Dell Vostro 15 3510 stopped WFHD (21:9) external monitor support

There isn't one;  the HDMI port on this system supports only FHD resolution, max.

https://www.dell.com/support/manuals/en-us/vostro-15-3510-laptop/vostro-15-3510-setup-specs/external-ports?guid=guid-4c4cc1ba-66a4-45f0-8dfc-6013a624ddc0&lang=en-us

The Dell Vostro 15 3510 might have stopped supporting the WFHD (21:9) external monitor due to outdated graphics drivers, compatibility issues, faulty cable connections, incorrect monitor settings, laptop display settings, operating system updates, hardware limitations, graphics card performance, monitor firmware, or hardware malfunction. To resolve the issue, update graphics drivers, check compatibility, ensure correct cable connections, adjust monitor and laptop settings, update the operating system, verify hardware capabilities, consider graphics card limitations, update monitor firmware, or test the monitor on another device. If troubleshooting fails, contacting Dell support or a technician could help.

@user_306c1a​ 
I updated every conceivable driver and applied all the widows updates, nothing worked.
I even tried removing the updates after which this stopped working, without any result.

In my opinion this should still be able to work. 
Oh, and the monitor works correctly on this resolution on other laptops I posses, without any changes and with the same windows updates applied.

I have the exact same problem, have had this Vostro 15 3510 since about March 2023.

This Monday I received Windows updates as well as a bios update and a graphics driver update, since then I lost my 2560x1080 resolution.

Everywhere I go I see people saying this device's HDMI port doesn't support that resolution but I've been working for more than half a year in that resolution which is now not available anymore.

This device went from a great one to a crap one because of that.

With the graphics driver update now only crappy Intel Command Center can be used in which you can't even create custom resolutions anymore, you have to download the beta for it but even that doesn't work.

Custom Resolution Utility tool clearly shows my screen can do 2560x1080, the Intel Command center clearly shows my laptop can do that resolution also, but Windows refuses to give that option anymore, see screenshot attached.

This all because of recent updates either by Dell or Intel.

I even tried connecting a docking station, a Kensington SD3600, which I connected to one of the two 3.2 Gen 1 ports on the left side of the laptop and this docking can normally do 2560x1080 @ 60Hz easily and guess what, not even that works anymore on this laptop, it still only gives me 1920x1080 as max resolution.

When I connect another laptop to this screen everything instantly works as normal.

One of those updates completely destroyed the graphic capabilities of this Vostro 15 3510, sad to see because they will not be solving this at all, and when it doesn't even work via a docking station anymore... you're left with a  fast but useless device.

Sad sad story.

@Psylocke-X​ 

PS. : I've tried reinstalling Windows 10 & 11, tried older graphics drivers, literally tried everything, nothing works.

@Tatolino​ 

Finally a decent reply, amazing!

Going to test and see if that fixes it, will report back!

Thank you so much already for your reply!!!!

@Tatolino​ 

IT WORKED !!!!!!!!!!!!! THANK YOU A MILLION TIMES!!!!!!!!!!!!!!!!!!

You have no idea how sad I was when I lost my resolution, I use this device to do my day to day work on and this issue hampered my work performance enormously.

Also goes to show that, unlike everyone is saying all the time and even Dell is saying in the official Dell documentation, the HDMI port is NOT capped to 1920x1080 !!!!!

Oh and @Dell

STOP TRYING TO DO SOFTWARE LIMITATIONS!!!!!

@Psylocke-X​ 

You're welcome, I am glad it worked :)

Be careful when you install new updates, avoid graphic drivers if you can. Perhaps you should save a copy of the Intel 30.0.101.1338 driver somewhere, just in case.

And make sure Windows Update doesn't interfere, you may want to disable drivers update through Windws Update altogether, this way Windows Update will keep updating the OS but it won't meddle with your drivers.
To do so, go to Start and type gpedit to find the Group Policy Editor: click on it and navigate to Computer Configuration > Administrative Templates > Windows Components > Windows Update where on the righthand side you should be able to find the option Do not include drivers with Windows Update. Enable it. That's it!

About the HDMI cap, well... yes technically the HDMI 1.4 is able to drive up to a 4k screen @30hz, but Dell actually wanted to limit the output to 1080p, I have no idea why, but it is what it is, it's doing it on many entry-level laptops, perhaps to avoid performance issues, who knows... We may never find a way to make other models work at a higher resolution :( 
I always thought Dell had implemented some sort of hardware limitation somewhere between the igpu and the port itself, but in this specific case it would appear to be a software thing! 

@Tatolino​ 

Yeah I stopped Windows from updating drivers by itself no worries, thanks though for the extra information, will surely be handy for a lot of people.

I actually know a lot about PC's, but this issue was the first time I see a manufacturer actually changing how the hardware works, or what it is capable of, via a driver.

I mean, I've seen many times functionality being added by drivers etc, but removing it ... that's something I actually never saw.

Sure, Microsoft removed or modified a lot of handy things in W11 for example, and others sometimes to that with their own software revisions, but that's another thing.

We're talking here about a HDMI port with specifications made by a universal worldwide standard, which is capable of something, and then they start limiting it/removing it with a driver.

Could of course also just be Intel themselves, they're nasty like that too sometimes, like removing AVX support from certain processors etc not so long ago.

Google, Intel, AMD, Nvidia and especially Apple are all professionals in those things.

@Psylocke-X​ 

I totally see your point, and I am too very disappointed with the decision of limiting the output, although I am not privy to the technical motivations behind the choice.

With older Intel integrated solutions it stood to reason that sharing the limited power among the internal screen and an external monitor would take too big of a toll on overall graphics performance.
I would say up to a UHD 630 (10th gen CPUs), while with the 770 and Xe iGPUs this shouldn't be the case.
So maybe this is more of a legacy from older systems... 

Also, generally speaking, there is a limited bandwidth shared between several outputs, so if a UHD 630 can output about 17Gbps, this will have to be split between the screen and the HDMI port. On a laptop with a 1080p screen this won't be a problem, on newer solutions with 2560x1600 screens this might be the reason why they are still limiting HDMIs on newer laptops. 

Go figure... :(

Worked also for me! Thanks a lot!
After to have downloaded both the driver (Version: "30.0.101.1338, A04", Release date: "21 Mar 2022")

and DDU (used v18.0.6.9) I did the following 

1) started windows in safe mode, here how to do it

2) removed the old driver with DDU without restarting the pc

3) again started windows in safe mode

4) installed the intel iris driver

In this way there is no windows update or other things that update drivers in the background also because in safe mode you don't have internet. 

To avoid gpu driver being updated automatically, I followed this guide how-to-stop-windows-from-updating-graphics-drivers

Thanks a lot for this topic!!