External Monitors Flickering Off and On

[ThisIsUnique]

Hello, hoping someone can provide assistance for a really annoying issue we're encountering in our environment thats affecting multiple people with different set ups accross different locations

We have the following we provide:

HP ZBook Fury 15 G8 Mobile Workstation PC as well as G10

HP Thunderbolt Dock 280W G4

The issue is, when running external monitors through the docking station, they will randomly turn off and on (i.e. go black) which can change in frequency, from multiple times per hour to few times per day, however when remoted on or they're sharing their screen, the screen still displays fine and there is no disconnect sound being experienced. The screen is still turned on in the remote session which does not suggest a power or disconnect issue.

This issue happens across multiple different models of monitors, however we do have HP E24 G4 that we replaced for a user, as well as the cables and the issue is still occurring. We've also tried with an HP USB-C Dock G5 for the same user, and issue is still occurring.

We've updated all drivers and BIOS to their latest version, as well as the firmware of the docking station, we've checked the screen refresh rate to match all screens and set to a whole number (60Hz and not 59.997), and nothing. We've tried to disable MTSDC via registry changes, as was suggested by a different forum post where they've engaged Dell and this was the fix for them, and nothing. I've also tried disabling thunderbolt mode in the BIOS as well as enabling high resolution when in DP Alt mode, nothing. I disabled G-Sync in NVIDIA control panel and forced it to always use the on-board GPU for its processing however this did not make any effect and made things worse for one of the users.

The models of monitors can vary, they could either be Phillips, Lenovo or HP however they do not support updating its firmware, besides the HP which we haven't actioned yet and doubt it will make any difference. 

We've engaged HP in the past regarding this, and tried downgrading specific drivers, BIOS versions and still nothing. HP does not want to take further ownership as the factory HP OS is not being used (which no one would use in their business environment anyway) as we are using Microsoft Enterprise builds. 

So far, we've only found that this issue does not occur when running screens either through the dedicated HDMI slot, or thorugh the USB-C port using an adapter, issue is only occurring on external displays (could either be 2 or 3 depending on the user) and when its ran through a docking station (can be any type or brand, we have both HP and Lenovo).

The business is not going to be happy with having adapters or screens run through the port as the solution for this, as the expected interaction is a docking station should be able to display screens and connect accessories as it was its intended purpose.

Has anyone run into this before and have any other suggestions we haven't tried yet?

[ThisIsUnique]

I should mention that DisplayLink Manager is also up to date

[Sully618]

I had this issue for a long time.  HP ZBook Fury 16 using a HP USB-C Essentials dock, projecting to three monitors (2x DP, 1x HDMI).  An update to the dock's firmware finally cleared it up.  

Something about 12th gen processors "miscommunicating" with the docking station.  

[ThisIsUnique]

Hi Sully,

Thank you for your post. Unfortunately, I've tried this already. For all 3 users who I have tickets for I've forced a re-install of the latest docking station firmware and unfortunately has not made any difference. This same issue also happens on other docking stations we've tried (Lenovo dock of some kind, and a HP USB-C Dock G5). This model is also an 11th Gen processor btw

[Jupitero]

Hello.

I presume you also tried the very latest BIOS 1.18, dated Sep 20?

Does using HDMI (instead of DP) with the dock make any difference? Do all external monitors go black at the same time?

Are you using grounded power outlets for all IT equpment? The current flow in ungrounded setups may cause problems.

Have you ruled out interference by an outside EMI source? I've had a couple of cases where some heavy machinery distorted analog VGA signal and caused blackouts in digital video signals. This could be an elevator, washing machine/whatever sufficiently close-by.

I understand that the preloaded HP branded Windows was wiped (or upgraded) to Win Ent, but if you could indulge the HP support person and swap the SSD for one with the preloaded Windows so the support person can escalate this if/when the problem does not go away. If the problem does goes away it's a software/driver issue.

OR, if you boot the laptop into BIOS or Diagnostics screen, does the external display show the screen? (There may be a BIOS setting for primary display output). If external monitor works, keep monitoring it - white screen(s) flashing into black for a moment should be quite visible even if you're not actively looking at it.

[DK_IT_01]

There is no fix yet. I have been working with HP tech support for awhile and unfortunately the case has moved no where. I even sent them an affected unit but they said they couldnt reproduce the issue ... my users however continue to run into the issue several times a day, every day. WIth that being said, the case is still open and my HP agent said more reports of the issue have been coming in and the R&D team is working with both NVIDIA and Intel about the flickering. 

I have 34 Zbook fury laptops across several clients. Zbook Fury 16 G9 through G11

and HP docking stations ranging from G2 G4 and G5 docks. 

Also, I did not have luck using USB-C to DP port adapters from my docking stations. Are you saying they worked for you?

So far the only fix that my clients have been able to find is ditching their expensive HP docking stations for alternative brand docks. 

https://h30434.www3.hp.com/t5/Business-Notebooks/External-Monitor-s-Flicker-G4-Dock-NIC-crashes/m-p/...

ALSO 

Intel Ethernet Controller l225

If your laptop has this NIC in Device Manager \ Network Adapters - be aware that the newer drivers will crash all the NICs and a hard reboot will be the only fix. I have found going back and installing an older softpaq from March 2022 resolves the issue .. until updates happen 

SP139326 has the driver from 3/2022 that resolves the network crashing issue 

HP said this could help https://www.realtek.com/Download/List?cate_id=585 but I honestly haven't tried it. 

[Jupitero]

Hi again,

Also, I did not have luck using USB-C to DP port adapters from my docking stations. Are you saying they worked for you?

No, I do not have the 280W TB Dock so can't confirm. The 280W Dock's documentation states that "The lower DisplayPort port and USB-C 3.2 Gen 2 DisplayPort port are mutually exclusive. Only one may be used at a time."

Make sure you adhere to that rule. Presumably you've verified your USB-C to DP adapter is functioning when plugged straight to some laptop?

So far the only fix that my clients have been able to find is ditching their expensive HP docking stations for alternative brand docks. 

Oh, I understood that you replicated the problem with other docks as well when you originally wrote this. My bad.

"...issue is only occurring on external displays (could either be 2 or 3 depending on the user) and when its ran through a docking station (can be any type or brand, we have both HP and Lenovo)."

In any case, good luck, and hopefully you will see your case come to its fruition.

[DK_IT_01]

Oh, I understood that you replicated the problem with other docks as well when you originally wrote this. My bad.

- I did replicate with other docks. They were just other HP docks. Two versions of the G2 dock and two users on G5 docks.  The G5 problem wasn't as wide spread but those affected users/companies ditched their HP docks ASAP so I never really had the chance to confirm how wide spread the issue was for them. 

HP Thunderbolt Dock G2 with Combo Cable

HP Thunderbolt Dock 120W G2

HP USB-C Dock G5 

Make sure you adhere to that rule. Presumably you've verified your USB-C to DP adapter is functioning when plugged straight to some laptop?

As far as the USB-C to DP adapters, I used just one of them and a DP cable. Ive also used a single HDMI and DP cable. Ive trieid DP to DVI adapters. A few different standards of USB-C to DP straight cables. Whatever cables combo I have thought to use has no solved the flickering issue. I also verified the cables I had all worked via other methods. I have other Zbook models floating around and while they can have flickering issues, its not a guarantee that they will flicker

HP Zbook Firefly

HP Zbook Studio

[SergV]

I have the same issue with Dell display which has integrated Thunderbolt Dock station. Problem appeared week ago. I have found many complaints to support about it, but I haven't found any solution. There is only dumb recommendations to check cable or reinstall drivers. Of cause I did all of them before coming here.

[Jupitero]

Hello SergV,

While the symptoms may be the same, the flickering can be caused by some other thing. Do you have the same laptop model?

Did some update happen a week ago when your problem started? GPU drivers or BIOS automatically updated, for example?

Check the Dell support website for a firmware update for your monitor.

Also check your laptop download page for BIOS and/or Thunderbolt controller firmware updates. The GPU drivers are also play their own part, check for updates from HP/Intel/Nvidia/AMD as well.

Try using another Thunderbolt PC/laptop or another Thunderbolt cable. If the same problem still manifests itself, then it obviously is either the Thunderbolt cable or monitor at fault.

Monitor drivers (.inf) are next to useless, but checking the cable for any damage is a sound advice. Keep in mind that damage from e.g. bending/twisting the cable too tightly or due to fault in soldering may not show visually or cannot be felt with fingertips.