XPS 13 9300 thunderbolt 3 issue

@davdatong 

Hey thanks for your information. I think we have the same issue. Using your information, I tried turning on my 9300 with the cable already plugged in and it works. So far 2 out of 2 times.

I tried removing the cable and plugging it back in while powered on, and it starts disconnecting/reconnecting again.

I also tried a "restart" instead of a shutdown, and it starts disconnecting/reconnecting.

Like you, my 9350 works fine, and I've also updated all my drivers. The only difference is that we use different monitors and hubs.

@describee 

I am using the Dell 49" U4919DW monitor.

The dock is this one https://www.dodocool.com/p-dc47b.html

It says it's Thunderbolt compatible and it's already worked with my older 9350, so why can't it work with the 9300?

@describee I am using a Samsung CF791 Series widescreen monitor.

Nope. Didn't resolve my issue with the power cable plugged in and I've tried both 85W and 15W although I don't think it will work with 15W.

@Philskies .. Yes. I've got exactly the same issue as you with all BIOS updated.

I've raised a ticket with Dell and they mentioned that there will a new BIOS available which resolves display issues with thunderbolt. However, the release date for this is in May!

It will be great to raise a ticket with Dell if you haven't already as we maybe able to escalate  this with more tickets raised.

@davdatongNow I am confused, because the CF791 doesn't have any Thunderbolt 3 ports?

@Philskies The dock that you are using is a USB-C hub. It's just that all Thunderbolt 3 ports are also compatible with USB-C devices.

In addition, your dock appears to be using the older HDMI 1.4 spec, which will support your monitor only at 5120x1440@30Hz (instead of 60Hz). You shouldn't even be using that dock to get the most out of your monitor. You should get a dock that supports HDMI 2.0 (which can output 4k@60Hz at the very least)

The U4919DW also supports connecting directly to your laptop via a USB-C data cable (e.g. using one of these https://www.amazon.com/Cable-QCEs-3-1-Thunderbolt-Compatible/dp/B07T19KQYF/ref=sr_1_4?dchild=1&keywords=usb-c%2Bdata%2Bcable&qid=1586306155&refresh=1&sr=8-4&th=1). Have you explored this option?

In any case, the fact that a Dell monitor has the same issue as a Samsung and LG monitor gives me some hope that Dell will be able to resolve this issue since I would expect a Dell-branded monitor to work just fine with a Dell-branded laptop!

With that being said, I haven't had any issues myself connecting a 4K60Hz display or a QHD144Hz to my laptop so far using various USB-C or TB3 to HDMI adapters so far. It is starting to look like there is some bug in the graphics driver with ultrawide screen monitors at the moment, given that the issue manifests itself on both TB3 and HDMI-via-USB-C-alt-mode monitors.

@describee. Yes, mine has a thunderbolt connection. Exact model: C34J791 and purchased in UK Currys.

https://www.currys.co.uk/gbuk/computing/pc-monitors/pc-monitors/samsung-c34j791-quad-hd-34-curved-led-monitor-white-silver-10181380-pdt.html?intcmpid=display~RR

Hey @describee , thanks for your advice, especially on my dock's lack of HDMI 2.0. No wonder my cursor is so choppy on my external monitor. I always thought it was just because of a weak video card.

I guess I can try connecting direct via USB-C data cable. I'll let you guys know the results when I try it.

Edit: I just did as you suggested and now I have the 9300 connected directly to the Dell monitor and runs way smoother. I'm using the other TB3 port for my low-end dock. This should suffice for now until I upgrade to a newer better TB3 dock with all the I/O I need. Do you have any suggestions for TB3 dock brands or models? I need an ethernet port, a Thunderbolt connection to my monitor, a few USB2.0/3.0 ports, and maybe sound. Nothing super fancy.

@Philskies Just wondering if Power Delivery etc. works fine on the U4919DW connected directly to the laptop and you can essentially power up the laptop using the monitor with no issues?

You might want to have a look at Amazon reviews to see what Thunderbolt 3/ USB-C dock suits your needs and has fewest problems. So far from what I see, a lot have mixed reviews out there. Many of the docks out there have limitations (e.g. 4K only at 30Hz or only USB 2.0 ports when video is connected), etc. I think Dell has a TB16 dock which generally works fine. The best option I feel is to use one TB3 port for video and the other TB3 port to handle USB, Ethernet etc. connections.

"I've raised a ticket with Dell and they mentioned that there will a new BIOS available which resolves display issues with thunderbolt. However, the release date for this is in May!" @davdatong 

Has anyone heard any updates on this? I'm having issues with this as well.

@saswett ... I have spoken to Dell these last couple of weeks and unfortunately they now mention the new update won't fix this issue and they have no plans to get this fixed as they think I should be using an external dock to get this working! I was shocked when they told me this during the support call.

I am now contemplating whether to return my laptop and get a full refund.

It will be good if you can also raise a ticket with Dell so they are aware that many people are having this problem.

@davdatong Thanks for the update. I specifically got a new monitor with Thunderbolt 3 support (LG 32UL950) so I wouldn't have to get an external dock and could minimize clutter and extra boxes. My work laptop (HP Elitebook) works just fine with my new monitor and one TB3 cable to do everything.

This is nonsense that they will not do a simple software patch in order to make people buy their $300 docking station.

I really want to live the one cable dream!

@saswett Just to check, have you tried the following:

- Charge up the laptop with another USB-C cable, then plug in the TB3 monitor. Does this work?

- Does the TB3 monitor connect if say, you use the DisplayPort output instead and connect it to an adapter to USB-C?

- You have tried to enable TB3 boot support etc, I assume?

- Is the display detected at all? Does the system go into a connect/ disconnect loop or nothing at all?

@saswett . Yes, I understand your frustration, I also want one cable to do everything I need... I don't see how it works in an older version of their dell xps and doesn't for this. It seems like a build flaw in the new Dell XPS and maybe unable to fix with a software update...

@Philskies You are having the issue even when the USB-C plugged directly in to the laptop? If so, please contact Dell -- you have a Dell monitor and a Dell laptop -- chances are, they would be more willing to fix this.