Dell P3222QE disconnects LAN when 60 Hz active

Question

Level 1

6 points

Dell P3222QE disconnects LAN when 60 Hz active

Hey,

We've bought three identical P3222QE monitors. When connecting my Lenovo P14s running Windows OS, I can easily make it run. I get asked for the settings of always on USB and the increase image quality but reduce network speed.

No matter whether I use better image quality or better network speed, my computer just works flawlessly. 4K 60Hz and 1Gbps.

However, we have two MacBook users (2x MacBook Pro 13" 2019, Two Thunderbolt 3 ports (macOS Monterey 12.6)).

When they connect, they get prompted the same options on the P3222QE. When they choose the "better network", they only support 30Hz, but it seems there are no issues with the Ethernet connection.

If, however, they want to use 60Hz, they have to use the "better image" - and this is where the issue appear. Every now and then, the LAN connection simply drops. No packets are being transferred. Resetting the P3222QE, fixes the issue. Not viable solution.

It appears the macOS loses it lease, and then it self-provides an IP, that is not on our network. It is not related to the router's DHCP lease time, however.

When unplugging the LAN cable, the link is, obviously, interrupted. However, plugging in again, does not fix the issue either.

Unplugging the USB-C -> USB-C cable, does fix the problem, but it not a viable solution to unplug either.

We haven't been able to trace any cause related to the network's DHCP lease. Especially as it works flawlessly on Windows computers.

I seems as if, when choosing the reduce the network speed, to get the 60Hz, the monitor's built-in dock, doesn't forward the traffic and renews DHCP release. Or something like that.

Been looking for firmware upgrades and software upgrades for the P3222QE. Haven't found anything. Tried the two affected P3222QE with my computer, and there are absolutely no problems. So I assume it's some issue between the macOS and the P3222QE.

We've also tested where one of the units has been updated to MacOS Ventura.

We even tested with an ethernet adapter to USB-A plugged in, instead of the Ethernet Port. Same result. It disconnects intermittently.

Anyone got any ideas?

MacBook Pro

Posted on Oct 28, 2022 06:39 AM

Reply

Answer 1

justin_900

Community Specialist

Oct 31, 2022 12:06 PM in response to Tfremlev

Hello Tfremlev,

Welcome to Apple Support Communities!

We want to help resolve the issue so the internet stays connected when using this monitor.

Since it only happens with this particular model, you might check the with manufacturer for more details first: Support for Dell P3222QE | Documentation | Dell US

As the issue might also be related to the network settings, we can check your settings:

"About privacy and security warnings on your device

If your Apple device shows a privacy warning or weak-security warning about a Wi-Fi network, that network could expose information about your device.

If you administer the Wi-Fi network, we recommend that that you update the settings of your Wi-Fi router to meet or exceed the security standards in this article.
If you don't administer the Wi-Fi network, you can bring the recommended settings in this article to the attention of the network administrator."

This Apple Support page has the full details and more steps to take: Recommended settings for Wi-Fi routers and access points - Apple Support

We hope this helps to isolate the source of the issue so you can get the most from the display.

Cheers!

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Answer 2

faith185

Community Specialist

Nov 2, 2022 08:42 AM in response to Tfremlev

Hi Tfremlev,

Rather than manually selecting a resolution, try choosing 'Default for display' from Apple menu  > System Settings > Displays > [Display name]. This may seem like a simple step but as mentioned in Change Display settings on Mac, this will automatically use the best resolution for your display and may help.

Since you are using multiple computers and monitors, this likely happens with multiple cables. Right? If by chance, you're using a shared cable, test another to further isolate where the issue occurs.

If the same continues, it may be best to reach out to Apple Support for a more in-depth look.

Take care.

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Answer 3

Tfremlev Author

Level 1

6 points

Nov 2, 2022 08:02 AM in response to justin_900

Hey Justin_900

The Dell community forwarded me to the Apple community.

We have determined that the issue lies not in the networkconfiguration.

We have furthermore tested with a Macbook Pro 13" 2017 two thunderbolt 3. It also has this issue.

It has been tested (while the two others were away) on all 3 monitors, and it had the issue on all of them.

Myself, I've been using my Lenovo P14s since we got the monitors last 2 weeks ago - I have never had a disconnect.

We've tested with static IPs, without IPv6, with a reserved IP (so DHCP has been removed as a potential cause). We've tested with both newest and previous MacOS.

We are at loss.

Furthermore, a device usually connects to wifi, once a cable is disconnected. Generally laptops prioritize LAN over wifi. What we see is, that when the issue occur, the MacBooks don't automatically use wifi instead. That means the mac does believe it is connected to the internet/lan-cable, but no connection.

Hope you can help me further.

Best regards

Thomas

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Answer 4

EYURYAN

Level 1

8 points

Nov 4, 2022 06:59 AM in response to faith185

Hi Tfremlev,

I am facing exactly the same problem as You described (same monitor model)

MacBook Pro (16-inch, 2019)

It took me a while to narrow down on the monitor as a culprit.

Initially i was disconnecting USB-C cable from MACBOOK side, later found that pressing POWER OFF/ON button (on the monitor/backside) can be used as a remedy (less tear and wear but still ugly not viable solution)

My refresh rate is 60. Switched to 30 Hz -let's see if problem occurs.

P.S.

=> L1 layer is UP;

=> DHCP has nothing to do with the issue (happens for static IP as well)

= > packets are dropped somewhere in the monitor (tcpdump shows them leaving PC )

Reply

Answer 5

EYURYAN

Level 1

8 points

Nov 4, 2022 07:02 AM in response to justin_900

Hi Tfremlev,

I am facing exactly the same problem as You described (same monitor model)

MacBook Pro (16-inch, 2019)

It took me a while to narrow down on the monitor as a culprit.

Initially i was disconnecting USB-C cable from MACBOOK side, later found that pressing POWER OFF/ON button (on the monitor/backside) can be used as a remedy (less tear and wear but still ugly not viable solution)

My refresh rate is 60. Switched to 30 Hz -let's see if problem occurs.

P.S.

=> L1 layer is UP;

=> DHCP has nothing to do with the issue (happens for static IP as well)

= > packets are dropped somewhere in the monitor (tcpdump shows them leaving PC )

Reply