XPS 13 9300, BIOS 1.0.10, USB Type-C to DP adapters no longer work

@Kyle Sh. Dell reached out to me via Twitter this morning to ask me try BIOS 1.1.0.  Still does not work with my 3rd party adapter.  Waiting on them to respond. The person I've been communicating with thru Twitter stated they are a L3 engineer and their primary role in REC is investigating this issue.

Dell released a new bios this morning, v. 1.1.0.

I was under the impression that this issue was being worked on and fixed for the next bios update, but most display adapters do not work or only SOMETIMES work. It's disappointing to see this issue not fixed, especially as so many of us are working at home with docking stations.

@DELL-Cares can you please advise us on what to do? Are level 3 techs looking into this? It seems like a hugely basic flaw for a laptop to have...

@LiquidIce012 are you able to be in contact again with the L3 techs you mentioned earlier?

Well I got an answer back from the escalation path I was pursuing, and it didn't make sense.  They were talking about only being able to output 30 Hz on both new and older BIOS versions and therefore suggesting limitations on the adapters.  I replied asking whether anybody involved in that testing had actually read even the problem summary I sent them, never mind this thread, which makes it clear that the problem is adapters that stopped working completely after a BIOS update, not adapters that have reduced performance.  Still hoping to get an answer back on that.

As for BIOS 1.1.0, there's nothing in the release notes here about fixes for this.  Of course published release notes don't always include all fixes/changes, but given that one of the fixes mentioned was a security issue, it's possible that Dell fast-tracked a release to fix that problem and therefore other fixes planned for the "next release" got pushed.  But I don't have a way to know that for sure; that is purely a guess on my part.

Ok, better update from my internal escalation path:

BIOS 1.0.10 included a new PD firmware meant to fix other issues.  That firmware added a timing delay before the Alt Mode discovery process (e.g. for DP Alt Mode).  That delay is causing some dongles to generate some extra messages that are unexpected by the system at the time they are generated, which causes the system to abort the negotiation and thus not enter into DP Alt Mode.

Originally the BIOS team had planned to roll back the PD firmware as part of the 1.1.0 update, but now that they believe they understand root cause (above), they scrapped that plan and are currently working with Texas Instruments on corrective actions.

Hello everybody,

I have installed the current BIOS for the Dell XPS 13 9300 and can not make any improvement in terms of USB-C to HDMI or DP.
All tested Ugren USB-C to HDMI do not work.
I also found that the firmware in Windows Device Manager does not yet have the correct driver due to the update. A manual search for the Windows update catalog was not successful.

My USB-C to DP from UNi continues to work without problems.

@ 60Hz
@ 144Hz
@ 240Hz

I hope that Dell sharpens here in the interest of the customer and that we are all happy again.
I can only say everyone opens a ticket and escalates the topic.
I also found that only the BIOS changes but no changes are made to the firmware of the EC and PD ports.

See the Screenshots

Beste _Shade_Only Bios Version ChangedNothing ChangeUNi USB-C TO DP @ 144HzFirmware on Windows Side

I thought I was lucky.

On 1.0.11 and all previous versions I was able to get my Anker USB-C->HDMI adapter to output 4k/60hz relatively easily.  There were some hiccups here and there, but tweaking Ubuntu's display settings usually sorted them out and got me the correct resolution.

I just upgraded BIOS to 1.1.0 this morning and now that's broken.  My OS sees the display but the highest resolution it offers me is a bizarro 1280x800.

@jphughan @Kyle Sh. 

My contact also responded that the PD firmware needs to be updated

@_Shade_  which device specifically shows it does not have the correct driver? Maybe this is something we can dig into more... I've noticed drivers are often missing from the dell profile for whichever laptop/service tag you are looking at. Maybe something else exists that we don't know about yet.

Also experiencing issues with USB-C docks on my 9300

1.1.0 seemed to help at first but seeing issues again after just a few minutes.

Using a plugable UD-ULTC4K with latest drivers, fully updated windows and BIOS.

Thank you former posters for doing the work of communicating with Dell. I'm glad to see they're working on a fix for the Power Delivery and USB-C subsystems - just wanted to throw my hat in the ring as another affected customer.

I need to correct myself from earlier - the new bios DOES improve this. Certain docks that did absolutely not work previously now work sometimes. It takes a lot of unplugging/replugging and trying again.... but it works sometimes!! For some reason, I have better luck with the port on the right side of the laptop compared to the left side...

Behavior is the same for me, but instability (both or one monitor dropping) starts up quickly even in instances where I can get the docks to connect on 1.1.0 - as though different devices are being selectively suspended (USB selective suspend not in power options so cant turn this off to test).

Just bumping this thread in hopes of a resolution from Dell. My 9300 is useless for it's primary purpose (work laptop) and I'm working off a 4 year old Lenovo until it can be fixed...

Overall the 9300 has been a mess, dynamic brightness that turns on every boot despite being disabled, battery life issues, audio effects (waves nx) getting turned on after disabling, and now it does not even work with my dock or my usb-c HDMI adapter. A portable with unreliable battery that also can't dock fails it's two primary use cases...

@BlipBloop  and others, just got an update from my internal contact. BIOS 1.2.0 is planned to include fixes for 3rd party display adapters and is currently expected to be released on September 4. That’s all the information I have, so please don’t ask which adapters will get fixed or why the update isn’t expected to arrive sooner. I’m passing along what I receive.

Well, I rolled the dice and bought another XPS 13 9300 after returning my original one. First thing I did was install all the latest drivers and BIOS updates, but I'm still only getting 4k @ 30Hz while hooked up to my CalDigit TS3+ Thunderbolt 3 dock. Looks like I'll be returning this machine for a refund, too.

You would think that Dell would test their product with the most popular Thunderbolt 3 dock on Amazon...

Link to CalDigit TS3+ here: https://amzn.to/39Ltz1L