Dell 3593 with nvidia mx230 - 4k not working

@PatrykSzczepanski  even if your system has an NVIDIA GPU installed, it's likely that the display outputs are still physically wired to the Intel GPU while the NVIDIA GPU uses NVIDIA Optimus to operate as a render-only device only when needed.  The reason I bring this up is that this is the third thread and the third system in recent memory where people have reported this exact issue of 4K output not being available over HDMI and the system only allowing up to 1080p.  This thread involves an Inspiron 3493, rather similar to your 3593, and this thread involves an XPS 15 7590.  I'm wondering if the fact that these have all appeared just recently speaks to a problem with a recent Intel Graphics driver release or something.  The only alternative would be some firmware/hardware problem with the HDMI output that's common to all of these systems.

I'm going to send these threads to a Dell rep on this forum who's been successful in the past escalating reports like this to the appropriate Engineering teams within Dell and either getting fixes developed or at least getting KB articles published acknowledging the issue.

I just heard back from @DELL-Justin C , who is the person I said I would PM in my post above. He asked me to tag him in this thread, so I've done that.  Hopefully he'll have an update to share in this thread soon.

@PatrykSzczepanski  I was hoping that DELL-Justin C would respond here, but that seems not to have happened.  What he told me via PM was that after checking internally within Dell, he found internal documentation indicating that Inspiron xx93 systems, which would include this 3593, were limited to 1080p on HDMI.  I asked what the source of this limitation was given that Intel GPUs have supported 4K 60 Hz for over 6 years now, and the HDMI port is specifically indicated as HDMI 1.4b, which supports 1440p or 4K 30 Hz.  He said he'd look into it, but now he's followed up advising that the documentation team within Dell has opted to keep that documentation internal, but that he will be pushing to get some sort of note about this limitation added to the system documentation.

I have to say I'm personally disappointed with Dell on multiple levels here, which is why I replied with the following:

"And the answer as to the underlying cause that you said you'd ask about?  Has Dell decided to keep that under wraps too?  So this is basically an EXACT repeat of how the issue with the XPS 13 9350 not sending video over USB-C to Dell's own USB-C displays was handled?  Dell's response to that was to do nothing except put up a KB article acknowledging the issue -- a KB that not only failed to identify the underlying cause, but even had the gall to say "We're not going to fix it because we consider that system old, but you can work around it by spending more money on one of our docks."  And now with this issue, the most Dell will apparently consider doing is adding a note about this to the documentation of these systems, which again doesn't identify underlying cause and will do precisely NOTHING to help the people who already own them?  And let's not lose sight of the fact that those customers could certainly be forgiven for not expecting a limitation like this, given that Intel GPUs have supported up to 4K 60 Hz going back at least 6 years now.  So on top of Dell being cagey about sharing any information about this, there's the issue that somebody implemented some boneheaded design in these systems that severely crippled the display output capabilities of the platform.  And finally, there's the fact that the system specs specifically mention "HDMI 1.4" rather than just "HDMI".  HDMI 1.4 supports 1440p 60 Hz or 4K 30 Hz, so given that Dell made a point of identifying the port's revision in its documentation, it's reasonable for customers to expect that the revision actually speaks to the system's capabilities -- except in this case, the system can't actually do things that an HDMI 1.4 output can normally do, which means it is pointless and misleading to call out HDMI 1.4 on these systems.

I know this wasn't your call, but as someone who's been a great deal of my time on a volunteer basis here trying to help people out, it's disheartening to see the people within Dell who get paid to serve customers respond in these shady and completely unhelpful ways."

Sorry I don't have a better answer for you here Patryk, and I'm even more sorry that Dell themselves hasn't given you an answer at all.  I hope Dell decides to do better for their customers.