Dell U4919DW / MacBook pro 5k issue

As some users stated that this is an issue only concerning Intel based graphic cards - my experience is different.

I'm using a Mac Pro - Late 2013 with an AMD FirePro D300. Monitor is connected with a DP to MiniDP cable.

If I switch from the Mac Pro to my Lenovo Laptop with Windows 10 (same MiniDP cable) I get the full resolution instantly. Switching back to the Mac Pro it is at 3840x1080.

Contact Apple Customer Service and explain that this model appears to be falling short its advertised specs, and Apple Support has told you its not broken and that's as good as it gets. Be courteous and Professional. Apple wants you to be a Happy customer, if possible.

No it wasn't in the refund window anymore, I bought it a year ago in the Apple online shop. I just contacted Apple tech support, told them about the issue and they said there is nothing they can do then to wait for a Mac OS update that solves the issue. I told them about this thread and that it's unresolved since late 2018 and asked if I could give it back and change it for a MacBook that can actually output this resolution. They asked me where I bought it and told me to contact sales customer support of the Apple online shop and there they let me make the refund. I was really surprised but I think it depends with whom you get connected on the phone and how nice you are to them. And I think they will let you make the refund only if you bought it trough the Apple online shop.

Go to https://support.apple.com/en_US/specs

Type the names of the Macs you want to compare.

The only Macs that will support > 4096 width with a single DisplayPort output (not LG UltraFine 5K or iMac 5K Retina display) with Intel graphics are the ones that support 6K.

That means:

"Intel Iris Plus Graphics 645" (8th gen CPU; I think the tier is called "GT3e") = No

MacBook Pro (13-inch, 2020, Two Thunderbolt 3 ports)

"Intel Iris Plus Graphics" (10th gen CPU with Gen11 graphics; If Apple wanted to be more specific, they could have added "G7" for the tier.) = Yes

MacBook Pro (13-inch, 2020, Four Thunderbolt 3 ports)

MacBook Air (Retina, 13-inch, 2020)

Which MacBook Pro 2017 do you have? Only the two 13 inch models will have the problem. The 15 inch has AMD graphics so it will not have the problem. Since you have left and right ports, you probably have the model "MacBook Pro (13-inch, 2017, Four Thunderbolt 3 ports)".

EDID modification for RGB fix is only needed for HDMI. Are you not using USB-C/DisplayPort?

The Dell display is not a Thunderbolt display, so of course it does not appear in the Thunderbolt section of System Report.../System Information.app. The USB hub of the display and the USB devices connected to the USB hub should appear in the USB section of System Information.app. The ports on the MacBook Pro are Thunderbolt, but the Dell has a USB-C port, not a Thunderbolt port. The cable is USB-C, not Thunderbolt (but it might work with Thunderbolt devices at 20 Gbps?)

The native resolution works because you were running Big Sur. Not because you changed the port. If there is really a difference in the MacBook Pro Thunderbolt ports, then maybe the AGDCDiagnose command can tell you the difference (except it doesn't provide as much info for Intel as it does for AMD). Are you using the same port on the display for each test? The USB-C port of the display, correct? You should test all four Thunderbolt 3 ports.

Consider posting your Big Sur findings/info/tests at

https://forums.macrumors.com/threads/intel-graphics-and-5120x1440-testing-in-big-sur.2244174/

I just installed a 5K Display from another vendor (Philips 499P9) with the same issue. For me switchRes helped to solve the issue. Give it a try (10days free, then 14€). I'm using a MBP15 2018 with Mac OS 10.14.6. And ... It looks gorgeous !

I am using mine on Samsung CRG9 and Odyssey LC49G95T- both are 49" monitors. They were (individually, not separately) plugged in using a Display-Port (DP) from my Belkin dock and DP-DP cables supplied by Samsung. Immediately the M1 MBP recognised the 32:9 factor with 120 Hz & 200Hz refresh rates respectively.

When I accidentally used a HDMI port, the resolution dropped.

I use Switch Res X to confirm and set the monitor settings. It works comfortably on M1 MBP. 'Magnet' which is available from the Mac app store helps in positioning windows on the huge screen. Believe me, you will need some such or equivalent.

I don't have experience with the Dell4919DW, but I would expect the M1 MBP to handle it with ease.

Please keep in mind that the M1 MBP can handle only 1 external display. With a 49" display, only a rare user will want another external display.

Graphics for the 2016 models with 6th Generation SkyLake processors are not capable of Wider than 4096 pixels wide directly, even under Big Sur, without resorting to two interfaces and Picture-by-Picture operation.

Requires 2017 model with 7th generation Kaby Lake or later AND Big Sur to run wider on one interface.

I have the same monitor and issue. I did find a solution that lets you use it clamshell in 30Hz. What you can do is install teamviewer, remote desktop into it (e.g. from an ipad) when the lid is closed, and change the refresh rate. You only need to do it once and it will remember the setting.

Wanted to add that I got a new MBP over the weekend (non-Apple Chip - 13-inch, 2020, Four Thunderbolt 3 ports). It recognized the Dell monitor just fine and is running 60 Hertz.

No roses without thornes: When option-clicking "Scaled", I don't get the 5K2K resolution as an option. The list caps out at 4608 x 1944 although the monitor actually runs the higher resolution; which I set using Resolutionator.

I'm wondering if it would make any difference if we used 2 Moshi Thunderbolt 3 to DP cables, as opposed to 1 Moshi cable and 1 USB-C?

Could you post the Dell Firmware Number?

This IS the solution indeed.

I am am using a 2018 MacBook Pro 15” with the Moshi usb-c to DisplayPort cable and I am able to get 5120x1440 @120hz out of it.

Mac mini 2018 + Samsung CRG90 here. I just tried Catalina Public Beta 1 and 5120x1440 does not work. 3840x1080 is still the max resolution.

Quick question, can you get the full resolution on the screen while the macbook pro's screen is active (ie not mirrored)?

Thanks!