Dell U4919DW / MacBook pro 5k issue

joevt wrote:

The work-around is to create an override that sets DisplayPixelDimensions manually or using SwitchResX, similar to the file in /System/Library/Displays/Contents/Resources/Overrides/DisplayVendorID-1e6d/DisplayProductID-9e7b for Catalina.

The following script lists all overrides that use that property:

for thefile in $(grep --include 'Display*' -l -r DisplayPixelDimensions /System/Library/Displays/Contents/Resources/Overrides/ ); do

printf "%s " "$thefile"

eval $(plutil -p $thefile | grep DisplayPixelDimensions | sed -E 's/.*0x(.{8})(.{8})}/echo $((0x\1))x$((0x\2))/')

done

The work-around doesn't work for Intel graphics because macOS Intel graphics drivers do not support resolutions wider than 4096. Macs in the future that use Ice Lake (10th gen Core CPU with gen 11 graphics) will probably not have that limit.

So what you're saying is the problem is the MacOS graphics driver, because I can get the full resolution on my MBP 13", that has an Intel Graphics card, if I boot to Windows.

I spoke with Apple today, they refused to replace my Macbook Pro with the same issue! I was told that I should have checked compatibility with Dell and referenced a knowledge base article (https://www.dell.com/support/article/en-uk/sln314416/dell-u4919dw-system-requirements-and-supported-configuration?lang=en)!!

I was also told that the support mentioned on the Macbooks Pros tech spec is OK:

The Macbook Pro can support the above resolution but it can't support certain lower resolutions such as 5120-by-1440. I find that incredibly misleading!!

So all I can do is either return the monitor or purchase a new Macbook Pro with newer CPU that supports the resolution and work out what to do with the slightly older Macbook Pro.

Gutted.

Ref : Cable Matters Cable Displayport USB C (Cable USB C Displayport/Câble USB C to DP) 8K 60Hz Black 1,8m - Port Thunderbolt 3 Compatible MacBook Pro, Dell XPS 13/15

I can't find it on Amazon.com, I'm in France, so here's the .fr link :

https://www.amazon.fr/gp/product/B01LYD2Y19/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

The most important here is the 8K 60Hz, this is the 1.4 DP. I tried 3 cables, 2 hdmi (cheap and "high end") and this cable, and only this cable is able to display the right resolution

Reread the thread. We already know all this. And Apple is fixing it in Big Sur but only for Kaby Lake and Coffee Lake. They could fix it for other Intel GPUs but they won't. They could fix it for older macOS versions but they won't.

Here's a summary:

The problem for older Intel graphics (not Ice Lake) on macOS prior to BigSur with 5120x1440 displays is the width because Apple disallows width > 4096 even though width > 4096 works in Linux and Windows.

As for pixel clock, it doesn't matter because you can lower the pixel clock by using a timing with a lower refresh rate.

The chatter here is that Big Sur is a requirement to go wider than 4096 pixels wide.

(and only supported for 2017 and later MacBook Pro, which you have).

I just got home with a Blackmagic eGPU and plugged it into my Mini 2018, and the monitor works properly, 5120x1440, no lines, just one cable- USB3 that came with the monitor.

So if you’re using a 13” MacBook Pro this will work for you, granted you’ll be spending another $700 like I did.

For what it's worth, I have it working at 5120x1440 with a 15" MBP 2017 when using the latest CalDigit hub which has a DisplayPort (and then connects to the MacBook via USB-C.

There are periodic issues that occur when waking from sleep, including:

* Sometimes the display switches into mirroring mode when waking from sleep

* Sometimes the display does not detect a signal

* Once in a while macOS forgets that it can display the monitor at full resolution and lists 3840x1080 as the maximum

For me, all of the above issues are resolved by unplugging and replugging the USB-C cable between the hub and the MacBook.

The current work-around is still using the PBP mode and connecting two cables to the Mini or the Macbook Pro, one with USB-C, the other with USB-C to DP. Both DELL and Philips support PBP. This will give you two monitors with 2560x1440. You also have to switch off the "Monitors use different Spaces" mode in "Mission Control" to prevent windows from being cut while moving them to the center ofthe screen.

As far as I understand this issue, Apple limits the pixel frequency to about 250 MHz which is enough for 3840x1080@60Hz or 5120x1440@30Hz. I tried different custom resolutions with SwichResX and nothing works above this 250 MHz. For 5120x1440@60Hz you need 442 MHz. But as we know from Bootcamp users, it's a macOS software limitation.

All this discussion about what port may support the display is pretty useless as it's obviously just a software issue. Booting into Windows with Bootcamp makes the display work with any connection (USB-C alt mode or adapter). Apple just needs to push a proper fix for the (at least Intel) driver. It could be possible that several adapters with their own drivers or also the Radeon GPU can already work with that display, but thats not because of a hardware capability but just because of a functioning driver.

If you want to stay with your 13" MBP / Mac Mini 2018 - yes, it is.

And it is an Apple driver issue, not one of the Intel Graphics chipset - on the same machine it works flawlessly with Windows 10 with 5120 by 1440 oob.

JeanLuc7 wrote:

If you want to stay with your 13" MBP / Mac Mini 2018 - yes, it is.

And it is an Apple driver issue, not one of the Intel Graphics chipset - on the same machine it works flawlessly with Windows 10 with 5120 by 1440 oob.

I just received a moshi USB-C to DP cable. I tried it with my USB-C thunderbolt cable w/ my 2018 13" MBP and I could not get resolution 5120 x 1440. It did now show the resolution 2560x1440. It would only show 3840 x 1080 for both monitors. I'm not sure what I did wrong but I could not get that work.

marino389 wrote:

Can anyone confirm this for me?

I'm looking at purchasing a MacBook Pro that will be compatible with the U4919DW monitor. I want it to work properly without any "workarounds." Full resolution out of the box. My understanding from this thread is that it must be a dedicated graphics card instead of the integrated one.

I talked to Apple sales today and I was told that ALL 13" MBPs (without exception) have integrated cards. And that ALL 15" MBPs (without exception) have dedicated cards. I was also told that you cannot customize a 13" to have a dedicated card.

Is this correct?

If you want it to just work you will need to purchase a 15" MBP. It will work without problems. It does not work directly with a MBP 13", for no other reason than Apple will not create a display overlay for it. It works just fine w/ a MBP 13" running Windows 10. So its MacOS not the hardware.

I update my MacBook Pro 15" with Catalina and now I can choose 5120*1440 in the setting. Before, I used ResXtreme but now it's like working without the app.

But there is not a difference in quality between before with the application ResXstrem and now via the native settings.

On my Macbook Air 2018 the Problem still persists with Catalina 10.15.1. The maximum resolution with the thunderbolt cable is still 3840x1080 but under Windows Bootcamp I get the full 5120x1440. Please apple, fix it. It's annoying not be able to use the real resolution.