Can't get my 2019 MacBook Pro to recognize my new Dell U4021QW

I'm also seeing this issue, do we know if Apple is aware of this issue? It is looking like a OS issue, since the specs of the Video card has the following listed.

Video Support

Simultaneously supports full native resolution on the built-in display at millions of colors and:

• One display with 5120-by-2880 resolution at 60Hz at over a billion colors

Dell has the following listed

U4021QWThunderbolt 3  90 WUSB 3.0 **5120 × 2160 @ 60 Hz

Hi,

I have the same issue 13-inch 2018 MacBook Pro, using Dell cable the display is identified but no signal detected. Using normal Apple USB-C cable, not even the monitor is detected.

Is this a cable issue, does this work with some other cable with 2018 MacBook Pro? If yes, can you specifically recommend one that works.

How did you find out this information?

Based on my research, the Dell web site says the 2018 MBP should support it.

If it was not supported (as opposed to a sofware/driver issue) OSX should not attempt to run it at full resolution, so hopefully this discussion is of benefit to the commuinity either way.

I have it plugged with the cable to Intel NUC now and can get 3840x2160 out, so cable as such works. NUC doesn't support the max resolution.

This is the MacBook I have:

https://support.apple.com/kb/SP775?locale=en_US

Which says:

• One display with 5120-by-2880 resolution at 60Hz at over a billion colors

When it says one display, do I need to disable the built-in retina somehow?

I had this issue with my almost new Intel i5 2020 MacBook pro. After few weeks of trying and internet-research I concluded that this is a mac issue (hardware or software, don't know) that no-one has been able to solve.

So went and bought a M1 iMac, and everything works perfectly.

Would be great if apple would own up to the issue, but I could not wait.

Yep, I did the same with Disable monitor. I spent 3 weeks trying to support to understand the issue. At the end they provided an answer that pointed at Dell and would not provide it in writing.

I hope you have better luck then me.

I had the problem with Macbook Intel and Dell U4021QW resolution, and solved it by buying a M1 mac mini instead. The Dell worked marvels for a week - but then broke. The picture started flickering, strands appeared and then strong ghost images that suddenly appeared and - strangely - stay after power-off. BAsically the monitor broke down pretty instantly.

So Dell replaced the monitor with a new one. Now, after two weeks, the new monitor broke too, with exactly same symptoms! So it seems that my Mac Mini M1 is breaking monitors. Or is it something with the Dell U4021QW that makes it break with M1 Mac mini. What the **** is going on? Anybody heard of anything like this?

Returning yet another monitor feels strange, but so seems returning perfectly working (with other monitors...) Mac mini too...

Applefantoronto wrote:

... "No Thunderbolt (90W) signal from your device."

Is the monitor trying to pull power as well as video data over Thunderbolt?

tt2

Thanks for clearing up my misconception.

tt2