NUC working fine for a few years, but suddenly no HDMI signal
Hi, my NUC7i7DNK worked fine for a few years as a media PC connected to a 75" TV. Now when I came home from a week vacation the NUC do not seem to give any HDMI screen signal any more. I have tried another HDMI cable, I have got another PC to view sccreen on the same HDMI port on the TV. Restart of the NUC does not help... When I restart the NUC the power LED blinks a few time and end up having orange continuous light. The TV seems to notice that the NUC HDMI cablle is connected (because that HDMI input nuber is showing n the TV but TV still says no signall). Disconnecting the NNUC HDMI makes the HDMI input disappaer from the TV screen. Connecting another PC it shows the screen on the TV. What error/fautt suddenly appaering can cause such behaviour?
Try opening up the NUC and checking the RAM. If there are multiple SODIMM modules installed, remove them one at a time to help isolate any potential memory issues.
Thank you for replying. I was also thinking about faulty RAM as a possibility for the NUC not even to be able start BIOS etc. For up to now, as soon the NUC was starting BIOS the screen have usually appeared on the TV-screen. However not easy to test removing RAM one by one as it is only onle RAM module in this NUC ;) I will need to get another module to test with. I have another NUC and will check this evening if the modules are similar.
Ah... my other NUC is obviously older and has DDR3 RAM instead of DDR4 as the newer faulty has. So I might have to buy a new module.
BTW, I've also seen some comments in other forums that a situation with NUC's not booting and not showing a screen have been solved by others by removing the CMOS battery for 15 minutes and reconnecting it. Might perhaps be something to try.
This behavior usually points to a graphics output or firmware issue, not the TV or cable. On NUC7i7DNK, a solid amber/orange LED often indicates the system is powered but not completing normal initialization. Common sudden causes include BIOS corruption, CMOS battery failure, or HDMI port/IGPU failure.
An amber power light indicates that the PC is not passing POST (Power on Self Test). This could be due to a corrupted BIOS.
According to the manual for a NUC7i7DN PC there's a CR 2032 type RTC coin cell battery on the motherboard.
Hopefully it will be the same in your version.
If there is, disconnect the power to the PC and remove the coin cell battery from the motherboard and then press and hold the Power button operated for a full 30 seconds and then release it.
When the battery is out, measure its voltage. If it is <2.5V DC or if the battery is >3 years old, replace it. CR2032 batteries are commonly available everywhere, e.g. supermarkets.
Reinsert the RTC coin cell battery back into its holder on the motherboard (+ve side up as marked on the battery), reassemble the PC, reconnect the power to the PC and check if it now turns on OK with a display etc.
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7 Commenti:
Yes it was a CR 2032 and measuring with a multimeter the battery voltage was 3,1 V. I had no new battery at hand but 3,1 V is not low.
After disconnecting power cable and battery I held the power button in for more than 30 seconds. Afterwords alsoI swapped the old RAM module with a new one (afterwords I tried the old one too). Unfortunately removing the battery nor trying another RAM module worked for getting this NUC to start.
Now I have tried the other HDMI port on this NUC and still nothing on the screen. As mentioned the fan starts when I turn the NUC on but stops (or slows down a lot) after a while and with amber power button LED. I took a photo of the motherboard (MODEL or SERIAL NUMBER?)
I can't find a schematic for the board but was wondering if an option is to try updating the BIOS. (see p.73 of this manual. Hopefully the procedure is the same for your model as I couldn't find the same guide for it.
Intel has stopped product support but I found your model on an Asus support page.
If you can't get into BIOS or the update doesn't even start then I don't know.
I had the same issue as you a couple of days later (26.01.2026), None of the two HDMI ports were working, and the screen (A Samsung LF27T370FWRXEN) worked fine on other devices. What i found as a work around was connecting the HDMI cable to a HDMI-USBC converter (I have one with HDMI, USB-C, USB and VGA -ports, but im sure any dongle will work. Just google "hdmi usbc dongle") and then i got picture. I did some digging in to the computer and noticed an update was installed the day before. Specifically this update:
First thing i did was i uninstalled the graphic drivers, installed Intel's Arc control panel (I believe i got them from my NUC's support page directly) and reinstalled the graphics drivers through this control panel. And i did an BIOS reset with the taking out of battery. I also installed Intel's Driver and Support Assistant: https://www.intel.com/content/www/us/en/...
Nothing helped until i started working on the rollback of Windows Updates within Windows it self. I rolled back that Windows Update (KB5078127) , and even two more previous KB-updates, reinstalled the first one from: https://www.catalog.update.microsoft.com... and then i let "Windows Update" handle the rest.
Not until "Windows Update" had done its thing did the HDMI port start working again.
It has been working until today and we are back to where we where, HDMI ports stopped working again. But the USB-C ports (assumingly Thunderbolt ports) works as an screen port with a dongle. I see there is a couple of security updates rolled out earlier in the day today, yesterday and the day before (We haven't used this computer in 2 days, so that's why i mention all the updates the past 4 days), Specifically these updates:
Was installed on 11.03.2026:
Security update for Microsoft Defender Antivirus – KB2267602 (versjon 1.445.470.0)
Security update for Microsoft Defender Antivirus – KB2267602 (versjon 1.445.482.0)
Was installed on 12.03.2026:
Security update for Microsoft Defender Antivirus – KB2267602 (versjon 1.445.492.0)
Was installed on 13.03.2026:
Security update for Microsoft Defender Antivirus – KB2267602 (versjon 1.445.511.0)
Security update for Microsoft Defender Antivirus – KB2267602 (versjon 1.445.513.0)
Was installed on 14.03.2026:
Security update for Microsoft Defender Antivirus – KB2267602 (versjon 1.445.529.0)
For now i will wait for the next update and see if it fixes it self, but i just wanted to mention my fix the last time the issue happened. For now i will just use the HDMI-USBC dongle.
Its worth mentioning that i have an Intel Nuc i5, Model number: NUC11TNK
Its also worth mentioning that i reseated the RAM, the NVME, factory reset my screen and i checked the legs on both of the HDMI ports on the motherboard under an microscope, and it all looked fine to me. I also installed this Intel program that can make the NUC play picture over the network to another screen, but i ended up uninstalling it since it didn't fix anything and seemed useless for us. And i tried different HDMI cables, but ended up putting back the old HDMI cable since i could find any issues with it. What was actually the fix for me is somewhat uncertain but it feels like the Windows Update rollback was the main fix, or an combination of all of the above.
I hope any of this info helps you or anyone else out.
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Hi, my NUC has been "resting" on the shelf since I replaced it with another NUC some weeks ago. Your comments did however give me some hope to get my NUC7i7DNK up running again. I will start by getting a HDMI to USB C adapter and test on the only screen I have (Curved Ultrawide) with USB C Screen signal input. This screen port can also power a laptop from the screen -> Thunderbolt).
I don't have any use for that NUC on that particular screen, but it might be a good start to check if the NUC actually works (Motherboard, RAM, and everything else) and that it may be only a software (update) problem as you have described on your NUC.
Hi, one more thing, did you connect the USB C adapter to the NUC and the HDMI cablt to the screen or was the HDMI cable connected to a HDMI port as before and the USB C to a screen?
Yet another question, Would a Windows update (KBxxxxxxxx) be able to screw up so that the HDMI port connected screen no longer show the BIOS startup? Wouldn't a windows change only affect the screen after Windows start up?
@helge240 My solution is just a theory. But yes I had the same issue where the screen wouldn't even show during POST.
I used the hdmi adapter on the nuc, not the screen.
My theory is that an update screws with the HDMI handshake between the screen and the port, hence why the same cable worked with an adapter.
Also rolling back updates and screwing around with drivers also fixed the issue for a while.
If you can change the HDMI version directly on the screen then that might work for you.
I ended up just changing the HDMI cable to an older version (HDMI 1.2 i believe) and that worked for me (without using the adapter) since even the adapter workaround stopped working for me after about a week after I posted this solution.
@helge240 It could also just so happen to be an bad cable that just happened to work every time it was put in a very very very specific angle, but I doubt it since the screen and cable is basically brand new, and the system is stationary (doesn't get moved around very much, basically not at all).
And I could not seem to recreate the issue after it stopped working, by trying to change the angle of the cable. I even tried to change the angle when it was connected with the adapter (both when the adapter solution was working, and when adapter solution stopped working) just to see if the screen would flimmer, but nothing, no change.
My gut feeling says that this is an software issue (that came through an windows update/grafic drivers lagging behind the windows update) that goes all the way down to BIOS level where there is some sort of handshake issue with the signal versions on the port it self. But ofc I might be wrong.
4 Commenti
Hi @helge240,
Try opening up the NUC and checking the RAM. If there are multiple SODIMM modules installed, remove them one at a time to help isolate any potential memory issues.
da Augustine
Thank you for replying. I was also thinking about faulty RAM as a possibility for the NUC not even to be able start BIOS etc. For up to now, as soon the NUC was starting BIOS the screen have usually appeared on the TV-screen. However not easy to test removing RAM one by one as it is only onle RAM module in this NUC ;) I will need to get another module to test with. I have another NUC and will check this evening if the modules are similar.
da Helge
Ah... my other NUC is obviously older and has DDR3 RAM instead of DDR4 as the newer faulty has. So I might have to buy a new module.
BTW, I've also seen some comments in other forums that a situation with NUC's not booting and not showing a screen have been solved by others by removing the CMOS battery for 15 minutes and reconnecting it. Might perhaps be something to try.
da Helge
If your NUC was working fine for years and suddenly shows “No HDMI Signal”, try these steps to fix the issue:
Turn off the NUC and unplug the power for 2–3 minutes.
Check the HDMI cable and try a different cable if possible.
Connect the NUC to another monitor or TV to test the display output.
Try a different HDMI port on the monitor.
Remove all external USB devices and restart the NUC.
If the power light turns on but there is still no display, try resetting the BIOS:
Disconnect power
Open the NUC case
Remove the CMOS battery for a few minutes
Reconnect and start again
Make sure the RAM is seated properly; loose RAM can also cause no display issues.
If none of these steps work, the HDMI port, motherboard, or graphics hardware may have developed a fault after long-term use.
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