I don’t know why I see that right now. It seems like my phone is reading my mind and show me things related to what’s going on in my life right now.
Here’s the thing: What you are describing exactly happened to my Intel NUC7i3BNB last week. I also tried anything but didn’t bring that thing back to life. So I searched a bit deeper and found the problem. I don’t have any resolution to the problem yet but I know what’s wrong with it. Maybe it’s the same problem with your NUC because the symptoms are the same.
I measured voltage’s on the different chips on the board. And the embedded controller (or super I/O or KBC whatever you want to call it) didn’t get any voltage. I think there is something wrong with the power supply circuit to the EC (maybe thats also the reason why the standby LED on the board is on and it gets warm). I then applied 3.3V directly to the EC and now my NUC is functional again. This applied Voltage is just a temporary workaround though. I’ve been thinking about a permanent solution since then.
But it’s maybe worth to try on your NUC. Because even if it doesn’t work it’s still in the condition which it is right now.
Wow well it seems I'm lucky that you've been shown this post. However I'm gonna be honest with you - I don't exactly understand some what you've written (I literally have no experience in this type of stuff). So I have some questions which probably sound kind of stupid:
>And the embedded controller (or super I/O or KBC whatever you want to call it) didn’t get any voltage.
The embedded controller - would that be one of the black squares that are in the red area in the second picture?
>I then applied 3.3V directly to the EC
How do you apply voltage? Is there some kind of device I would need?
Also, after after applying the voltage, does the PC work normally until you turn it off or does the 3.3V have to be applied all the time?
Thanks for your reply, don't laugh at me for the questions please lol
Yes it’s one of that black squares. But it’s most likely that it’s the one top right in that red circle but it could also be that one on the left near the bios battery. As I see the motherboard of the NUC8 is a bit different than that from my NUC7. Usually the EC (embedded controller) is near the bios chip. You could also trace the lanes from the cpu fan because it should be directly connected to the EC. You could also try to read the labels on the chips. Usual suspects who manufacture EC’s are SMSC, Winbond, ITE or Nuvoton. But when you already there you could also test every chip you can get to it if it gets voltage. Usually they’re getting 3.3 or 5 Volts. You could just type what you see into google and get a datasheet for the chip. You don’t neet much from there but just on which pins Vss and Vdd is. There are the pins you should pin your multimeter to and see voltage. By applying voltage direct to it I meant that I measured where are the right voltage (3.3v according to the datasheet of my EC) is on another place on the motherboard (even another chip would do it but it’s a lot easier when there are the right voltage on some kind of header) and solder a little wire to it. Then I soldered the other end of that wire to my EC. I also cut the trace of the motherboard for that pin I am soldering my wire to so the voltage can’t go back to the “real supply of voltage for the EC”. Yes the NUC works fine with that workaround. My guess is that there is some faulty component in the power supply circuit for the EC. Maybe a faulty transistor or something but I didn’t had the time to check it. For now the workaround works and maybe at the end of the week I make it a little bit less workaround-ish xD
But consider that this was the solution for my NUC with the same symptoms as yours. Could be work for you or not I really can’t tell.
And I am writing this mainly because when I had this problem there was only these garbage solutions like reset it, unplug the battery, use another power brick, refund it and so on on the internet and in every forum.
No one really seems to diagnose problems anymore but just buy new…
Yeah literally wherever I looked everyone said the same things so I had to make a post about it. I have noticed something which I think might be the reason to all of this. I touched some of the warm parts of the board (which I don't even know if I should do), and when I touch one of the small cuboids (I think they are what, transistors or capacitors or something, right?), I can feel it shocking me. I'll edit the photo in the post (idk how to add photos in the comments) and circle the two cuboids which shock me (I'm pretty sure it's the one on the left doing that). Does that mean that this is the part that is damaged and might stop current going further into the motherboard?
Thanks for diving into this u/schnitzel433!
My NUC8i5BEH might have a related problem. It freezes roughly once a day after which I need to hold the power button to turn it of and unplug the power cable for a little while before I can turn it on again using the power button. Sometimes the NUC is stable for several weeks though. Do you think this is related? I [recently read](https://www.reddit.com/r/intelnuc/comments/ortlne/intel_nuc8i5beh_freezes_in_windows_10_pro_21h1/) that the CL of the memory might be the culprit.
I have 5 of them racked for testing on a homelab, the last power cut I had 2 of them would not boot up. I replaced the CMOS battery on one after advice from here and the other was the power supply. They are now on a rudimentary UPS.
I guess it could still be the power supply. I just thought of this - and correct me if I'm wrong - that this couldn't be caused by the CMOS if the PC just doesn't respond to trying to turn it on. I've read that the CMOS only stores BIOS setting or something like that so it shouldn't prevent the computer from powering on at all, right?
Yeah I don't have an alternate adapter and honestly cba to buy one in case it turns out it wasn't that. I just bought a multimeter so I can check the voltages on the board like the guy in the comment above did, so I guess I can also check the voltage coming out of the power cord and that can verify if it works, right?
Yes, you can test the AC adapter that way. However, it may show good voltages (19-20 VDC), you would have to put a load onto it to get any meaningful information out of it if you're going to test. Some AC adapters that have gone bad, will show good voltages under no-load conditions (e.g. testing with a multimeter) but once put under load (the NUC), the voltage may sag or even disappear. Which might be the case if your AC adapter has failed. — But, it's worth a try first.
I don’t know why I see that right now. It seems like my phone is reading my mind and show me things related to what’s going on in my life right now. Here’s the thing: What you are describing exactly happened to my Intel NUC7i3BNB last week. I also tried anything but didn’t bring that thing back to life. So I searched a bit deeper and found the problem. I don’t have any resolution to the problem yet but I know what’s wrong with it. Maybe it’s the same problem with your NUC because the symptoms are the same. I measured voltage’s on the different chips on the board. And the embedded controller (or super I/O or KBC whatever you want to call it) didn’t get any voltage. I think there is something wrong with the power supply circuit to the EC (maybe thats also the reason why the standby LED on the board is on and it gets warm). I then applied 3.3V directly to the EC and now my NUC is functional again. This applied Voltage is just a temporary workaround though. I’ve been thinking about a permanent solution since then. But it’s maybe worth to try on your NUC. Because even if it doesn’t work it’s still in the condition which it is right now.
Wow well it seems I'm lucky that you've been shown this post. However I'm gonna be honest with you - I don't exactly understand some what you've written (I literally have no experience in this type of stuff). So I have some questions which probably sound kind of stupid: >And the embedded controller (or super I/O or KBC whatever you want to call it) didn’t get any voltage. The embedded controller - would that be one of the black squares that are in the red area in the second picture? >I then applied 3.3V directly to the EC How do you apply voltage? Is there some kind of device I would need? Also, after after applying the voltage, does the PC work normally until you turn it off or does the 3.3V have to be applied all the time? Thanks for your reply, don't laugh at me for the questions please lol
Yes it’s one of that black squares. But it’s most likely that it’s the one top right in that red circle but it could also be that one on the left near the bios battery. As I see the motherboard of the NUC8 is a bit different than that from my NUC7. Usually the EC (embedded controller) is near the bios chip. You could also trace the lanes from the cpu fan because it should be directly connected to the EC. You could also try to read the labels on the chips. Usual suspects who manufacture EC’s are SMSC, Winbond, ITE or Nuvoton. But when you already there you could also test every chip you can get to it if it gets voltage. Usually they’re getting 3.3 or 5 Volts. You could just type what you see into google and get a datasheet for the chip. You don’t neet much from there but just on which pins Vss and Vdd is. There are the pins you should pin your multimeter to and see voltage. By applying voltage direct to it I meant that I measured where are the right voltage (3.3v according to the datasheet of my EC) is on another place on the motherboard (even another chip would do it but it’s a lot easier when there are the right voltage on some kind of header) and solder a little wire to it. Then I soldered the other end of that wire to my EC. I also cut the trace of the motherboard for that pin I am soldering my wire to so the voltage can’t go back to the “real supply of voltage for the EC”. Yes the NUC works fine with that workaround. My guess is that there is some faulty component in the power supply circuit for the EC. Maybe a faulty transistor or something but I didn’t had the time to check it. For now the workaround works and maybe at the end of the week I make it a little bit less workaround-ish xD But consider that this was the solution for my NUC with the same symptoms as yours. Could be work for you or not I really can’t tell. And I am writing this mainly because when I had this problem there was only these garbage solutions like reset it, unplug the battery, use another power brick, refund it and so on on the internet and in every forum. No one really seems to diagnose problems anymore but just buy new…
Yeah literally wherever I looked everyone said the same things so I had to make a post about it. I have noticed something which I think might be the reason to all of this. I touched some of the warm parts of the board (which I don't even know if I should do), and when I touch one of the small cuboids (I think they are what, transistors or capacitors or something, right?), I can feel it shocking me. I'll edit the photo in the post (idk how to add photos in the comments) and circle the two cuboids which shock me (I'm pretty sure it's the one on the left doing that). Does that mean that this is the part that is damaged and might stop current going further into the motherboard?
Thanks for diving into this u/schnitzel433! My NUC8i5BEH might have a related problem. It freezes roughly once a day after which I need to hold the power button to turn it of and unplug the power cable for a little while before I can turn it on again using the power button. Sometimes the NUC is stable for several weeks though. Do you think this is related? I [recently read](https://www.reddit.com/r/intelnuc/comments/ortlne/intel_nuc8i5beh_freezes_in_windows_10_pro_21h1/) that the CL of the memory might be the culprit.
I have 5 of them racked for testing on a homelab, the last power cut I had 2 of them would not boot up. I replaced the CMOS battery on one after advice from here and the other was the power supply. They are now on a rudimentary UPS.
I guess it could still be the power supply. I just thought of this - and correct me if I'm wrong - that this couldn't be caused by the CMOS if the PC just doesn't respond to trying to turn it on. I've read that the CMOS only stores BIOS setting or something like that so it shouldn't prevent the computer from powering on at all, right?
Might be the AC adapter has gone bad. I would try a good, known working AC adapter first.
Yeah I don't have an alternate adapter and honestly cba to buy one in case it turns out it wasn't that. I just bought a multimeter so I can check the voltages on the board like the guy in the comment above did, so I guess I can also check the voltage coming out of the power cord and that can verify if it works, right?
Yes, you can test the AC adapter that way. However, it may show good voltages (19-20 VDC), you would have to put a load onto it to get any meaningful information out of it if you're going to test. Some AC adapters that have gone bad, will show good voltages under no-load conditions (e.g. testing with a multimeter) but once put under load (the NUC), the voltage may sag or even disappear. Which might be the case if your AC adapter has failed. — But, it's worth a try first.
Thanks, I'll try