Dell XPS 15 9550 video signal drops using USB-C to DisplayPort cable

I have the same problem with the XPS13 9350 using a usb-c to hdmi cable. External monitor turns on and off randomly which becomes more pronounced when I close the lid (sleep on close lid is OFF). Funnily enough I tried a longer HDMI cable with Ethernet and I was getting no image at all with lid closed. I also have bios and drivers updated.

I'm having the exact same issue...

i experience intermittent blank screen as well as total lost of signal through USB-C. I've tried with and USB-C to display port adapter as well as the new Dell dock (TB15 w 240W).

Very often my XPS 15 9550 goes to blank screen when the Action Center is launch the first time after the external monitor is connected. After the screen comes back, subsequent opening of the Action Center is fine.

With the same monitor ASUS PG287Q and cable, I am able to keep my 3 yo MacBook Pro connected with no issues for hours, if not days.

Dell, please help us help you.

I'm having the exact same problem.

Does anyone from Dell actually read these forums?  This post has been here for two months with only a bunch of other XPS 15 users saying "Me too!"

This appears to be a real problem.  Does anyone know how to escalate this?

I even mailed my XPS 15 to the depot explaining my issue with external video monitor support. They took over a week and just sent me back the machine without any repair. Dell service did not even contact me to diagnose the issue together. I'm so wanting to have a great laptop alternatives to Apple MacBook Pro. But, Dell is trying very hard to get rid of any dwindling high-end customers that exists.

I've wasted so much productive hours trying to get this machine to work for me since December.

All those raving reviews of XPS were coming definitely from people who had only spent 1 hr with the machine. And definitely the reviewers didn't have to work with Dell support.

Same issue here. Have the latest BIOS and all Dell updates.

Hi,

I'm getting this same issue now too and it's driving me nuts. Generally: I'm super unimpressed with the stability and quality of the drivers for what is pretty decent hardware.

Using a Google USB-C to DisplayPort adapter going to one 27" monitor, HDMI to another 27" (Benq GW2765HT). 

Intel drivers (not Dell version) v20.19.15.4444 from April 22 2016 (I think the 20 is the Dell number, but it's the Intel v15 that I installed fixing the "crashing on various graphics editor" issue)

Nvidia are the latest  v10.18.13.6519 from May 5 2016

BIOS is latest (updated last week)

Randomly, and regularly the screens will flash black and then recover. I switched the DP and HDMI between the monitors and it still occurred but worse: the DP wouldn't recover and it reverted to the laptop panel.

Oh my.. thanks for the prompt about this. I just dialled out from my phone today and as soon as I hit dial the DP display went black! I think you're onto something here

Easy fix: reduce Output Power of your WIFI, found in advanced properties of the WIFI, to 75% or 50% in some instances or swap the WIFI card for Intel card.

Same with me. All drivers up to date but usbc is the only way to get a decent external monitor working to a. DisplayPort. When I use a simple HDMI only cable, I'm getting a proper signal to an external dell monitor (34 inch) which does not turn off, but only at 50mhz which makes my eyes hurt after a while on such a large monitor. I tried 3 different usbc to DisplayPort dongles and all work, BUT for a few minutes if that, before the external screen turns blank for a few seconds and it keeps repeating itself no matter what I do. I have also noticed the problem is more pronounced if my power cable is not plugged into the laptop leading me to think it's all related to power issues of some sort when using the usbc. If indeed it's because wifi is taking all the power off this laptop or conflicting with usbc. Unfortunately if my wifi is turned to half its not strong enough to work on as I have a weak wifi signal as it is so I guess I will have to buy another wifi card and tinker with the machine. So I would like to try the solution mentioned here and elsewhere to change the wifi card (as long as it doesn't ruin the warranty) then can you kindly point a link to the compatible wifi card I can swap it too that seems to work?

I have a Dell 34 inch monitor that I cannot get to work at all with a CableCreation USB-C to Displayport adapter.  The Amazon add that I purchased it off had many reviews where this was 'plug and play' easy with the a Dell XPS 9550.  What am I missing?  Tried with and without power adapter and reducing the wifi power as stated above.

I've had the notebook a week and I'm about to send it back as I need a good docking solution.

Two days ago my dell "supportassist" software came up with message for driver updates - video, chipset and thermal with video being critical (for Intel Graphics 540). Installed those on my 9350 and now the external screen (4K @60Hz though T3-Display port Startech dongle) works rock solid... Fingers crossed, almost two days of heavy use + internet, no video signal drops...