I just upgraded from a NUC7i3 to a NUC8i5. I was prepared of some increasement of the fan noise level, but I'm a little surprised how much it increased. I'm wondering if this is right.
Both nucs are on the latest BIOS firmware. Both nucs are running with default BIOS settings.
When turning on the NUC's and entering BIOS setup I notice the following:
NUC7i3: Fan speed 2600 rpm, CPU temp 60C and Memory 50C.
NUC8i5: Fan speed 2000 rpm, no CPU temp, VR temp 32C and Memory 32C.
On the NUC8i5 I have lower fan speed, lower temps, but it is still making a lot more noise. Is this normal?
First of all, there are a whole bunch of NUC models that "NUC7i3" could refer to and a whole bunch of NUC models that "NUC8i5" could refer to. Always refer to them properly so that we don't need to ask. For the past couple of generations, NUC naming has been of consistent form. See here for the details: https://www.intel.com/content/www/us/en/support/articles/000031273/mini-pcs.html. Usually, unless the processor actually matters in your discussion, you can refer to your NUC by its "Family" designation. This is actually a unique, two-character acronym (TLA) for the not-so-Intel-internal code name used during the NUC's design process. For example, the "JY" in "NUC7CJYH" and "NUC7PJYH" stands for June Canyon.
Secondly, do not ever go by what you see (or hear) while in BIOS Setup (Visual BIOS). This is far from being an "Idle" state. While in BIOS Setup, all power management features of the processor are disabled, all interrupts are disabled and thus the processor never halts. It spends most of its time in a spin loop looking to see if there are any events to be processed in the system's hardware. As a result, heat will inconsistently build up in this state. Bottom line, always do your comparisons within the O/S environment and only after the system has been sitting idle for a long while (and never look at a Windows-based system within ~15 minutes of booting).
Third, there is a significant difference between the blowers used in the 7 Series NUCs and the 8 Series NUCs. Those in the 8 Series NUCs are slightly larger and thus do not need to spin quite as fast to push the same amount of air through them. Bottom line, you cannot compare fan speeds in this particular case.
Ok, all that said, please restate your query in terms of the right NUC models and use example readings from a proper comparison situation.
Thank you for your clarification.
Good to know Visual BIOS is not representive.
I will perform several tests later tonight with OS installed and I will post the results.
With regards to the models:
Good to know about the difference in fan size. But you are saying, the 8 Series has a larger fan what do not need to spin as fast to push the same amount of air. Okay I understand this.
What I do not understand, like I wrote in my first post: How can the fan noise be a lot louder than my NUC7i3BNK, while it spins at much lower speed?
The BE blower should not be any louder than the BN blower. Mine certainly isn't. We'll look at this more after you run your tests. Who knows; you may have a bad blower.
I installed Arch Linux on the NUC8i5 and on top of it docker with running some containers. CPU is 98% IDLE for couple of hours, RAM usage 800MB(total available 32GB). The blower doesn't make the same heavy noise as in the visual bios, but:
The blower will start spinning for ~30 seconds, generates noise or airflow noise and then stops for about ~80 seconds and then it goes again spinning for ~30 seconds. This pattern goes on continuously.
The NUC7i3 runs exactly the same OS and kernel, also docker with exactly the same containers, but next to this it runs a virtual machine, with Windows 10, on QEMU. CPU is about 75% IDLE, RAM usage 7300MB (total available 8GB).
The NUC7i3 doesn't generate any noise.