Precision 5510, U2719DC, USB-C not working

@Mikecotter86  this is a known issue, albeit not a well communicated one.  Bear with me here.  Basically, several users reported that the XPS 13 9350 would not send a video signal when connected via USB-C to Dell USB-C displays.  This occurred even though the XPS 13 9350 worked fine over USB-C with other displays, and the Dell USB-C displays worked fine over USB-C with other sources, and the XPS 13 9350 worked fine using a USB-C to DisplayPort cable to Dell USB-C displays.  The number of people reporting this issue ultimately led to this KB article.  As you'll see if you read the article, unfortunately Dell not only basically said, "We're not going to fix this because we consider that system end-of-life" -- even though this is a case of a Dell system not working with a Dell display -- but they also didn't even share the underlying cause for why this configuration doesn't work even though it obviously should.  After that KB was published, it was reported by multiple people that this exact issue also occurred on the same-generation XPS 15 9550 system.  The Precision 5510 you have is the sister system of the XPS 15 9550; the only real difference is that the Precision version uses a Quadro GPU whereas the XPS 15 uses a GeForce GPU, but since the Intel GPU has direct control of all video outputs anyway (the NVIDIA GPU only works as a render-only device through NVIDIA Optimus), that distinction is unlikely to matter.

The only real workarounds would be to use a USB-C to DisplayPort cable or add a docking station between the system and display.  I'd actually recommend doing one of those anyway because the Precision 5510 is designed for a 130W power source, and Dell USB-C displays don't supply that much (some but not all Dell docks do), so if you rely on a USB-C connection to that display as your power source, the system will be operating on a reduced power budget, and it will respond with behavior such as slower battery charging and possibly reduced CPU and GPU performance.  You can work around this by keeping the system's AC adapter directly connected as well, but at that point you're connecting two cables anyway, so you may as well use a USB-C to DisplayPort cable.  Unless you really wanted to carry USB data traffic over that USB-C connection in order to plug USB peripherals into the display?

@jphughan ,

Thanks for the reply a while back. 

It sounds like a USB to display port adapter is the way to go for this outdated (4 year old) precision. LoL

I just want to make note and add one thing. The USB C video feed works just fine with one of those AOC 15" portable external laptop screens. I've had no problem with using the USB C video output for that screen. Any idea why? Does that support your earlier reply?

https://us.aoc.com/en/monitors/i1601fwux 

Thanks again,

I am having this exact issue with connecting a Dell Precicion 5510 with a new Dell U2720Q monitor, over USB-C to USB-C.  I explicitly asked about this configuration when I purchased this monitor and was told it will work.  I've resorted to connecting via USB-C to DP.

One note here, is that with 4K screens, the HDMI 1.2 of the Precision 5510 only supports 4K @ 30 Hz, and this 30 Hz results in a really bad/laggy experience. This is the reason to go to USB-C to DP for the 4K @ 60 Hz support.

Also, yes, it would have been *really* nice to have a single USB-C to USB-C connection btwn 5510 and U2710Q, for both video and USB data, and supplement the power with the original 5510 130W power brick (as the U2720Q only supports 90W charging to laptop over the USB-C); this would be two cables to laptop (130W power and USB-C), but you'd now have a USB hub with the connected U2720Q, which is the config I was going after (makes for a much cleaner desk layout, if my periph's are connected to the display, instead of the laptop).

I still want to know why the heck the USB-C to USB-C doesn't work with a Dell U2720Q (or other Dell monitors), I mean, they are both Dells.  What a screw up. 

Anyway, this article gave me the info I needed to at least get the Display to render. Thanks for that!

tags: precision, 5510, usb-c, u2720q

Gents, my problem is that the USB ports on the monitor are not working. the connection between precision and the monitor is via USB-c- USB-c cable. 

is there anybody to see a similar issue? and how has it been solved? 

Hi,

This is incredible.
I just bought a Dell U2720Q to connect it via USB-C to my Dell Precision 5510. I specifically asked Dell support if this was possible . Ok main reasons were power charge via USB-C, but nobody mentioned, that the combination would be impossible!
I am highly irritated and frustrated.
It was the exact plan to use the monitor with usb attached periferals (keyboard , mouse, printer) with a PC and separately with the Dell 5510.
Are you dead serious that there is no decent solution?
Kind regards
Fritz P.

@fripr  There is a workaround, and if it's any consolation, a single cable setup in your case wasn't going to be a great experience anyway, because even if it weren't for this weird interoperability issue, if you connect to a 4K 60 Hz display purely from a USB-C cable from that system, you have two downsides:

• Because that system only supports DisplayPort 1.2/HBR2 over USB-C, if you connect to a 4K 60 Hz display via USB-C, you either need to sacrifice refresh rate or USB speeds.  Specifically, you can either run 4K 60 Hz and only have USB 2.0 data speeds available, or run only 4K 30 Hz (or 1440p 60 Hz) and get USB 3.x speeds.  This has to do with how USB-C works and the bandwidth limitations of DP 1.2/HBR2.
• The Precision 5510 is designed for a 130W power source, which is more power than the U2720Q can provide.  So if you rely on the display as your power source, the system will attempt to adapt to the reduced power budget by doing things like reducing its battery charging speed and even its performance, especially if you're doing anything that uses the NVIDIA GPU.

So in terms of the workaround, it will involve multiple cables, but it will also give you more functionality.  Here's what you can do:

• Get a USB-C to DisplayPort cable to handle video.  You'll be able to run 4K 60 Hz that way.
• Get a USB-C to USB-A cable that supports at least USB 3.x Gen 1 (5 Gbps).  You don't need Gen 2 (10 Gbps) support since the display doesn't support it, but some C to A cables only support USB 2.0, so avoid those.  Connect the USB-C side to the display and the USB-A side to your Precision.  Now you'll have USB 3.x Gen 1 running between your system and display.
• Continue powering your system from its own 130W power adapter for optimum performance.

If you don't want all those cables, then the only way to have that system run 4K 60 Hz, USB 3.x, and enough power to run your system properly all over a single cable is to use a Thunderbolt 3 dock, like the Dell WD19TB.  That would actually allow you to run dual 4K 60 Hz.

I have a fairly current Latitude 2in1 and just bought a U2421HC monitor and guess what... My USB-C to USB-C also gives me the message that no signal is transferring through - any ideas on that too? Or suggestions for 1-2m USB-C to C cables that will actually do the job?

@JeanbonP  What exact Latitude model do you have?  Are you using the USB-C cable that came with the display?  Have you tested your system and cable with another display, or another system and the same cable with your existing display?

Hi it's a Latitude 3390 (P69G001) - the supplied USB-C to C cables does work but it's too short for my needs, and the replacement CtoC cable isn't transferring any signalb to the monitor. Any longer USB-C to C cables you can suggest please - carrying signal and charge? 1m should probably do (as opposed to the short cable supplied with the monitor). Thanks.

@JeanbonP  Not all USB-C cables have the same capabilities.  Here is a 6 ft. / 2 meter cable that supports up to 4K 60 Hz video, USB 3.1 Gen 1 (5 Gbps), and USB PD up to 100W.  If you need USB 3.1 Gen 2 (10 Gbps), then passive cables right now seem to be limited to 3 ft. / 1 meter, except for this active cable which is 10 ft. / 3 meters -- but its USB PD capability is limited to 60W rather than 100W.

@JeanbonP  Just to add a quick note to my reply above, you didn't specify what display you're using, but I'd be surprised if it came with a cable shorter than 3 ft. / 1 meter.  Even 14-15" portable USB-C displays I've purchased that are designed to be used right next to a laptop come with cables that long.  The next size down would be 18 inches / 0.5 meters, but if you're using a desktop display, I can't imagine it would come with a cable that short.  A 6 ft. / 2 meter cable is pretty typical for desktop-type cabling, so I'd go with that if at all possible.  But if your display actually supports USB 3.1 Gen 2 and you want to use it (although I'm not sure your system does, come to think of it), then at least based on the cables I know about in the market, it seems you'll have to choose between short length or 60W power max.

Thank you for your very helpful advice on this issue. I have gone down the path of a USB-C to DisplayPort option via a Dell adaptor because I discovered that HDMI only gives me 30Hz on my new monitor rather than the 60Hz. (This is a work around until my new Dell docking station order is fulfilled - a Dell WD19TBS.)

However in using the USB-C to DisplayPort option, I discovered that all the USB ports on my display stopped functioning (as you pointed out). You mention attaching a separate USB cable (I presume A to A) from my display to my system. Does that mean if I connect my display to my laptop by a male to male USB A cable, that my remaining (2) display USB ports will now function?

(For reference I have the Dell U2720Q monitor and a Dell Latitude 73790.) Cheers, Murray