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GC-ALPINE RIDGE in hands

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I am looking for any reports of using DDC/CI to control brightness of the LG UltraFine 5K. What app did you use and did it work?
 
Joined
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@joevt I wrote a utility to do this, but DDC/CI is hilariously broken on the LG 5K UltraFine. You could try using one of the utilities out there, and it will work for setting the brightness, but it will never report the correct brightness.

Your best bet is to find a way to re-init the onboard USB hub in the screen after connect/disconnect (which is what I assume you're facing?)
 
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GIGABYTE Z170X-Gaming 7
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@joevt I wrote a utility to do this, but DDC/CI is hilariously broken on the LG 5K UltraFine. You could try using one of the utilities out there, and it will work for setting the brightness, but it will never report the correct brightness.

Your best bet is to find a way to re-init the onboard USB hub in the screen after connect/disconnect (which is what I assume you're facing?)
I don't have an LG 5K display. The problem I'm facing is that I keep saying it may be possible to control the brightness using DDC/CI but nobody tries it or they don't report failure/success so I can never be sure. Even from the you, I haven't seen an explicit statement of success/failure. You say you wrote a utility to do this, but you didn't say your utility does that.

Re-initing the onboard USB hub is not a solution for people using a GC-ALPINE RIDGE to power an LG 5K display where the add-in card is not in a motherboard that supports add-in cards.
 
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ASUS Prime X299 Deluxe
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Vega 64
Well, I'm telling you very clearly - I wrote a utility to control display properties via DDC/CI. I have an LG 5K UltraFine display.

The display reports the wrong information via DDC/CI, so while it is possible to send commands to the display, there is no guarantee of the current state of the device via DDC. The display has an internal USB device that is used by macOS to control the various properties on it's internal USB 2.1 hub "USB Controls".

Does changing brightness work via DDC/CI? Yes, it did for me. However, it wasn't reliable and while you could send through values, even the min/max values were filled with garbage data on this display.

The USB controls work fine with my X299 build under macOS, via TB3 on a GC Alpine Ridge add-in card (at least until the display is disconnected).
 
Joined
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Messages
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GIGABYTE Z170X-Gaming 7
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i7-6700K
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GTX TITAN X
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iMac, MacBook, MacBook Air, MacBook Pro, Mac mini, Mac Pro
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Apple, LC, Power Mac
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Does changing brightness work via DDC/CI? Yes, it did for me. However, it wasn't reliable and while you could send through values, even the min/max values were filled with garbage data on this display.

Thanks for that. Did DDC utilities have the same issues in Windows? Intel graphics vs AMD?
 
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Sorry, no idea - I don't use Windows.
 
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Has anyone successfully used the GC-ALPINE RIDGE rev 2.0 card to passthrough dual displays using both USB-C outputs? I'm trying to use two LG UltraFine 4K displays, but can only get one to work.
 
Joined
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Motherboard
GIGABYTE Z170X-Gaming 7
CPU
i7-6700K
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GTX TITAN X
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iMac, MacBook, MacBook Air, MacBook Pro, Mac mini, Mac Pro
Classic Mac
Apple, LC, Power Mac
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iOS
Has anyone successfully used the GC-ALPINE RIDGE rev 2.0 card to passthrough dual displays using both USB-C outputs? I'm trying to use two LG UltraFine 4K displays, but can only get one to work.
Did you try each DisplayPort input separately to verify that they both work? Same with the DisplayPort outputs of the graphics cards.
 
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Did you try each DisplayPort input separately to verify that they both work? Same with the DisplayPort outputs of the graphics cards.
Yes.

My GPU has two DisplayPort outputs. In testing, I connected one of the outputs to the GC-ALPINE RIDGE on Mini DisplayPort input 1, which passes through to the LG UltraFine 4K on USB-C output 1. Simultaneously, I connected the other GPU DP out directly to another display with a DP in, and the two displays work normally.

Another scenario I tested is connecting both GPU DP outputs to the Mini DP inputs on the GC-AR, along with one LG UltraFine 4K connected to the GC-AR, and another display connected via HDMI to the GC-AR. Both displays work in this case, however, the GC-AR input/output routing is strange: the Mini DP input 1 gets routed to the HDMI output, and the Mini DP input 2 gets routed to USB-C output 1, not output 2.
 
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