/AllRez
Yes, if that was the currently selected resolution.
Pixel clock is 1286 MHz and active pixels is 6016x3384 which are expected for this display.
Scale pixels is 3384x6016 which probably means you are rotating the frame buffer 90° or 270°.
If you were scaling 6K to 4K output (which would happen if you connected the display to a DisplayPort output that is not Thunderbolt and does not support DSC or if you added a custom 4K timing and set 4K as the Scaled resolutions base), you would see pixel clock 533 MHz and 3384x2160 active pixels and "Scale to" set to 6016x3384.
SwitchResX might have a 4K timing already defined from the XDR EDID. See if there is a 3384x2160 mode that is not scaled (or use "Show best resolutions for display in bold"). The "Scaled resolutions base" setting is in the Display Information tab.
Pixel clock is 1286 MHz and active pixels is 6016x3384 which are expected for this display.
Scale pixels is 3384x6016 which probably means you are rotating the frame buffer 90° or 270°.
If you were scaling 6K to 4K output (which would happen if you connected the display to a DisplayPort output that is not Thunderbolt and does not support DSC or if you added a custom 4K timing and set 4K as the Scaled resolutions base), you would see pixel clock 533 MHz and 3384x2160 active pixels and "Scale to" set to 6016x3384.
SwitchResX might have a 4K timing already defined from the XDR EDID. See if there is a 3384x2160 mode that is not scaled (or use "Show best resolutions for display in bold"). The "Scaled resolutions base" setting is in the Display Information tab.
Only if you use a DisplayLink adapter for the third display or if you boot Windows or Linux and connect an MST hub or if you use a video wall processor or similar device to combine displays into one display.
Can you please elaborate more on the DisplayLink adapter method? Any recommendations for a good one?
DisplayLink uses USB instead of DisplayPort. The video is greatly compressed (≈1 Gbps) compared to DisplayPort (≈16 Gbps for 4K60). Search for related YouTube videos to see if the result is good enough for your work.
Try any of the 4K single DisplayPort port options which will be less expensive then options having more ports.
https://www.synaptics.com/products/displaylink-graphics/displaylink-products-list