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Ma3n-87

macrumors member
Aug 30, 2008
34
3
You tested both cables - and each one works with a single LG 5K?
If you connect two then only the first connected LG 5K will work?

Maybe your Thunderbolt ports don't support two displays? Do you have two normal displays that you can try to connect to the Thunderbolt ports?

Do you know if the LG 5K works at 5K resolution with a Thunderbolt cable?
If you use a normal USB-C cable, does it work at only 4K? Did you try creating a 5K39 timing using CRU?
yeah that's correct both cables worked with each of the monitors individually. The max resolution I get with them is a little higher than 4k (4096x2304).

I do get the 5k (5120x2880) resolution while using the thunderbolt cable supplied with the monitor but it seems that's only if I'm using a single 5k monitor (or using a single monitor thru TB and the HDMI connection to connect the other monitor (the lenovo one).

The thunderbolt ports are supporting two monitors, right now I have the LG5k and a lenovo 4k connected to the TB3 ports (the lenovo works with a USB-C to DP cable which flickers with certain apps, and the USB-C to USB-C cable which works fine). It's just the 2 5K LGs that are not working concurrently. I haven't tried creating that custom timing (but I really can't if the second monitor won't even show up).
 

Ma3n-87

macrumors member
Aug 30, 2008
34
3
Maybe your Thunderbolt ports don't support two displays? Do you have two normal displays that you can try to connect to the Thunderbolt ports?
The other caveat is that I have to connect the non-LG monitor first (USB-C to USB-C or USB-C to DP), then connect the LG5k monitor
 

joevt

macrumors 604
Jun 21, 2012
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The other caveat is that I have to connect the non-LG monitor first (USB-C to USB-C or USB-C to DP), then connect the LG5k monitor
Ok, so how about this:
1) connect non-LG to port 1 (this takes away one HBR2 DisplayPort connection)
2) LG to port 2 (this uses the remaining HBR2 connection and limits the display to 4K because there's not another HBR2 connection for dual tile 5K60)
3) disconnect non-LG from port 1 (this releases the first HBR2 connection - hopefully the LG won't take it)
4) connect second LG to port 1 (this uses that freed HBR2 connection so it will also be limited to 4K)

Now both LG should work? Then you can try single tile 5K39 custom timing.

This is the same technique one would use to connect two 4K HBR2 displays to a Thunderbolt 2 port. The non-LG display needs to be a HBR display, then the HBR2 displays will connect as HBR (so 4K30 or 1440p60 will be the max resolutions).
 
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Ma3n-87

macrumors member
Aug 30, 2008
34
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Ok, so how about this:
1) connect non-LG to port 1 (this takes away one HBR2 DisplayPort connection)
2) LG to port 2 (this uses the remaining HBR2 connection and limits the display to 4K because there's not another HBR2 connection for dual tile 5K60)
3) disconnect non-LG from port 1 (this releases the first HBR2 connection - hopefully the LG won't take it)
4) connect second LG to port 1 (this uses that freed HBR2 connection so it will also be limited to 4K)

Now both LG should work? Then you can try single tile 5K39 custom timing.

This is the same technique one would use to connect two 4K HBR2 displays to a Thunderbolt 2 port. The non-LG display needs to be a HBR display, then the HBR2 displays will connect as HBR (so 4K30 or 1440p60 will be the max resolutions).
How to determine a non HBR2 display? I think this won’t work because as soon as I disconnect the non LG, the LG goes back to allowing 5k. Will try it shortly
 

Ma3n-87

macrumors member
Aug 30, 2008
34
3
Its resolution needs to be 2560×1600 or lower.
Ok, so how about this:
1) connect non-LG to port 1 (this takes away one HBR2 DisplayPort connection)
2) LG to port 2 (this uses the remaining HBR2 connection and limits the display to 4K because there's not another HBR2 connection for dual tile 5K60)
3) disconnect non-LG from port 1 (this releases the first HBR2 connection - hopefully the LG won't take it)
4) connect second LG to port 1 (this uses that freed HBR2 connection so it will also be limited to 4K)

Now both LG should work? Then you can try single tile 5K39 custom timing.

This is the same technique one would use to connect two 4K HBR2 displays to a Thunderbolt 2 port. The non-LG display needs to be a HBR display, then the HBR2 displays will connect as HBR (so 4K30 or 1440p60 will be the max resolutions).
ok so that didn't work but I used the lenovo 4k display (so I need to dig around for another one)

The computer is recognizing both displays. here's the nvidia control panel. I tried various settings thus far without luck. Even the audio is coming out of the black LG monitor now haha
 

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joevt

macrumors 604
Jun 21, 2012
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How to determine a non HBR2 display? I think this won’t work because as soon as I disconnect the non LG, the LG goes back to allowing 5k. Will try it shortly
It can't go back to 5K if you're using a USB-C cable because the USB-C cable is limited to 20 Gbps. When you try a USB-C (non-Thunderbolt) cable with a single display, does it work at least at 4K? Does it have audio with the USB-C cable?

The computer is recognizing both displays. here's the nvidia control panel. I tried various settings thus far without luck. Even the audio is coming out of the black LG monitor now haha
It recognizes both displays but do they both show an image? Or only one? Or none?
What do you mean black LG monitor? You have two LG UltraFine 5K displays which are both black.
If both LG UltraFine 5K displays were connecting properly, then you should be able to change the audio between each one (each display has it's own USB audio device).

I guess this would be a lot easier with the newer LG UltraFine 5K displays because you can use a DisplayPort connection instead of Thunderbolt to force a single DisplayPort connection.

Can you show the Nvidia control panel with the LG UltraFine 5K display connected by itself with a Thunderbolt 3 cable? There should be a tab in the Nvidia control panel that shows connections (not that PhysX tab).
Then repeat that with a USB-C cable.

I thought a normal USB-C cable would be sufficient for your old LG UltraFine 5K displays - it can only carry one HBR2 connection because it will be limited to 20 Gbps instead of Thunderbolt's 40 Gbps.
 
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Ma3n-87

macrumors member
Aug 30, 2008
34
3
It can't go back to 5K if you're using a USB-C cable because the USB-C cable is limited to 20 Gbps. When you try a USB-C (non-Thunderbolt) cable with a single display, does it work at least at 4K? Does it have audio with the USB-C cable?
Yes it does have audio, perhaps these are not pure USB-C cables. With a single LG5k display these cables are supporting (4096x2304) not (5120x2880). I believe it's these that I have


It recognizes both displays but do they both show an image? Or only one? Or none?
What do you mean black LG monitor? You have two LG UltraFine 5K displays which are both black.
If both LG UltraFine 5K displays were connecting properly, then you should be able to change the audio between each one (each display has it's own USB audio device).
I mean it recognizes both displays on the Nvidia control panel but only one screen turns on. What I meant is that the second LG5k display "connects" but doesn't turn on or stays black :) but it connects the audio interface (didn't try to switch the audio between the two sources but I recall that I saw both in the control panel)

I guess this would be a lot easier with the newer LG UltraFine 5K displays because you can use a DisplayPort connection instead of Thunderbolt to force a single DisplayPort connection.

Can you show the Nvidia control panel with the LG UltraFine 5K display connected by itself with a Thunderbolt 3 cable? There should be a tab in the Nvidia control panel that shows connections (not that PhysX tab).
Then repeat that with a USB-C cable.

I thought a normal USB-C cable would be sufficient for your old LG UltraFine 5K displays - it can only carry one HBR2 connection because it will be limited to 20 Gbps instead of Thunderbolt's 40 Gbps.
Yeah I think I need to just bite the bullett and get one of the new monitors, but I only have HDMI not DP as the third connector from the laptop (is there an HDMI out to USB-C/DP in converter ? (I'm only seeing DP to USB-C). I feel like it's a risky investment still and I may end up with another non-working monitor.

Will double check again tomorrow and screenshot the Nvidia control panel. maybe I need to test out other USB-C cables
 

joevt

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Jun 21, 2012
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Yes it does have audio, perhaps these are not pure USB-C cables. With a single LG5k display these cables are supporting (4096x2304) not (5120x2880). I believe it's these that I have

If the cable can do 4K then it's a pure USB-C cable that can also do 20 Gbps Thunderbolt. macOS or Linux can tell you what speed a Thunderbolt connection is.

I mean it recognizes both displays on the Nvidia control panel but only one screen turns on. What I meant is that the second LG5k display "connects" but doesn't turn on or stays black :) but it connects the audio interface (didn't try to switch the audio between the two sources but I recall that I saw both in the control panel)
I suppose you could extract the EDIDs using CRU. Then we can see if the correct DisplayPort connection is being made. Each LG UltraFine 5K can have two DisplayPort connections and each connection has its own EDID. The EDID will indicate the serial number of the display and whether the connection is for the left half or right half of the display. I believe the connection needed for 4K is the left half. If the EDID is for the right half then that would explain why it's not working.
In this case it would be useful to have a utility to setup the correct DisplayPort tunnelling paths over Thunderbolt. Such a utility would have the ability to alter the max DisplayPort link rate in order to accomodate two HBR2 displays over Thunderbolt 2 or two HBR3 displays over Thunderbolt 3 (as Apple does for the Apple Pro Display XDR for GPUs that don't support DSC).

Yeah I think I need to just bite the bullett and get one of the new monitors, but I only have HDMI not DP as the third connector from the laptop (is there an HDMI out to USB-C/DP in converter ? (I'm only seeing DP to USB-C). I feel like it's a risky investment still and I may end up with another non-working monitor.

Will double check again tomorrow and screenshot the Nvidia control panel. maybe I need to test out other USB-C cables
The Club-3d CAC-1332 and similar adapters from SIIG and others converts HDMI 2.0 + USB 2.0 to USB-C.
 
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Ma3n-87

macrumors member
Aug 30, 2008
34
3
I checked the USB-C cables speed in my macbook and got the 20gbps (note they still ran the 5k resolution on mac though). The LG supplied TB3 cable supports the 40 gbps so we're good there I believe
 

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Ma3n-87

macrumors member
Aug 30, 2008
34
3
If the cable can do 4K then it's a pure USB-C cable that can also do 20 Gbps Thunderbolt. macOS or Linux can tell you what speed a Thunderbolt connection is.


I suppose you could extract the EDIDs using CRU. Then we can see if the correct DisplayPort connection is being made. Each LG UltraFine 5K can have two DisplayPort connections and each connection has its own EDID. The EDID will indicate the serial number of the display and whether the connection is for the left half or right half of the display. I believe the connection needed for 4K is the left half. If the EDID is for the right half then that would explain why it's not working.
In this case it would be useful to have a utility to setup the correct DisplayPort tunnelling paths over Thunderbolt. Such a utility would have the ability to alter the max DisplayPort link rate in order to accomodate two HBR2 displays over Thunderbolt 2 or two HBR3 displays over Thunderbolt 3 (as Apple does for the Apple Pro Display XDR for GPUs that don't support DSC).


The Club-3d CAC-1332 and similar adapters from SIIG and others converts HDMI 2.0 + USB 2.0 to USB-C.
The Nvidia control panel allows me to export and load/unload? EDID files for monitors. Here's how it looks when connecting an LG5k and the Lenovo monitor. I exported the EDID of one of the LG5k also and attached here.
 

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Ma3n-87

macrumors member
Aug 30, 2008
34
3
and here is what I get when connecting both LG5k monitors using the USB-C cables (I didn't do the manuever of connecting another monitor first). I exported the EDID files that come with each monitor.

I am able to change the audio source between the two monitors.

I suppose you could extract the EDIDs using CRU. Then we can see if the correct DisplayPort connection is being made. Each LG UltraFine 5K can have two DisplayPort connections and each connection has its own EDID. The EDID will indicate the serial number of the display and whether the connection is for the left half or right half of the display. I believe the connection needed for 4K is the left half. If the EDID is for the right half then that would explain why it's not working.
In this case it would be useful to have a utility to setup the correct DisplayPort tunnelling paths over Thunderbolt. Such a utility would have the ability to alter the max DisplayPort link rate in order to accomodate two HBR2 displays over Thunderbolt 2 or two HBR3 displays over Thunderbolt 3 (as Apple does for the Apple Pro Display XDR for GPUs that don't support DSC).
Is this something that's doable though? perhaps with the Nvidia software?
 

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UltimateSyn

macrumors 601
Mar 3, 2008
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Massachusetts
I don't have much to contribute to this current line of conversation, but I did have a question that I wondered if anyone had thought about; I have an LG UltraFine 4K and have a reservation for a Steam Deck for Q2 of next year... Do you guys think it would be possible to use the Steam Deck's USB-C port to get output to the UltraFine? Would I need hubs / adapters / extra equipment?
 

Ma3n-87

macrumors member
Aug 30, 2008
34
3
If the cable can do 4K then it's a pure USB-C cable that can also do 20 Gbps Thunderbolt. macOS or Linux can tell you what speed a Thunderbolt connection is.


I suppose you could extract the EDIDs using CRU. Then we can see if the correct DisplayPort connection is being made. Each LG UltraFine 5K can have two DisplayPort connections and each connection has its own EDID. The EDID will indicate the serial number of the display and whether the connection is for the left half or right half of the display. I believe the connection needed for 4K is the left half. If the EDID is for the right half then that would explain why it's not working.
In this case it would be useful to have a utility to setup the correct DisplayPort tunnelling paths over Thunderbolt. Such a utility would have the ability to alter the max DisplayPort link rate in order to accomodate two HBR2 displays over Thunderbolt 2 or two HBR3 displays over Thunderbolt 3 (as Apple does for the Apple Pro Display XDR for GPUs that don't support DSC).


The Club-3d CAC-1332 and similar adapters from SIIG and others converts HDMI 2.0 + USB 2.0 to USB-C.
I just got them working! Both LG5k monitors running at 4k each connected by USB-C cables!

What I did was that I exported the EDID file from each of the LG5k monitors, then I chose the monitor that was not working (DP2) and I "loaded" the EDID file of the second monitor (DP1). At first nothing happened. Then I think I refreshed and suddenly both monitors work! not sure how sustainable this is and how it'll work so i'll test it today and let you know

Thanks!
 
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Ma3n-87

macrumors member
Aug 30, 2008
34
3
I just got them working! Both LG5k monitors running at 4k each connected by USB-C cables!

What I did was that I exported the EDID file from each of the LG5k monitors, then I chose the monitor that was not working (DP2) and I "loaded" the EDID file of the second monitor (DP1). At first nothing happened. Then I think I refreshed and suddenly both monitors work! not sure how sustainable this is and how it'll work so i'll test it today and let you know

Thanks!
Correction. what I did was load the EDID file (then nothing happens), then I unloaded the file that I initially loaded, and this is what actually got the second display to work. Once I restart the second display doens't work so I have to repeat this maneuver (?glitch) which is fine

I tried one monitor with the TB3 cable (the LG supplied) and this seems to have taken care of the weird flicker that I get (only with citrix apps), but this has been an ongoing issue regardless of one or two LG displays being used.
 

joevt

macrumors 604
Jun 21, 2012
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I checked the USB-C cables speed in my macbook and got the 20gbps (note they still ran the 5k resolution on mac though). The LG supplied TB3 cable supports the 40 gbps so we're good there I believe
macOS doesn't report the output signal resolution or pixel format. It only shows the framebuffer resolution and pixel format. You can use SwitchResX to view the output resolution and timing. It will say 4K in the case of the 20 Gbps cable. AGDCDiagnose is the only method that can show the output pixel format.
You can use SwitchResX to create custom timings for the LG UltraFine 5K. See if 5K 39Hz works.

The Nvidia control panel allows me to export and load/unload? EDID files for monitors. Here's how it looks when connecting an LG5k and the Lenovo monitor. I exported the EDID of one of the LG5k also and attached here.
That EDID is from the left half of the LG 5K so that's good.

and here is what I get when connecting both LG5k monitors using the USB-C cables (I didn't do the manuever of connecting another monitor first). I exported the EDID files that come with each monitor.
Both EDIDs are from the left half of each LG UltraFine 5K display so I would expect both of them to work. As I originally thought, the maneuver of connecting another monitor first is not needed since the cables are not 40 Gbps Thunderbolt 3 (a non-Thunderbolt USB-C cable can only do 20 Gbps Thunderbolt which only lets one HBR2 DisplayPort connection). Ok, so why then is the second display not being enabled? Is there an option to enable the display in the Nvidia control panel? Maybe the Nvidia driver sees that the displays are tiled displays and is thinking that the second display is the second tile of the first display (that would be wrong since they have different serial numbers and the tile number is the same for each). Maybe if we override the EDIDs with an EDID that has the tile info removed then it would work.

I am able to change the audio source between the two monitors.
That means Thunderbolt is working for both displays since they only support Thunderbolt. PCIe tunnelling is used over Thunderbolt to communicate with the USB controllers in the displays. The USB controllers have a USB hub connected to them. Connected to the USB hub is a camera and audio device and maybe some other stuff (for brightness control). This all can be seen in the Device Manager (view by connection).

Is this something that's doable though? perhaps with the Nvidia software?
It's mostly unnecessary in this case since the displays are connecting properly. Just need to figure out why the second one isn't turning on.

I just got them working! Both LG5k monitors running at 4k each connected by USB-C cables!

What I did was that I exported the EDID file from each of the LG5k monitors, then I chose the monitor that was not working (DP2) and I "loaded" the EDID file of the second monitor (DP1). At first nothing happened. Then I think I refreshed and suddenly both monitors work! not sure how sustainable this is and how it'll work so i'll test it today and let you know

Correction. what I did was load the EDID file (then nothing happens), then I unloaded the file that I initially loaded, and this is what actually got the second display to work. Once I restart the second display doens't work so I have to repeat this maneuver (?glitch) which is fine
Interesting. Seems like a problem with the Nvidia driver.

Anyway, I created an EDID override called "EDID LG5K39 joevt.txt" that you can try. It removes the tile info so it probably can't do 5K60 with Thunderbolt 3 cable? but maybe it will help with the Nvidia driver's confusion. And it adds a 5K39 mode (using CVT-RB timing). If 5K39 doesn't work, then I would use SwitchResX in macOS to test other custom timings. I think I've only ever seen one person try 5K39 and that was with the new LG UltraFine 5K - no one else has reported even trying 5K39 which is disappointing.

I tried one monitor with the TB3 cable (the LG supplied) and this seems to have taken care of the weird flicker that I get (only with citrix apps), but this has been an ongoing issue regardless of one or two LG displays being used.
Not sure what could be going on here. Electrical interference?

I don't have much to contribute to this current line of conversation, but I did have a question that I wondered if anyone had thought about; I have an LG UltraFine 4K and have a reservation for a Steam Deck for Q2 of next year... Do you guys think it would be possible to use the Steam Deck's USB-C port to get output to the UltraFine? Would I need hubs / adapters / extra equipment?
I think it should work. The Steam Deck can output video to USB-C using a USB-C dock. The LG UltraFine 4K is like a Thunderbolt dock that is compatible with USB-C. As a USB-C device (not Thunderbolt) the LG UltraFine 4K expects 4 lanes of DisplayPort 1.2 with USB 2.0. The Steam Deck's dock might be 2 lanes of DisplayPort 1.4 with USB 3.x but if the Steam Deck's USB-C port behaves properly, then it should be able to negotiate a proper connection to the LG UltraFine 4K.
 

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joevt

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and here is what I get when connecting both LG5k monitors using the USB-C cables (I didn't do the manuever of connecting another monitor first). I exported the EDID files that come with each monitor.
Question about the Nvidia control panel, if you connect only one LG UltraFine 5K with a 40 Gbps Thunderbolt 3 cable, does it show both DisplayPorts having a connection with different EDIDs - one for left side and one for right side of the display?
 
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Amethyst1

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Oct 28, 2015
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I think I've only ever seen one person try 5K39 and that was with the new LG UltraFine 5K - no one else has reported even trying 5K39 which is disappointing.
If I ever get my hands on either model, that’s the first thing I’ll try. :)
 

Ma3n-87

macrumors member
Aug 30, 2008
34
3
actually I found out it's the high DPI settings on Citrix. I experimented with various settings (allow high res, show native resolution, allow system to scale rather than Citrix), and I found out I can resolve this issue by using the native resolution (the problem is the text becomes tiny and it's not usable). For some reason this flickering only happens in the Citrix window on one monitor but not both (so I can use it ok if I just move the window to the other monitor). And this only happens with USB-C not with HDMI (and it happens even with a single USB-C monitor). Don't know why

will try the edited EDID files and let you know. How do I force the 5k39 option though (what's the equivalent of SwitchResX for windows? or do you mean make an EDID in SwitchresX on Mac then use the file in windows?
Not sure what could be going on here. Electrical interference?
 

Ma3n-87

macrumors member
Aug 30, 2008
34
3
How do I force the 5k39 option though (what's the equivalent of SwitchResX for windows? or do you mean make an EDID in SwitchresX on Mac then use the file in windows?
never mind I saw you included this in the edited file.
 

joevt

macrumors 604
Jun 21, 2012
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will try the edited EDID files and let you know. How do I force the 5k39 option though (what's the equivalent of SwitchResX for windows? or do you mean make an EDID in SwitchresX on Mac then use the file in windows?
CRU for Windows can create Windows EDID overrides.
https://www.monitortests.com/forum/Thread-Custom-Resolution-Utility-CRU

I don't know if Windows EDID overrides are the same as Nvidia EDID overrides. I suppose you can find out by seeing if Nvidia puts the EDID override in the same Registry location that CRU uses (use RegEdit to view the Registry). Or you can use Monitor Asset Manager moninfo.exe which should be able to list all EDID overrides that exist in the Registry. It should be able to show if Nvidia puts an EDID override in the Registry.
https://www.entechtaiwan.com/util/moninfo.shtm

In Windows, an EDID override is per vendor/product and GPU port. So if you move the display to a different port, then you need to create another EDID override. So its useful to have a copy of the EDID override on disk so you can reapply it when you move the display. You may wish to change the name of the display in the EDID override to include the port that it's connected to.

In macOS, a display override is per vendor/product or per vendor/manufacture date depending on the name of the display override. SwitchResX uses vendor/manufacture date - so it may be possible that a display override created for one display does not apply to another display of the same type if their dates are different. For example, your two LG UltraFine 5K displays are both DisplayProductID-5b11 but have different dates: DisplayYearManufacture-2019-DisplayWeekManufacture-3 and DisplayYearManufacture-2019-DisplayWeekManufacture-4.

A macOS display override does not always contain an EDID override. For example, adding a scaled mode does not require a change to the EDID (and in fact, an EDID does not contain scaled modes). Adding a display timing does require a change to the EDID.
 
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Ma3n-87

macrumors member
Aug 30, 2008
34
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CRU for Windows can create Windows EDID overrides.
https://www.monitortests.com/forum/Thread-Custom-Resolution-Utility-CRU

I don't know if Windows EDID overrides are the same as Nvidia EDID overrides. I suppose you can find out by seeing if Nvidia puts the EDID override in the same Registry location that CRU uses (use RegEdit to view the Registry). Or you can use Monitor Asset Manager moninfo.exe which should be able to list all EDID overrides that exist in the Registry. It should be able to show if Nvidia puts an EDID override in the Registry.
https://www.entechtaiwan.com/util/moninfo.shtm

In Windows, an EDID override is per vendor/product and GPU port. So if you move the display to a different port, then you need to create another EDID override. So its useful to have a copy of the EDID override on disk so you can reapply it when you move the display. You may wish to change the name of the display in the EDID override to include the port that it's connected to.

In macOS, a display override is per vendor/product or per vendor/manufacture date depending on the name of the display override. SwitchResX uses vendor/manufacture date - so it may be possible that a display override created for one display does not apply to another display of the same type if their dates are different. For example, your two LG UltraFine 5K displays are both DisplayProductID-5b11 but have different dates: DisplayYearManufacture-2019-DisplayWeekManufacture-3 and DisplayYearManufacture-2019-DisplayWeekManufacture-4.

A macOS display override does not always contain an EDID override. For example, adding a scaled mode does not require a change to the EDID (and in fact, an EDID does not contain scaled modes). Adding a display timing does require a change to the EDID.
I don't know why this Nvidia is behaving this way. I tried your edited file and it worked great the first go. Even allowed me to restart and both monitors worked. I tried the 5k39 option (it showed up on the monitor connected with USB-C not the TB3 connected monitor). But it didn't work.

after that attempting to load your EDID file no longer works (at least in Nvidia) and I have to do the same thing where I load a file, then unload it for the monitor to work.
 

Ma3n-87

macrumors member
Aug 30, 2008
34
3
I don't know why this Nvidia is behaving this way. I tried your edited file and it worked great the first go. Even allowed me to restart and both monitors worked. I tried the 5k39 option (it showed up on the monitor connected with USB-C not the TB3 connected monitor). But it didn't work.

after that attempting to load your EDID file no longer works (at least in Nvidia) and I have to do the same thing where I load a file, then unload it for the monitor to work.
OK I i got them working again while maintaining the EDID file in effect after restarts etc. But now the audio doesn't work as well (it still loads but buffers intermittently like broken speakers). It was fine all along until all the maneuvers/changes I did. It's happening on both monitors. any ides?
 
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