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LG UltraFine 4K and 5K: Yes you can connect it to Windows computers via DP!!!
- Thread starter DeanL
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Right. That's the lower color depth option I was inferring in my first sentence - useful mostly for non-Thunderbolt connections where the GPU doesn't support DSC, such as the RX480, RX580, RX Vega, or Radeon VII.
I just received the Club3D CAC-1331 along with an Amazon Basics Bi-Directionnal USB-C to DisplayPost Cable. I plugged it on my Xbox Series X and my LG Ultrafine 5K (27MD5KL) and the only resolution I have is 720p.
I tried the same adapter (CAC-1331) on my Apple Cinema Display 27 (with mini DisplayPort, not the Thunderbolt one) with the Xbox Series X and I am able to get the full resolution of the screen (1440p).
This would maybe be the solution, but when we look at the specs sheet (https://fsrinc.com/documents/spec-sheet/10505-lit1704b-dr-edid-spec-pdf/file) there is not a lot of different EDID. Just different resolution / frame rate.
Do you know if all Club3D adapter (CAC-1331 ; CAC-1332 and CAC-1333) are using the same chip or not ?
Can we assume that if the 1331 is not working above 720p with the Xbox Series X and LG 27MD5KL, the same will be true for the 1332 and 1333 ?
Is that 720p low resolution or 720p HiDPI (which is actually 1440p)? View the info in SwitchResX. Double click the current resolution to see the pixel clock and active pixels and scale pixels.
There may be better solutions:
https://forums.macrumors.com/thread...ay-thunderbolt-displays.2266864/post-30924390
The "Dr.HDMI 2.0" seems the most capable. You may need Windows to do the EDID modification if it doesn't come with a desired EDID. It may work using a virtual machine.
Probably they will all have a similar problem. Basically, there's a difference in the modes of the LG's EDID and the modes that can be supported by HDMI 2.0. You have to compare the EDIDs that the adapters are presenting to the host with the EDID that comes from the display to see what's happening. I have the EDID for the LG 27MD5KL but not for the adapters paired with the 27MD5KL. I think SwitchResX can get the EDID on M1 Macs now? If you have an Intel Mac, then the EDID included in the AGDCDiagnose output is preferred.
The other issue is what modes from the EDID the Xbox Series X will let you choose. So you'll want to compare the EDID from the adapter with the list of modes presented by the Xbox to see if the Xbox is excluding modes.
The KVM has a DisplayPort to HDMI adapter in order to output HDMI. If you used a DisplayPort KVM then you would be able to get 5K39Hz (maybe your KVM can output 5K but the adapter you use to convert HDMI to USB-C cannot).
The AllRez output show the following:
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allrez - 2560x1440@59.999Hz HiDPI (5120x2880) scaled to 3840x2160.
allrez_4096 - 4096x2304@59.116Hz 138.628kHz 590.000MHz low-resolution (not HiDPI)kConnectionColorDepthsSupported says RGB 6bpc is supported, but that's unlikely, or it's true for the display, but not for the graphics driver. I'm not sure why it doesn't mention any other RGB bpc values. Does the display look like it's being limited to 262144 colors (view a gradient and verify there are 256 different shades instead of just 64 - I suppose you need to make sure to not use an app that uses dithering or it may be that macOS does dithering automatically)? As far as I know, macOS doesn't support 6bpc.
In the allrez_4096 case, there is also a 4096x2304@59.999Hz 142.198kHz 593.820MHz timing. Does that one work as well or does the 593.820MHz pixel clock exceed what is accepted by the LG UltraFine 5K? I believe the limit is somewhere under 600MHz so 593.820MHz might be getting too close.
In both cases, all the scaled modes appear to be based on 3840x2160. If you like 4096x2304 in the allrez_4096 case, then you should change the "Scaled resolutions base" in the Display Information tab for the display in SwitchResX.
Are you having any issues with this new 4096x2304 mode? Is it acceptable? Have your eyes stopped hurting?
@joevt Thank you for your quick response.
It's weird that I didn't do anything else. I think I should use it more to see if my eyes hurt at 4096. However, the font size is too small. I'll find a way to change the font size.
Additionally, I attached the results of allrez on other MBP(2018). The laptop is currently being set to 3008x1692 HiDPI. Could you also analyze this file?
Thank you for your help!
It's weird that I didn't do anything else. I think I should use it more to see if my eyes hurt at 4096. However, the font size is too small. I'll find a way to change the font size.
Additionally, I attached the results of allrez on other MBP(2018). The laptop is currently being set to 3008x1692 HiDPI. Could you also analyze this file?
Thank you for your help!
Set the "Scaled resolutions base" as I suggested to 4096x2304. Then use HiDPI modes that will draw larger text, such as 3008x1692 or 2560x1440. The HiDPI modes will scale down to the scaled resolution base which is 4096x2304.
You didn't answer my question about the other 4096x2304 timing - if it works or not or why it exists.
The EDID changed slightly. It seems each source of the KVM has a different "Source physical address". It may be that the source of the KVM is switchable using software, possibly using DDC/CI (MCCS) but the AllRez utility doesn't know how to do DDC/CI properly in this setup. This is a common issue with DisplayPort to HDMI adapters. Have you tried any DDC/CI software that works?
The GPU in the MBP 2018 is Intel. kConnectionColorDepthsSupported doesn't exist at all here. Another reason why it might not be useful info.
The DetailedTimingInformation does have pixel format information: encodings(RGB,) bpc(8,) colorimetry(NativeRGB,) dynamicrange(SDR,)
which is as expected. HDMI doesn't have enough bandwidth to do RGB 10bpc at 4K.
You didn't add a 4096x2304 custom timing on the MBP 2018. Each source of the KVM needs the custom timing if you want to use that timing with that source.
IOFBTimingRange is interesting. For AMD, you can create timings up to 16K x 16K. With this Intel GPU, the limit is 8K x 3K. For your old AMD, it doesn't say anything about what encodings, bpc, colorimetry, or dynamicrange values are supported (consistent with other info in the AllRez output mentioned previously). For the Intel GPU, that info does exist: encodings(RGB,444,422,420,) bpc(8,10,) colorimetry(NativeRGB,sRGB,DCIP3,BT709,BT2020,) dynamicrange(SDR,HDR10,DolbyTunnelMode,TraditionalGammaHDR,TraditionalGammaSDR,). I think Intel is limited to DisplayPort 1.2 which shouldn't be able to do HDR or 4:2:0 but I guess it's just a simple software switch to enable them. In other words, they don't require hardware features to use.
The mode for the Intel is 3008x1692@59.999Hz 133.317kHz 533.270MHz (HiDPI) scaled to 3384x2160. You'll probably want to create a 4096x2304 custom timing and set that as the scaled resolution base so that the 3008x1692 HiDPI mode (and all the other scaled modes) is scaled to 4096x2304 instead.
Sorry guys if this question has been answered before. I tried to read the entire thread but it's a little difficult for me to follow.
I have a Windows 10 PC. It has an AMD Ryzen 9 so no thunderbolt ports. It has an RTX 3090 FE with 1 HDMI and 3 Display Ports.
I want to connect this PC to an LG UltraFine 5K Display (I forget the model number but out of the box it came with both Thunderbolt and USB-c cables).
What is the best way to connect them? Can I get the 5K resolution? Thank you.
I have a Windows 10 PC. It has an AMD Ryzen 9 so no thunderbolt ports. It has an RTX 3090 FE with 1 HDMI and 3 Display Ports.
I want to connect this PC to an LG UltraFine 5K Display (I forget the model number but out of the box it came with both Thunderbolt and USB-c cables).
What is the best way to connect them? Can I get the 5K resolution? Thank you.
@petervivian: The only way to get 5K60, no matter what model your UltraFine 5K is, is by using a PCIe Thunderbolt 3 add-in card that two DisplayPort outputs of your GPU must be connected to.
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You can't get 5K60 without Thunderbolt, but you can try a lower refresh rate such as 39Hz. Does your PC have a USB-C port that supports DisplayPort Alt Mode? If so, then connect using USB-C. If not, then connect using a Belkin Charge and Sync Cable.
@joevt
However, I kept using it with custom settings, but it doesn't seem to have any issues such as font size and resolution, but my eyes still hurt. I’ll keep checking if there’s any way to improve this in the configuration right now.
For reference, it was used well in TB3 environments without eye pain.
Thank you for your kind help!
This is probably because I have added custom settings using existing information. I'll try to proceed again after initializing the setup.
However, I kept using it with custom settings, but it doesn't seem to have any issues such as font size and resolution, but my eyes still hurt. I’ll keep checking if there’s any way to improve this in the configuration right now.
For reference, it was used well in TB3 environments without eye pain.
Thank you for your kind help!
The motherboard is Gigabyte X570 AORUS PRO WIFI. I looked at its spec and it does not support DPAM. Even newer boards like Gigabyte X570S AERO G only support 4K
"1 x USB Type-C port, supporting USB Type-C and DisplayPort video outputs and a maximum resolution of 4096x2304@60 Hz"
What is a Belkin Charge and Sync Cable?
Thank you.
Found a Gigabyte card, the compatible list says it works with my Gigabyte X570 AORUS PRO WIFI board.
Manual says "2 x Thunderbolt™ 3 out ports (Thunderbolt™ 3 Port 1/Thunderbolt™ 3 Port 2), supporting up to 40 Gbps bandwidth and a maximum display resolution of 8K (7680x3840)@60 Hz"
Does that mean the card can drive the monitor at its native 5k resolution?
Thank you.
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It is 720p low resolution.
I'll investigate with SwitchResX or AGDCDiagnose to see the EDID of the screen.
For information, the chinese guy selling the adapter for Ultrafine 5K and XDR is preparing a newer version of the cable. He told me that by email (huangdash@gmail.com) :
If the scaled modes like 2560x1440 HiDPI are causing pain @ 3840x2160 or 4096x2304, then you should stop hurting yourself. Get rid of the HDMI KVM. Get a DisplayPort KVM. Try 5K @ 39Hz or get a new Apple Studio Display which should be able to do 5K60 with a USB-C connection (only if you have a GPU that supports DSC which the 2018 MBP does not). You could get an eGPU (for Intel Macs only). The Sonnet eGPU Breakaway Puck 5500 XT/5700 should support DSC. They can also support Thunderbolt (if you don't use KVM) for 5K60 on the LG UltraFine 5K.
I don't have experience with AMD APU so I don't know what the real limits are. Maybe it can do 5K at a lower refresh rate?
Google it.
It says it's compatible with rev 1.1 of the Gigabyte X570 AORUS PRO WIFI. Is that the revision that you have? It might work if you have rev 1.0 but maybe not.
Yes, if it works, then you can get 5K 60Hz from it. You need a GPU with two DisplayPort outputs to connect to the Thunderbolt 3 add-in card.
Thanks. I googled "Belkin Charge and Sync Cable" but the results came in pages of ios devices charging cables. I'm interested in what the cable your referred to is capable of doing.
Yes. The revision of that particular motherboard is important. I compared their layouts and found that since v1.1 the board added a 5-pin THB_C header. My board is v1.2 and it has the header that is required to connected to the Thunderbolt PCIe card. I have a RTX3090 and two free Display Ports so I think it's all good. I'll get the card to see if everything works correctly.
Googling for "Belkin Charge and Sync Cable" in quotes gives the following as the first reply:
https://www.belkin.com/us/support-article?articleNum=316883
Googling for
"Belkin Charge and Sync Cable" site:macrumors.com gives results from MacRumors.comIt combines DisplayPort output (up to HBR2 link rate, maybe HBR3 since it mentions 8K?) and USB 2.0 into a USB-C cable that can be connected to a USB-C display.
Let us know how the add-in card works out.
Apologize if this is repetitive but after so much research, I’m still at a loss. I have a pretty limited knowledge of these kinds of things, so please bare with me. Need assistance with my setup that consists of a Dell 5520 (work laptop) and 22” LG Ultrafine 4k display (22MD4KA-B). I’ve used this display over the years with my MacBook Pro and have had no issues. Would love to be able to also use my work computer with it when I work from home. This laptop supports usb-c charging/ display features, so I thought it would be pretty straight forward to connect the two. Problem is, when I do this, I get sound but no image. I’ve researched and researched (even all through this thread) and can’t seem to find a definitive solution to my issue. I’ve seen where a bi-directional usb-c to display port would work, but the laptop only has HDMI. Would a bi-directional cable work in addition to an HDMI/DP adapter? Do I need a docking station? Should I just upgrade to the newer model of the display? Need some expert guidance before I start shelling out money for adapters and cables. Thank you in advance!
I'd rather try a straight HDMI 2.0 to USB-C adapter like this one. The fewer adapters/converters, the better. Do you have a HDMI monitor to test if the laptop is providing video output via HDMI?
Going back to the straight USB-C connection for now:
1. Are you using the same USB-C cable that works in conjunction with your MacBook Pro?
2. Is the monitor being detected in Windows' display properties at all? If so, is Windows set to expand the desktop to the monitor?
3. Have you tried playing with the Intel graphics driver's settings panel to see if the monitor needs to be enabled manually (shouldn't be necessary but you never know...)?
4. Do you have another DisplayPort or USB-C monitor to test if the laptop is providing video output via USB-C in the first place? It is not impossible that this has been disabled, either through an UEFI firmware setting or other setting, by your employer.
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