Dell D6000 - Screen Flickering

[nicola]

Would you have brand and model for the other products you mention?

I-Tec CATRIPLE4KDOCKPD

The HDMI converter and the other dock more precisely.

It is a simple adapter from USB-C to HDMI, sorry but there is not branding, model on the product which I can give you

I wouldn't say the issue would be general to all 3-head docks. For instance, the Dell D3100 has 3 displays through DisplayLink technologt... and if it works for your displays on the Dell D6000 I would expect it to work on the Dell D3100 as well.

I can see that this product is a USB-3 (not type-C), so I can understand that in this case I will not use the USB-C display support but all the video will be managed by the station itself.

You might also wish to try with another refresh rate on the HDMI: this could be enough to stop the flashing/flickering. This is a bit burried in the settings, let me know if you wish guidance on that (if so, tell me the Windows version so I can find a relevant article).

I already tried, but my Windows provides only 60-59-50, and none of them are working (50 maybe is even worse)

My Windows version is 1803.

As additional test, I bought on Amazon an HDMI cable with triple shield, maybe can solve the problem. I will not wait for delivery and test this additional case.

[AlbanRampon]

Thank you Nicola,

The i-tec uses the same principle, and you can see the same 4Kp30 limitation on the HDMI output.

For the Dell D3100, you are correct. This is a DisplayLink only solution. It has a dual-chip design of our previous generation chip. It can do 1x 4Kp30 + 2x 1080p.
The displays are driven directly from the dock output.
The dock isn't a GPU so the computation is still done on the laptop GPU.

Unlike Alt-Mode which doesn't go through standard USB hubs, you can daisy-chain DisplayLink technology. Therefore, you could wish to keep the future-proof aspect of the Dell D6000, and add a single head USB -> HDMI adapter. That adapter could also be useful when travelling or in meeting rooms as well: conference room system input, projector, TV...
Your next machine would have USB-C Power Delivery for charging, and this isn't possible over USB-A.

Kind regards,
Alban

[nicola]

I tried connecting a StarTech USB32HDPRO adapter (USB->HDMI) to the docking station, for the most part of time it seemed to work fine, but one time all the monitor (notebook included) crashed, going all black and turn back on after few seconds. This solution was using 2 monitor connected to the DP ports of the station and one to the USB-HDMI adapter.

But this was made using the USB-C port, so because I will not use the HDMI port anyway, I can try the USB port itself, but maybe it is a throughput higher than supported by a single USB-C port

[AlbanRampon]

This is supposed to work properly.
I'm using a similar setup on my desk: Dell D6000 + Dell D3100, combining the same chips you have. You can switch to USB-A and see if behaviour changes.

There is more than ample bandwidth. We were demoing 8x 4Kp60 at CES last January over a single connection. The dock is dual 4Kp60. A single 4K is 4x FullHD... I'm running out of money buying 4K displays before I run out of bandwidth. The codec we have is adaptative, so even if bandwidth was to become scarce, we would squeeze the data more to make it fit.

The USB-C bandwidth here is identical to the one over the USB-A connection. The dock has a USB 3 Gen 1 hub for 5 Gbps. The reason it's not a USB 3 Gen 2 at 10 Gbps is because it didn't need it and would bring the cost up un-necessarily.

If you keep getting issues, please do use our customer support tool to gather logs (3rd link in my signature). I use the feedback to prioritise bug fixing in new driver/firmware releases.

Kind regards,
Alban

[nicola]

Originally Posted by AlbanRampon

This is supposed to work properly.
I'm using a similar setup on my desk: Dell D6000 + Dell D3100, combining the same chips you have. You can switch to USB-A and see if behaviour changes.

There is more than ample bandwidth. We were demoing 8x 4Kp60 at CES last January over a single connection. The dock is dual 4Kp60. A single 4K is 4x FullHD... I'm running out of money buying 4K displays before I run out of bandwidth. The codec we have is adaptative, so even if bandwidth was to become scarce, we would squeeze the data more to make it fit.

The USB-C bandwidth here is identical to the one over the USB-A connection. The dock has a USB 3 Gen 1 hub for 5 Gbps. The reason it's not a USB 3 Gen 2 at 10 Gbps is because it didn't need it and would bring the cost up un-necessarily.

Maybe it was a coincidence, it has been days that i'm playing with drivers of various components in order to find a working combination.

I will now try to maintain the same configuration for couple of days:
- 2 monitor attached to 2 DP ports of docking station
- 1 monitor attached to USB->HDMI StarTech adapter, attached to USB port of docking station
- docking station attached to USB-C port of the notebook (or USB-A, if is giving problems)
and see what happens...

I will back to you next week with a further feedback.

Originally Posted by AlbanRampon

If you keep getting issues, please do use our customer support tool to gather logs (3rd link in my signature). I use the feedback to prioritise bug fixing in new driver/firmware releases.

I think I already added this log to main message, can you check if the same that you're asking now?


Best Regards

[nicola]

Hello again,
I'm back after few days with some positive news, but not all.

After I tried to the same D6000 station with same notebook but different monitors, I find out that the kind of flickering was different. Sometimes was almost solved, sometimes was really really bad, ...

Because the monitor was working fine with the solution USBC->HDMI adapter (so it was surely the docking presenting the problem) I tried to buy a different cable.
I bought a very high-quality HDMI cable "HDMI 4k 60Hz HDR | HDMI 2.0 a/b | 4K 3D UHD 1080p 3D HFR Ethernet | Full HD 1080p / ARC e CEC"
This cable is triple-shielded and it is certified for 4K. I know I'm using the port at 1080p, but it natively supports 4K maybe can be a hint....

Test 1) Well, with this new cable, the HDMI port of the station is working fine, w/o any flickering (for test1 i connected the dock to USB-C port of the station and only the cable to the HDMI port).

Test 2) I attached the second monitor, to the first DP port of the station (using the previous cable), and now I have 2 monitor working

Test 3) I attached the third monitor, to the second DP port of the stations (using the previous cable), and now the HDMI-connected monitor is flickering again.

This is somehow strange, it does not seem the problem to be to the port itself, but the amount of monitor attached.
Because it seems to a interference of some kind, I bought another 2 triple-shielded cables that I will use for others 2 monitors, and then I will see the result.

I will be back to you next week with this result.
For the moment, the first hint to solve to problem seems to be related to poor-quality HDMI cables.

[nicola]

Hello again,
I received the 3 new cables as mentioned, and for the moment there is no solution.

This is my current scenario:

| ASUS N580VD --> USB-C --> DELL D6000
|
|--------- Station HDMI Port --> HDMI Cable--> Monitor HDMI Port
|
|--------- Rankie HDMI ->DisplayPort 4K adapter --> Docking DP Port --> HDMI Cable--> Monitor HDMI Port

With this configuration, the 2 attached monitor are not flickering, and the third monitor works attached to the HDMI built-in port of the NoteBook.

Adding the third monitor

| ASUS N580VD --> USB-C --> DELL D6000
|
|--------- Station HDMI Port --> HDMI Cable--> Monitor HDMI Port
|
|--------- Rankie HDMI ->DisplayPort 4K adapter --> Station DP Port --> HDMI Cable--> Monitor HDMI Port
|
|--------- Rankie HDMI ->DisplayPort 4K adapter --> Station DP Port --> HDMI Cable--> Monitor HDMI Port

The monitor attached to the HDMI port of the docking starts again flickering.

So, if at start the problem of bad manufactured cables was one of the cause, it is partially solved. The problem now is using both DisplayPort ports of the station.

[nicola]

Hi again,
I'm officially out of ideas.

I also tried buying DP->HDMI "active" adapter (whatever that means) as suggested by some sites and tried the shortest HDMI cable (0.5m).

Always the same behaviour of flickering.

At this point the only working solution is using the 2 DP ports of the station and the built-in HDMI port of the notebook. The USB->HDMI graphic adapter seems to work bad, after some point all the monitor goes black and all windows position are resetted to notebook monitor.

Any thoughts on this?

[AlbanRampon]

Originally Posted by nicola

I tried connecting a StarTech USB32HDPRO adapter (USB->HDMI) to the docking station, for the most part of time it seemed to work fine, but one time all the monitor (notebook included) crashed, going all black and turn back on after few seconds. This solution was using 2 monitor connected to the DP ports of the station and one to the USB-HDMI adapter.

But this was made using the USB-C port, so because I will not use the HDMI port anyway, I can try the USB port itself, but maybe it is a throughput higher than supported by a single USB-C port

I reviewed the thread, and will attempt to summarise.
StarTech USB32HDPRO adapter (USB->HDMI) is using DisplayLink technology as well.
So, from what I can see, when using any of the DL-3xxx, DL-5xxx, and DL-6xxx HDMI outputs, your monitor works properly. You have issues when using the Alternate Mode, and potentially with DisplayPort converter chip.

When all your displays flashed, it could be because of a driver crash. The notebook will blink as you change the desktop layout.
If you still have that adapter, I'd recommend plugging it to your docking station and use it to drive the HDMI monitor.
Should it crash again, we can look into the crash data to improve the driver.

Kind regards,
Alban

[nicola]

Originally Posted by AlbanRampon

I reviewed the thread, and will attempt to summarise.
StarTech USB32HDPRO adapter (USB->HDMI) is using DisplayLink technology as well.
So, from what I can see, when using any of the DL-3xxx, DL-5xxx, and DL-6xxx HDMI outputs, your monitor works properly. You have issues when using the Alternate Mode, and potentially with DisplayPort converter chip.

When all your displays flashed, it could be because of a driver crash. The notebook will blink as you change the desktop layout.
If you still have that adapter, I'd recommend plugging it to your docking station and use it to drive the HDMI monitor.
Should it crash again, we can look into the crash data to improve the driver.

Kind regards,
Alban

Thank you for your suggestions. I tried the StarTech adapter in the previous days, connecting it to the docking station, but also used by itself (only notebook monitor and one external with the adapter) with the USB port of the notebook.
In both cases after some time both monitors get stuck, after few seconds they became all black and the all the layout is resetted (all windows are moved to the internal notebook monitor).

I don't know... maybe the StarTech adapter is damaged, but at this point I'm willing to consider a problem with the Intel driver itself of the notebook, not any external device I can use.