WD19TB - 7490 - Dual 4k at 60hz - Impossible?

Dual 4K 60Hz is not possible through the DisplayPort outputs on the Dell WD19TB dock. This I find odd to say the least as it's a step backwards from the older Dell TB16 dock with which you could get dual 4K 60 Hz via the DisplayPort outputs.

To get dual 4K 60Hz you'll either need to:

1. Buy a notebook that supports HBR3 (very niche right now)
2. Buy a USB-C to DP adapter to workaround this (your mileage may vary)
3. Buy a dock that supports dual 4K 60Hz without needing to do 1. or 2. such as the Dell D6000 https://www.dell.com/en-us/shop/dell-universal-dock-d6000/apd/452-bcyt/pc-accessories

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@decker12 wrote:

I picked up one of the new WD19TB Dell docks and hooked it up to a nearly-new 7490 with TB3. I tried every combination of HDMI and Diplayport (WD19TS has dual DP and HDMI, my monitors have both DP and HDMI) and cannot get this dock to talk to my 4k monitors at 60hz. They only go as high as 30hz.

I have a Caldigit TS3+ dock which hooks up to this same 7490 via TB3, and runs dual 4k at 60hz without a problem. I just can't get the new Dell WD19TB to do it. What am I doing wrong?

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Hi @decker12 according to the WD19TB spec sheet the system will support dual 4K monitors @60Hz on the conditions that the laptop is connected via Thunderbolt, not USB-C. The USB-C systems won't support that config.

The caveat to using thunderbolt is that in order to run dual 4k 60Hz one of the monitors has to be connected to the dock via USB-C. Here's the link to the spec sheet, notice the 2* next to the 4K dual display and the following footnote for it - ** Requires one (1) 4K display connected to the TBT3 USB-C interface

https://www.dellemc.com/resources/en-us/asset/data-sheets/products/electronics-accessories/dell_thunderbolt_dock_wd19tb_spec_sheet.pdf

Alan

Thanks for the info @Anonymous and @jimaah . Our 7490's do have TB3 (not just USB-C) so it's connected to the dock properly via TB3.

I noticed on the back of the dock there is a USB-C connector with a DisplayPort logo on it. Is that the port I need to use?

That being said, my LG monitors only have the large DP connector and HDMI. Do I just get a cable that converts DP to USB-C, and then use HDMI for the 2nd monitor? Or do I need something special other than a converter cable to make that happen?

Another question: The LG monitors I am using have HDR built into them, something I don't need to use. Any chance that is causing problems with the TB3 bandwidth?

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@decker12 wrote:

Thanks for the info @Anonymous and @jimaah . Our 7490's do have TB3 (not just USB-C) so it's connected to the dock properly via TB3.

I noticed on the back of the dock there is a USB-C connector with a DisplayPort logo on it. Is that the port I need to use?

That being said, my LG monitors only have the large DP connector and HDMI. Do I just get a cable that converts DP to USB-C, and then use HDMI for the 2nd monitor? Or do I need something special other than a converter cable to make that happen?

Another question: The LG monitors I am using have HDR built into them, something I don't need to use. Any chance that is causing problems with the TB3 bandwidth?

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@decker12 that is correct regarding the port. This is the link to the Ireland website but it will give you an idea of the adaptor you need and the part number - https://www.dell.com/en-ie/shop/dell-adaptor-usb-c-to-displayport/apd/470-acfc/tvs-home-theater

I can't honestly say if the HDR feature would have an impact on the TB3 bandwidth, however if you connect up the displays as described for 40Hz I shouldn't then see there being a problem with the bandwidth. Have you tried disabling HDR from the monitor menu?

Alan

Thanks @Dell-Alan D 

Is there something special about that adapter? I ordered a cable from amazon that was USB-C and DP, and said it was 4k @60hz. Link is here:

https://www.amazon.com/gp/product/B01N11K30W/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

I'm hoping that's the equivalent of that Dell adapter, both because I already ordered it, and I'm not a fan of propriety adapters. 

I also noticed the TB3 cable is longer on the TB19TS. Any idea why/how it's longer than what was shipped with the TB16s? I was told in the past that the TB16 cable was so short because of limitations of power delivery.

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@decker12 wrote:

Thanks @Dell-Alan D 

Is there something special about that adapter? I ordered a cable from amazon that was USB-C and DP, and said it was 4k @60hz. Link is here:

https://www.amazon.com/gp/product/B01N11K30W/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

I'm hoping that's the equivalent of that Dell adapter, both because I already ordered it, and I'm not a fan of propriety adapters. 

I also noticed the TB3 cable is longer on the TB19TS. Any idea why/how it's longer than what was shipped with the TB16s? I was told in the past that the TB16 cable was so short because of limitations of power delivery.

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@decker12 it's the official Dell one which has been tested and guaranteed to work on your system. Whilst the third party cable should work, we can't guarantee it will.

The cables are now interchangeable depending on how much performance you require from the dock. The dock itself doesn't change now and the cables can be upgraded. They have designed it to be future proof. More info can be found here - https://www.dellemc.com/resources/en-us/asset/data-sheets/products/electronics-accessories/dell_thunderbolt_dock_wd19tb_spec_sheet.pdf

Alan

Thanks for the update. I have purchased the WD19TB which according to the PDF, should also be charging my 7490s. Is the "WD19TB" the same base unit as the other WD19's, but just with a different cable side-box coming out of it?

I'm still curious how they charge the laptop with the longer cable. I was told time and again that the shorter cable on the TB16's was because of the power delivery needs. 

I really, really, REALLY miss the e-port docking solutions. That was such a simple, elegant solution. User gets into the office, clicks in, monitors wake up, and they're done.

You have no idea how much time and energy I've put into solving this docking problem so my laptop users can have multiple monitors. The TB16 was an unmitigated disaster in our environment, with the sole benefit that it had a power button which helped wake closed laptops. I have literal stacks of dead or malfunctioning TB16 docks, a couple months out of warranty, all waiting to be e-wasted. In the meantime I've bought and tested several brands of 3rd party docks, and sadly the one that works great still has trouble on Windows 10 consistently getting 60hz on dual 4k.

Reason I mention the TB16s is that I am holding some hope that the TB19s will behave better. I already like the new TB19 form factor and the longer cable, now I just need to figure out this 60hz at dual 4k and I'll be in business. I'll know more when my DP to USB-C cable arrives later today.

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@decker12 wrote:

Thanks for the update. I have purchased the WD19TB which according to the PDF, should also be charging my 7490s. Is the "WD19TB" the same base unit as the other WD19's, but just with a different cable side-box coming out of it?

I'm still curious how they charge the laptop with the longer cable. I was told time and again that the shorter cable on the TB16's was because of the power delivery needs. 

I really, really, REALLY miss the e-port docking solutions. That was such a simple, elegant solution. User gets into the office, clicks in, monitors wake up, and they're done.

You have no idea how much time and energy I've put into solving this docking problem so my laptop users can have multiple monitors. The TB16 was an unmitigated disaster in our environment, with the sole benefit that it had a power button which helped wake closed laptops. I have literal stacks of dead or malfunctioning TB16 docks, a couple months out of warranty, all waiting to be e-wasted. In the meantime I've bought and tested several brands of 3rd party docks, and sadly the one that works great still has trouble on Windows 10 consistently getting 60hz on dual 4k.

Reason I mention the TB16s is that I am holding some hope that the TB19s will behave better. I already like the new TB19 form factor and the longer cable, now I just need to figure out this 60hz at dual 4k and I'll be in business. I'll know more when my DP to USB-C cable arrives later today.

 

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Is the "WD19TB" the same base unit as the other WD19's, but just with a different cable side-box coming out of it? - That is correct. There are a few different models available depending on the type of connection you want i.e TB or USB - C and whether you require more power i.e high end Precision, but the differences now are the cable connected, not the dock itself.

I know what you mean about the e-port docking stations, however technology changes and we have to move with it. These new docks have a much smaller footprint and dont require docking station ports to be integrated anymore. We have learned alot in the last few years with the TB16 and WD15 docks hence the redesign to take this into account. What I will say is that alot of the issues with the TB16 were driver and configuration related and once we released the install guide detailing the exact steps and what drivers needed to be installed in what order, we saw a significant drop in support requests for them.

I hope your cable works without issue, in theory it should and I expect it to. Keep me posted with your findings.

Alan

Well, good news is that the DP to USB-C cable I bought works.

Bad news is that HDMI from the monitor to HDMI on the Dock doesn't work at all when I plug that DP to USB-C cable into the WD19TB dock. It simply isn't recognized when I have the DP to USB-C cable plugged in on the 2nd monitor. Unplugging that DP to USB-C cable makes the HDMI monitor instantly light up.

What does work is if I use a HDMI to USB-C cable and plug that into the TB3 port on the back of the "side addon" piece of the WD19. Then both monitors lit up at 4k and 60hz. I will have the user dock, undock, put it to sleep, etc in an effort to make sure they always wake up at 4k and 60hz instead of reverting to some other resolution or 29hz.

So, in summary:

• Monitor 1 HDMI to Dock HDMI, Monitor 2 DP to Dock DP
  • Only DP Monitor 2 works
• Monitor 1 DP to Dock DP, Monitor 2 DP to Dock DP
  • Both monitors stuck at 4k 30hz
• Monitor 1 using HDMI to USB-C Adapter to Dock TB3 port in back, Monitor 2 using DP to USB-C Adapter to Dock USB-C "DP" port on back
  • Both monitors work 4k at 60hz

Anyway, I'll know more in a few days as the user puts the WD19 through it's paces.

Do you know if this WD19 fixes the 2.4ghz interference issue that happens from the dock's USB3 ports? That was a problem on the TB16 and it also exists on most of the 3rd party TB3 docks I've tried. 

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@decker12 wrote:

Well, good news is that the DP to USB-C cable I bought works.

Bad news is that HDMI from the monitor to HDMI on the Dock doesn't work at all when I plug that DP to USB-C cable into the WD19TB dock. It simply isn't recognized when I have the DP to USB-C cable plugged in on the 2nd monitor. Unplugging that DP to USB-C cable makes the HDMI monitor instantly light up.

What does work is if I use a HDMI to USB-C cable and plug that into the TB3 port on the back of the "side addon" piece of the WD19. Then both monitors lit up at 4k and 60hz. I will have the user dock, undock, put it to sleep, etc in an effort to make sure they always wake up at 4k and 60hz instead of reverting to some other resolution or 29hz.

So, in summary:

• Monitor 1 HDMI to Dock HDMI, Monitor 2 DP to Dock DP
  • Only DP Monitor 2 works
• Monitor 1 DP to Dock DP, Monitor 2 DP to Dock DP
  • Both monitors stuck at 4k 30hz
• Monitor 1 using HDMI to USB-C Adapter to Dock TB3 port in back, Monitor 2 using DP to USB-C Adapter to Dock USB-C "DP" port on back
  • Both monitors work 4k at 60hz

Anyway, I'll know more in a few days as the user puts the WD19 through it's paces.

Do you know if this WD19 fixes the 2.4ghz interference issue that happens from the dock's USB3 ports? That was a problem on the TB16 and it also exists on most of the 3rd party TB3 docks I've tried. 

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@decker12 thanks for the connectivity tips, that's quite handy to know that is exactly what is required to get the dual 4k display at 60hz. I'll keep that noted as the documentation isn't too clear when it advises of this.

2.4ghz interference issues - I have searched all of our articles related to the TB16 and not one of them mentions this interference. Can you provide more information on this problem please so I can investigate it further.

Alan

Here's the article on 2.4hz interference with USB3 docking stations:

https://www.intel.com/content/www/us/en/products/docs/io/universal-serial-bus/usb3-frequency-interference-paper.html

We've seen this time and again on all of our TB16s. The end result is that the typical Logitech wireless keyboard skips key, and the mouse "stutters" while you're moving it around. It's infuriating :)

The fix for the TB16s was to install a USB2 hub (AmazonBasics 3 port hub for $10 worked fine), and then plug all 2.4ghz devices into that hub. That put just enough distance between the TB16 and the wireless devices to solve the problem. It was however a huge headache at the time trying to figure out what the issue was.

Frustratingly, my user who's testing out the WD19TB for us just reported that he plugged in his 7490 via TB3 and one of his 4k monitor simply wouldn't go above 1080p. Display properties didn't have anything above 1080p as an option.

The cable he was using as a HDMI (monitor) to USB-C (plugged into the back of the dock). I had to physically unplug the HDMI cable on the back of his monitor and replug it back in for the monitor to wake back up and allow it to go to 4k.

Obviously I can't have users screwing with unplugging cables behind their monitors every day when they come into work, so we'll have to wait and see if this problem is one that goes away.

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@decker12 wrote:

Frustratingly, my user who's testing out the WD19TB for us just reported that he plugged in his 7490 via TB3 and one of his 4k monitor simply wouldn't go above 1080p. Display properties didn't have anything above 1080p as an option.

The cable he was using as a HDMI (monitor) to USB-C (plugged into the back of the dock). I had to physically unplug the HDMI cable on the back of his monitor and replug it back in for the monitor to wake back up and allow it to go to 4k.

Obviously I can't have users screwing with unplugging cables behind their monitors every day when they come into work, so we'll have to wait and see if this problem is one that goes away.

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@decker12 thanks for this additional info. I agree with you that having the end users have to do that is not how you would expect it to work. My concern is that this is a scenario or configuration that we have not encountered during testing and development and that I may need to raise it to engineering for further investigation. 

Before I can do that they will require a troubleshooting to be exhausted first before it gets escalated. I would recommend running through the troubleshooting steps for the WD19TB as per this article. It goes through the multiple different monitor configurations / connection types etc. 

https://www.dell.com/support/article/us/en/04/sln316830/how-to-use-and-troubleshoot-dell-thunderbolt-docking-station-wd19tb?lang=en

I hope this helps and I look forward to hearing how you get on.

Alan