Dell Monitor and MacBook Pro 2021

I just bought a new laptop and cannot connect it with my Dell monitor (Ultrasharp U2415 24.0-Inch Screen LED Monitor).

Could someone offer suggestions on what else I can try.

I tried two different cables (this and this).

I also tried the Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter, and still no luck.

To find the monitor, I go to Preferences > Displays > Option Key > Detect Displays > nothing happens.

Is the Dell monitor simply not compatible with the new Mac?

Edit: My new Mac is MacBook Pro 16-inch, 2021, M1 Max, MacOS Ventura 13.0.

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As a starter it would help quite a bit if you told us the model of the laptop. Assuming it’s an Apple.


Which model of Mac laptop did you buy? (Also, welcome to MPU :slight_smile: )

You might try the troubleshooting guide and self-diagnostics in the manual to your Dell screen, here (p. 58): I would expect it to be plug and play, but cycling through the monitor’s input modes might help.

Are you using a direct connection or a dock? I have intermittent problems running my Dell P2418Hzm off a StarTech dock (connected to a 14" MBP M1 Pro). I’m unsure if it’s the dock, but it seems likely. Sometimes a MacBook cold restart solves my issues and the monitor is suddenly ‘seeing’ the MBP again (or vice versa).

Thank you for the welcome! Sorry I forgot to add that important bit of information.

My new Mac is MacBook Pro 16-inch, 2021, M1 Max, MacOS Ventura 13.0.

It is kind of frustrating trying to figure out the monitor situation because Apple is forwarding me to Dell to solve the issue, and Dell just told me I am on my own because the monitor is old and out of warranty. So I am on my own, and I am placing my hopes in online forums. :frowning:

Plus I am not a tech person though I appreciate technology very much.

Not sure if the new Mac and the monitor are compatible.

MacBook Pro 16-inch, 2021, M1 Max, MacOS Ventura 13.0.

So I do not know what is a dock, which I assume means that I use a direct connection. Basically a cable is plugged into the monitor and into the computer.

In one of the cable setups, I have an adapter, but I do not think I have a dock.

Thanks for the link to the manual.

Hey, nice choice! And welcome to the MPU forum. I don’t know why the monitor isn’t working, but I’ve got to say, the screen on that Mac is way, way better than the Dell.

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I need two monitors and one larger than 16", so that is why I am trying to make them work together. I would love to be able to afford an Apple display, but shelling money for the new Mac was pretty much an investment hopefully for the next decade (fingers crossed).

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I’d try either an HDMI cable, since your Mac has an HDMI port and so does the monitor, or a USB-C to Display Port cable.

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Will do. Just ordered an HDMI cable, hopefully the right kind.

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For your monitor, I think that anything rated as high-speed or better should be fine.

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Kate - unfortunately, I don’t have a solution to your problem. However, I have a Dell P2415Q connected to my 2021 iMac and it works fine. I know it’s not the same monitor you have but I it’s probably similar, so I would think yours should work. Anyway, good luck with it, and welcome to the forum!

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Thanks for the recommendation.

I am checking the prices on Amazon now. I cannot believe that my monitor is currently selling for almost $700. In 2016, I bought it for no more than $250, and I thought it was super expensive.

I know. Mine is $500 now and I paid $300 for it in 2017.

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You need to install the Dell Display Manager. See

As soon as the app is running, the display comes to live.

I‘m using this at work.

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@Kate02_02 Probably the best results would be with a USB-C to Displayport cable for that computer/monitor combination.

One Example: USB-C to Displayport cable at Amazon

You can specify a 3-foot or 6-foot length cable.

Before buying my current monitors I used a similar cable to connect my M1 MacBook Pro to a Dell U2518D monitor that has the same connector options as your U2415 monitor. Worked perfectly, no special display drivers required.

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Over two years ago, I dealt with the same exact issue as you. In the end, I managed to fix it thanks to the advice provided in this topic I created. I hope you might find it helpful!

Ok folks! Thanks for all suggestions. Super grateful for your help. The HDMI to HDMI cable worked. Basically the fourth attempt was the charm. Yey!

If I could only use my old laptop as a monitor as well! The Apple guy told me that I cannot, so I am assuming it cannot happen.

For the person from the future, here’s the cable that worked for me:

8K HDMI Cable 2.1 48Gbps 6.6FT/2M, Highwings High Speed HDMI Braided Cord-4K@120Hz 8K@60Hz, DTS:X, HDCP 2.2 & 2.3, HDR 10 Compatible with Roku TV/PS5/HDTV/Blu-ray