P2419HC, no HDMI signal from your device, #2

@Greg_T  Just to confirm, did you use the same cable when you successfully tested this display on another laptop?  If so, have you tested your Inspiron system using that same HDMI cable connected to a different display (or TV)?  That would help narrow down the problem condition a bit.  And are you just using a standard HDMI cable, i.e. one with HDMI connectors on both ends, and no adapters anywhere?  The reason I ask is that I'm not sure what display output connectors your system has since "Inspiron 17 5000 Series" refers to an entire model line that includes many systems introduced over many years.  It's a bit like saying that you have a "BMW 3 Series".  Your exact system model would be something like Inspiron 5778.

Inspiron 17 5749. DELL-Chris M>

Hi @jphughan,

I used the exact same HDMI cable on both laptops. No adapter of any kind: only a standard HDMI-to-HDMI cable.
I tried to plug an other monitor (a samsung one): the problem is exactly the same. Then the problem must come from some Windows setting.

I checked everything and I don't understand. Both monitors are detected: the Device Manager even shows their names and properties. All graphics drivers are up to date. Windows 10 is up to date.

You summed up the sitauation very well.

I confirm that on two different displays, I can see the displays in Device Manager and Windows Display Settings, but the display itself continues to show "No HDMI input" as if nothing is connected.

I also confirm that when the display is extended, the mouse cursor get lost on the edge where Windows thinks the external display is located. Everything is like if there was a display area.

No error of any kind is thrown. (Except of course the ‘’No HDMI signal from your device’’ on the monitor.)

Nothing additional under the HD Graphics Control Panel: both screens (i.e. the build-in laptop screen and the external monitor) are indeed wired to the Intel GPU (Intel HD Graphics 5500 in this case).

(Just in case it helps, the exact laptop ref is Inspiron 17 5749)

@Greg_T  So on two different displays, you can see the displays in Device Manager and Windows Display Settings, but the display itself continues to show "No HDMI input" as if nothing is connected?  That's very strange.  In Windows Display Settings if you select the external display and then set it to "Extend to this display", does Windows throw an error or automatically revert to some other setting or does it seem to take it?  If the latter, if you then move your mouse cursor off the edge of your built-in display to where Windows thinks the external display is located (normally off the right edge) does your cursor get "lost" over there as if Windows thinks that display is showing active desktop area?

Do you see anything additional under Intel HD Graphics Control Panel (or Command Center, depending on you driver version)?  It's likely that the display outputs are wired to the Intel GPU rather than the NVIDIA GPU in that system, in which case that's where you'd look for any advanced options to manage that display -- not that you should need to mess with any.  One last resort option you could try would be completely uninstalling the Intel Graphics drivers in Programs and Features and reinstalling them from scratch.

@Greg_T  Ok, at this point my only guesses before considering a hardware problem would be either a firmware bug or a driver issue.  For the former, are you running the latest BIOS release for your system?  I didn't see you post your exact system model.  And for the latter, again I would suggest fully uninstalling the Intel Graphics drivers from Programs and Features (not Device Manager), restarting, and then reinstalling them.  I suppose it's possible that there's a bug that still exists in the current release, or possibly even a bug INTRODUCED in a new release -- I am or was recently working on threads where BIOS updates to other systems caused USB-C to DisplayPort video adapters to stop working and a case where an Intel Graphics driver update caused 5120x1440 displays to no longer be operable at that resolution, so it does happen -- but before considering trying older BIOS/driver releases, you may as well make sure you're running the latest and (what should be) greatest version.

Other than that, I just stumbled across this thread, which may or may not be related.  There isn't enough information over there yet, and even the information provided thus far indicates that the scenario isn't precisely the same as yours, but it caught my eye because it's a 5000 Series system, and if it just so happens to be the same generation (which would be the last two digits of the system model), I'll wonder if there's something going on there.  For example, it came out a few months ago that the HDMI outputs of all Inspiron xx93 systems are limited to 1080p, even though they were marketed as having HDMI 1.4 outputs that should support 1440p at 60 Hz or 4K 30 Hz.  Maybe Dell bungled something in the design or manufacturing phase that introduced that unintended limitation, but it just goes to show that sometimes systems of the same generation can exhibit the same issues.  Hopefully a bit more information is forthcoming there.  But for now, I'd try making sure your firmware and drivers are current and performing an uninstall and reinstall.

And absolute worst case, at least as a workaround, if your system happens to have a USB-C port that supports video output -- which is optional and not always implemented on USB-C ports -- then you could use a USB-C to DisplayPort cable to connect to the display, or even a USB-C cable that supports carrying video (also an optional capability on cables) given that your display has a native USB-C input.  That might work even if the HDMI connection is a problem for some reason.  I realize you shouldn't have to do this and that it might involve buying another cable, but I only suggest it as a possible way to get you up and running if the earlier suggestions don't resolve this.