XPS 13 9370 and external 4K monitor.

By the way, the "definitive information" you were looking for is found on Intel's site.  Since the GPU is integrated into the CPU, you want to check the CPU specs.  The website "ark.intel.com" is a great resource for that, and if you go there and select the i7-8550U processor, you'll find the following:

4K Support -- Yes, at 60 Hz
Max Resolution (DP) -- 4096x2306 at 60 Hz

And if you're curious about why the capabilities/limitations of the options I mentioned above exist, I wrote a long somewhat technical post about USB-C/Thunderbolt on this forum a while ago here if you're interested: https://www.dell.com/community/General/Demystifying-USB-C-and-Thunderbolt-i-e-adapter-and-dock/m-p/5153006

Thank you for your time.

Hi,

I've bought a XPS 9370 and i can confirm that it works 4k 60 Hrz. I'm using a plugable thunderbolt dock and it works perfectly.

I used to had a surface pro 4 and with the same monitor i had to use an adaptor with and active hdmi so it can do 60 hrz but not with this. I simply connect my LG 27UD58-B via display port to the dock and worked flawlessly.

Regards,

I am also considering buying the XPS 13 9370 and have a few questions:

1. How come you mention the laptop can only have dual 4K displays at 60Hz. Based on what I read, this laptop has 2 thunderbolt 3.0 ports and noticed online that each thunderbolt 3 port can carry dual 4K displays so shouldnt this laptop actually support 4 (4K) displays?

2. Thunderbolt 3.0 is apparently capable of daisy chaining 6-7 devices, so If I use 1 thunderbolt 3 port and connect it to a 4K monitor with dual thunderbolt 3.0 ports (one for it and one for out), shouldnt I in theory be able to connect via daisy chain in thunderbolt up to 5-6 more 4k monitors?

3. What are these dual 4K monitor limitations related to? the TB 3 port, the graphics card, the Intel processor? What's the max amount of 4K displays that the Intel internal GPU of the laptop will allow? Because as I mentioned in my 2nd question, given that each TB3 port is capable of dual 4K and the laptop has 2 such ports, shouldnt the laptop be able to carry four 4K monitors? Or is it a Intel GPU limitation that can be overcome with an eGPU? 

4. I want to be able to connect six 4K display monitors to this laptop. Is there any way I can do this? Like maybe use one TB3 connector to a 4K display monitor then daisy chain it to a further 2 more 4K monitors? And then repeat same step for the 2nd TB3 connector on the laptop? So I would have 2 directly connected 4K displays to each TB3 port and then the other 4 daisy chained to the 2 already connected?

There's a video video on YouTube called "Six 4K Screens On A Mac Pro - 50,000,000 Pixels!" showing someone who connected six 4K displays to a macbook via an eGPU. If i buy an eGPU like top of the range NVidia and connect it to the laptop's TB3 port, would I then have 6 TB3 ports on that eGPU which will then allow me to connect to six 4K monitors?

5. Is the 3rd port on the laptop (the USB C non TB3 port) capable of having 1 4K monitor or 2 4K monitors? or none? 

6. Given the 3 ports available, what's max number of 1080p monitors I can connect? What about max number of Quad HD monitors? 

7. Are there any Dell monitors out there capable of daisy chain via thunderbolt 3.0 as opposed to simply daisy chain via display port? I saw LG came up this year with a 5k display capable of daisy chain via TB 3. Any major differences between being able to daisy chain via display port vs. TB 3 connection? Looks like a lot of monitors can be chained via display port but none can be chained via TB3. How come?

1. Each Thunderbolt 3 output can support dual 4K displays, but that doesn't necessarily mean that both of them can do that simultaneously.  It's possible that there are only 2x DisplayPort outputs wired from the GPU to the Thunderbolt controller that feeds both of those ports.  But even if each Thunderbolt output has 2x DisplayPort outputs wired to it separately, the Intel GPU is limited to 3 total independent displays regardless of resolution or how they're connected, counting your built-in panel.  If you chose not to use the built-in panel, then you may be able to run 3x external 4K displays simultaneously, but I don't know this for certain because I believe this is one of the first (or maybe THE first) Dell laptop with more than one Thunderbolt 3 output.

2. Thunderbolt is indeed capable of daisy chaining, but there's still a bandwidth maximum.  Thunderbolt 3 can carry up to 40 Gbps in each direction.  A 4K display running at 60 Hz consumes about 16 Gbps -- so no, you couldn't daisy chain 6-7 4K displays off a output, even if the GPU allowed an unlimited number of displays, which it doesn't.

3. I've already basically answered your Question #3 above.  There are GPU limitations around total number of displays and maximum resolution on a given display, then there are bandwidth limitations on specific outputs and how they're being used -- for example, regular USB-C (not Thunderbolt) when used solely for display traffic can handle 4K at 60 Hz, but when used through a device that wants to allow USB data at the same time, display bandwidth is cut in half.  Your intended display configuration must always fall within all of the limits of the various hardware in play.

4. The only way to get around the limitations I've already described would be to use DisplayLink adapters, since those don't tap into GPU outputs and instead act as "indirect/virtual" displays.  However, displays attached via DisplayLink have some significant functional drawbacks compared to displays connected to native GPU outputs, especially if you were planning to run multiple 4K displays that way.  Fyi, running 6x 4K displays all driven by GPUs would be considered a fairly extreme configuration even by workstation-class desktop standards right now, so I'm not sure why you're expecting to achieve that on a laptop that's designed to be an ultraportable as opposed to a workstation-class system, but I don't even know of any workstation-class laptops that would handle your intended configuration, again ignoring the DisplayLink option.  If you buy an eGPU, then if you attached your displays to the eGPU's own outputs, you'd be able to use whatever display configuration was supported by the GPU you're using.  An eGPU would not change the limitations that apply to displays directly connected to the XPS 13 though.  Also, eGPUs don't have TB3 ports.  They typically have DisplayPort and HDMI outputs, so I'm not sure how you expect to get 6 TB3 ports by getting an eGPU....

5. The USB-C port can do a 4K display at 60 Hz when used solely for USB-C, but it will only do 4K at 30 Hz (or 2560x1600 at 60 Hz) when also being used to carry USB data.  I wrote an extensive post about USB-C and Thunderbolt 3 capabilities here if you're interested.

6. A single Thunderbolt 3 port fed by dual DisplayPort 1.2 outputs (which is how the XPS 13 is set up) has enough bandwidth for 8x 1080p displays or 4x QHD displays -- but again, your GPU only allows 3 displays anyway.

7. The reason Thunderbolt displays don't offer Thunderbolt daisy-chaining is because the displays that use Thunderbolt are using it because they require basically all of the display bandwidth available over that Thunderbolt connection just for that display, so there wouldn't be much bandwidth left to pass along to a daisy-chained display.  That's also why you can find DisplayPort daisy-chaining on 1080p and even QHD displays, but typically not on 4K displays -- again, a 4K display uses all available DisplayPort 1.2 bandwidth.  DisplayPort 1.3 offers more bandwidth and DisplayPort 1.4 additionally supports display data compression, so at that point it will make sense for even 4K displays to offer daisy-chaining, but PCs/GPUs that support DisplayPort 1.3 and 1.4 are still relatively rare, so I think daisy-chaining is still being omitted from those displays to avoid customer confusion.

@Rickye in addition to my answers above, I thought I'd expand a bit on the eGPU option because your question got me thinking about possibilities.  First, I don't know of a single GPU that can handle 6x 4K displays, but if one exists, it would probably be a much more expensive Quadro/FirePro card, not a GeForce/Radeon card.  And even if you found a card that supported 6 displays and offered 3x DisplayPort 1.4 outputs, which would provide enough bandwidth for 6x 4K displays, your next problem would be that you'd need to find displays that actually supported DisplayPort 1.3 or better (and offered daisy-chaining), because if the displays only supported DisplayPort 1.2, then the GPU would only transmit DisplayPort 1.2, which would mean you wouldn't have enough bandwidth anymore.  If you could find a GPU that offered 6 separate DisplayPort outputs, then you'd probably be good to go, but I don't know of a GPU that does.  Chances are that the only reasonable way to connect 6x 4K displays all driven by a GPU rather than using DisplayLink would be to get a desktop PC that had at least two GPUs installed.

Another option I considered was finding an eGPU that supported 4x 4K displays (since that's probably easier) and then connecting an additional 2x 4K displays via the XPS 13's other TB3 port in order to get your desired 6x, but I don't think that will work well either.  Although TB3 can handle 40 Gbps of bandwidth, I don't know whether the XPS 13 9370's setup means that each TB3 port can do 40 Gbps simultaneously or if it's "40 Gbps per port but only 40 Gbps max total across both ports at any given time" because of a possible limitation on the Thunderbolt 3 controller that manages both ports.  If it's the former, that would probably work, but if it's the latter, then the display setup I suggested would not work, at least not very well.  Dual 4K displays connected over TB3 would consume ~32 Gbps of bandwidth, and an eGPU would attempt to connect with the XPS over a x4 PCIe 3.0 connection, which can also consume up to 32 Gbps -- that obviously puts you way over the 40 Gbps limit.  Display traffic always gets priority over PCIe traffic on TB3, so if you had 2x 4K displays connected directly to the XPS, your eGPU bandwidth would get severely throttled.  Even if you moved one of those 4K displays over to the USB-C connector in order to take its bandwidth consumption off the TB3 controller, you'd still be throttling your eGPU somewhat, and you'd also then be using all available ports on your system without having figured out how to charge it yet, which means somewhere in this setup you'd need to have something that powers the system.  Some eGPU enclosures can do that, and some displays can do that, or I guess you could buy a Thunderbolt dock to provide power and connecting one of your 4K displays to that, but that's now even more cost and complexity.

As you've probably figured out, there aren't really any good options here, at least not any that are guaranteed to work -- and that shouldn't really come as a surprise since again, you're trying to set up a display configuration that's extreme even by workstation desktop standards on an ultrabook laptop that simply wasn't designed for that type of use case.

thanks for you detailed answers. Here's the video of the person who connect 6 4k Monitors to his laptop via eGPU:

https://www.youtube.com/watch?v=5Y3C5Mthmlc

So I guess this should also work on Dell?

Also few more questions:

1. Is the bootloader for this laptop Legacy BIOS or UEFI?

2. Is the SSD hard drive using GPT or MBR partition?

Sorry for three posts in a row here, but I did a bit more digging on that video, and apparently he has 3x 4K displays connected directly to the Mac Pro and 3x connected to the eGPU.  Yes, that should work on the 9370, but if your eGPU "only" supports 3x 4K displays and you have to connect the other 3x displays to the 9370, there's only one real option:

- Run 2x 4K displays from one of the Thunderbolt ports on the left side of the XPS using either a dock like the TB16 or a Thunderbolt 3 to Dual DisplayPort adapter.  I would recommend the dock option because it would provide power to the system and allow you to connect other USB devices to the system, which will be important because you won't have any other ports available for this purpose in this setup, as you'll find out.

- Connect the third 4K display to the USB-C port using a USB-C to DisplayPort cable or dongle.

- Connect the eGPU to the other Thunderbolt port on the left, and connect your other 3x 4K displays to the eGPU's own outputs.

The main concern with this setup is bandwidth.  Again, I don't know if each of the Thunderbolt 3 ports can handle 40 Gbps simultaneously or if it's 40 Gbps total bandwidth across both Thunderbolt ports.  If it's the former, you will be fine.  If it's the latter, the performance of your eGPU and therefore the displays attached to it will suffer significantly.  A typical desktop-grade GPU supports PCIe 3.0 x16, which is 128 Gbps of bandwidth -- but Thunderbolt 3 "only" offers either PCIe 3.0 x4 or x2.  The 9370 supports x4, which is 32 Gbps.  However, your 2x 4K displays on the other Thunderbolt connector will already be consuming 32 Gbps of bandwidth for their DisplayPort traffic, and since Thunderbolt always prioritizes DisplayPort over PCIe, if the XPS 13 9370 only offers 40 Gbps total bandwidth across its two Thunderbolt ports, then your eGPU will only have 8 Gbps of bandwidth left, equivalent to a PCIe 3.0 x1 connection.  Unfortunately I don't know for sure how the bandwidth max works on the 9370, and I doubt the average Dell sales rep can be considered a reliable source for this.  The ideal scenario would be to test it, but you'll probably have a hard time finding an XPS 13 9370 owner with the necessary hardware to test whether pushing more than 40 Gbps of total bandwidth across its two Thunderbolt ports is possible.

@Rickyeas I said, if you use an eGPU then as long as you connect the displays directly to the eGPU's outputs, the eGPU's capabilities and limitations will be what's important.  So yes, it should work, but I can't speak from experience because I haven't personally worked with eGPUs or any other situation that involved 6x 4K displays.  And I jumped around in the video a bit, but I didn't see him explain how exactly he connected 6x 4K displays to a 7970 card.  I didn't see 6x DP outputs or hear him mention daisy-chaining.

Sorry, forgot to answer the other questions.  The system will come set up to boot in UEFI mode.  It may support being put into Legacy BIOS mode, but I've noticed on some newer systems like the Latitude 7490, they only support Legacy boot for USB devices now, whereas anything booting from the internal hard drive must use UEFI.  I don't know if the 9370 works that way, but there's no real point to using Legacy mode on this system anyway, since any OS it supports will also support being booted in UEFI mode.

Hard drive partition layout depends on the boot type you use.  Operating systems configured for UEFI mode booting need a hard drive set up as GPT.  Operating systems configured for Legacy BIOS mode need a hard drive set up as MBR.  The XPS 13 9370 will arrive from the factory configured for UEFI booting and with the hard drive in GPT mode.

You cannot use DisplayPort daisy chaining / MST at 2160p60 because one monitor consumes almost all of the bandwidth, unless you have the GPU, monitor and MST hub (if applicable) supporting the recent DP1.4 spec.

Adding screens with eGPU is dependent on which GPU, as @jphughan said. But it should not be limited to six. Theoretically you could use a PLX bridge to add many GPUs to each external PCIe slot, and daisy chain six Thunderbolt PCIe enclosures on each Thunderbolt port. So if you are driving UHD60 displays with no intention of gaming, the sky is the limit.

If you want to add displays with an external graphics card without any serious gaming performance, the smallest is "eGFX Breakaway Puck Portable eGPU System" with 3x DP and 1x HDMI, but only 45W of power delivery (just enough for the Dell 9370, but not future proof like the Gigabyte Aorus with 100W).

I have the Aorus Gaming Box with AMD R9 Nano installed, and that gives 3x DP and 1x HDMI 2.0 for 4x 2160p60 displays. For people wanting to know more, head to egpu.io forums and there are already people posting about how well the Dell XPS 9370 fares with external graphics and giving lots of information on performance and quirks.

As for the people wanting more monitors at lower resolutions from the Intel GPU, you can get DisplayPort MST hubs - 4x1080p 60Hz uses the same bandwidth as 1x 2160p 60Hz display. I assume it breaks the three-display limit because the displays are connecting through the MST hub as one stream - hence many monitors can share one of the three DisplayPort outputs of the Intel GPU. Somebody correct me if I am wrong.

i just wanted to ask u a question can i output 4k 60hz from the dell xps 13 to 4k monitor using only a USB type c cable ? excuse my ignorance ... thank  so much 

To do it with a regular USB-C cable, you'd need a display that had a USB-C input and you'd need to make sure your USB-C cable supported USB 3.1 Gen 1 or better, or just make sure the cable you buy specifically mentions that it supports video output or (the formal name) DisplayPort Alt Mode.  Some USB-C cables only support USB 2.0 because they're only intended to be used for device charging and basic data transfer.  I wrote a long post about USB-C and Thunderbolt cables here if you're curious.

Thanks for all your input to this thread. I have a 9370 and am thinking if buying the LG 27UK850  monitor, partly because it has a USB-C input for video and audio, which means I don't need to buy converter cables or adapters and can connect it direct to the XPS 13. From what you have said, that should not be a problem. Am I right?

 It comes with a USB-C cable so I assume that should comply with the requirements you mention.