Dell U4919DW / MacBook pro 5k issue

So here's an interesting twist. According to this page, the MacBook Pro 2016 and later is compatible with the 27-inch LG UltraFine 5K Display. Here's what's interesting. I emailed LG and asked whether that particular monitor was SST or MST. And they replied that it is SST. So apparently not all SST monitors are created equal. Wondering whether I missed a small detail, or whether Apple chose to override the SST limitation and make it compatible with this specific LG monitor. See their email below...

Dear Valued LG Customer,

Reply to Your Inquiry

Hi John, we highly value your overall experience to be as seamless as possible. I am more than happy to assist you today. Let me provide the right information that you need about your inquiry. We have checked our support system and the 27MD5KA-B is SST monitor. Thank you, John. Have a great day! 

I hope this information has been helpful in addressing this matter. Should you have any further inquiries or clarifications, please do let us know and we'll be glad to help out. You may contact us again via Email, Live Chat, or Phone by calling 1-800-243-0000. 

Thank you for contacting LG. 

Sincerely yours, 

Belle 

LG Email Department 

Toll Free number: 1-800-243-0000 

LGEAI | Customer Interactive Center 

Monday- Sunday

Hi Everyone,

I just purchased a Mac Mini 2018 and Dell U4919DW Ultrawide Monitor, and like others here, I can't get video resolution out of the setup. I tried using the included USB-C cable and HDMI cable included with the monitor, no go. I do get high resolution when connected to my PC via Display Port Cable however so the monitor itself is working.

I called Dell, and their technical support was a complete joke. The lady on the phone basically said "If it works on a PC, it works", and wouldn't lift a finger to provide me with any ideas or suggestions, and refused to escalate the call to someone who knew the differences between cable types (She didn't).

I called Apple and the tech, David, tried alot harder, easily spending about 20 minutes with me trying to find the problem. (Apple tech support is why they always win my business). He was not able to solve the problem but has created a case # and escalated this to Apple Engineers. By Apple and Dell's own documentation, I should be able to get 1440 lines of resolution in my setup.

I ordered at USB-C to Display Port cable from Amazon which I should get tomorrow. Hopefully this will work.

If Apple is unable to fix the issue quickly enough I guess we'll just have to wait for the next OS Update. This sucks because I am LOVING my new Mac Mini and U4919DW Ultrawide. I just need the resolution to be what I am used to (I was using dual iMac 27" in shared desktop mode - loved it).

Anyway - Hopefully the Apple Geniuses will come up with a solution to this soon.

Technically, the Dell is compatible as well since you can use it as two-screens-in-one like Mark suggested, but for the premium price we're paying today for both Macs and those high-end monitors, it's absurd we have those kind of compatibility issues. At those price points everything should just work out of the box.

I wouldn't hold my hopes up for the other 32:9 monitors, this is an issue Apple (and Intel, likely) have to sort out themselves.

Actually, I'd love if someone could get in touch with Intel and explain our current issue. I think that Apple doesn't write the video drivers themselves, so instead of pestering Apple, maybe we should start asking Intel to look into Apple's video drivers.

Yes it's better to have a AMD graphic card to avoid such problems.

i'm working in audio post prod so a dedicated graphic card is not what i need. And i would not pay gor a eGPU just to have the right resolution on this display. However it seems that people who booted windows 10 in native mode get the full resolution.

So it's only a software problem (macOS) and i'm waiting for Apple to provide a solution.

The Philips 499P9H 49" SuperWide Curved Monitor is now available on Amazon. Perhaps this will resolve compatibility problems. It's also cheaper than the Dell monitor at $1,300.

https://www.amazon.com/Philips-499P9H-SuperWide-Monitor-5120x1440/dp/B07MCMFRK8/ref=sr_1_1?ie=UTF8&qid=1550246242&sr=8-1&keywords=499P9H

Here's a couple of observations/statements whilst were waiting for others above to update.

I have a Mac Mini 2018 and the Del U4919DW.

I previously had it connected in PBP mode, one connection via USB-C, the other via the HDMI port. In this configuration the display does not sleep correctly (ever). For whatever reason the combo of the USB-C and HDMI in PBP means that the monitor does not sleep and that you have to power it off manually. Following some of the updates above (and with particular thanks to @Mark from 2Much) I swapped the HDMI out for a USB-C to DP cable. This resolved the sleep issue.

So, I now have 2 x (2560x1440\0displays running in PBP mode.

I am yet to try SwitchResX but may do at some point (the dual display works well for me, same as others have expressed above).

Ok ok ok, I got some news.

I basically went on elemination round excluding stuff and eventually came to the following conclusion:

When I put the integrated USB of my 499P9H into USB3.0 mode, then I'm limited to 5120x1440x30hz.

When I put the integrated USB into 2.0 mode, then I can select up to 70hz!

This is all on my Macbook Pro 15" (2017) model. Using the included USB-C cable, Macbook is in clamshell mode.

I installed Windows using Bootcamp and it recognize U4919DW as 5120x1440,

Windows does not "recognize" display resolutions. It simply lets you set whatever you please. If your display is damaged because of that, it's your own fault for setting it so high.

Historically, the Mac has a better track record of working with displays because it sends a query, "What is your name and what are your capabilities?" The Mac then provides settings based on the device's stated capabilities.

But modern displays have more obscure capabilities, and BOTH display developers and the Mac have been slow to 'get on the same page' about what those numbers really ought to mean.

I doubt it is going to make a difference since Dell only tests on Windows, but has anyone tried updating the monitor firmware with the version that was released late last week? It's a little tough for me to test because the update tool is Windows-only.

https://www.dell.com/support/home/us/en/04/product-support/product/dell-u4919dw-monitor/drivers

The driver details don't indicate any fixes that sound particularly promising...

Leo,

Since you have mostly isolated the problem, I finally ordered this beast for myself (been monitoring this thread for a long time). So I'll be down to help when I get this thing delivered on Wednesday. I was going to order some cables to run it in PBP (probabbly 1 usb-c to DP, and one regular hdmi cable (that I can run through my macbook dongle) until we can use a single just a usb-c. I'm happy to order something else if you get back to me by Sunday night/Monday morning. Do you have a Git going for what you're trying to pull off with your EDID stuff? Lemme know, we can work on trying things out!

I contacted Dell support today and asked the following question: Does Dell U4919DW monitor work with a 2019 MacBook Pro with a Radeon Pro 560X graphics card? I saw on some forums that that are connectivity issues but I don’t know if there is a fix for this. The response was:

"Yes you can now easily connect that Monitor to Macbook pro 2019 and to get best resolution it is recommended to connect it through a Display port."

I followed with the question: To clarify, if you connect through the display port then you can get 5120 x 1440 resolution. Also, I assume this will not work through the USB-c port--correct? The response was:

"Yeah that's correct!"

So, I am wondering if this is correct. Has anyone tried this? Will connecting through a display port have any negative effects on performance of the monitor.

I was on the phone with apple. I'm not very optimistic that this person will be able to help me. I'm expecting a call at 6:30 tomorrow EST. In the extremely unlikely event that this person provides a fix I'll post it here.

In the mean time this is a lot like the issue I was having w/ my previous LG getting res 3440x1440. At the end, someone created an overlay that I used. Apple never did fix the problem.

This looks very similar to what I had to do before:

https://comsysto.github.io/Display-Override-PropertyList-File-Parser-and-Generator-with-HiDPI-Support-For-Scaled-Resolutions/

Retrieved from this post: https://www.tonymacx86.com/threads/adding-using-hidpi-custom-resolutions.133254/page-77#post-1907311

If a brave soul has luck w/ this please let me know.

After sending a macOS Catalina beta feedback with multiple screenshots and explanations with the same issue with the same monitor, my Feedback was updated to Potential fix identified.

Hopefully it will be solved and we can have a full resolution with new OS.

I went half way there, but did not want to disable system integrity protection. What I can share is, there are no overrides for the LG 49BL95C-W or DisplayProductID 9e7b. Quite simply, this monitor is not supported in macOS 10.14.6 as we all know and just defaults.

Those with the Catalina Beta, check the path below and see if and DisplayProductID files end in "9e7b".

/System/Library/Displays/Contents/Resources/Overrides/DisplayVendorID-1e6d

<<did not want to disable system integrity protection. >>

You would need to disable System Integrity Protection only long enough to install the modified file, which (at this writing) is in a protected directory. Once the modified file is installed, System Integrity Protection can be restored to its normal ON state.