Kaby Lake i7 NUC Review 4/4: Fan, Power, Linux, Conclusions (NUC7i7BNH)
Keeping a hot Core i7 CPU cool in a tiny enclosure is a difficult task and Intel has not always seen stellar success in that. Some might remember that the fan behaviour of the NUC5i7RYH back in 2015 was quite interesting. The fan went from idle to full speed in a second as soon as all cores were being utilized. It did sound like a jet engine too soon and at least for me was the most significant turn off with that model. The Skull Canyon NUC in 2016 was quite a bit better in that case. However, you wouldn’t classify that one as a quiet PC either.
What about the NUC in question here, the NUC7i7BNH? Well, I’d say it’s on par with the Skull Canyon. The 28W Core i7 CPU has been crammed in almost the same enclosure that works wonders with the 15W Core i3 and i5 models. As a result the small fan does spin up more often and you can hear it. I’m pretty allergic to fan noise and really would not like to put one on my desktop where it’s clearly audible. Your mileage may vary though. Maybe attached behind a monitor it’d be more quiet?
Due to popular request I’ve actually bought a cheapo UNI-T UT353 sound meter to get you some actual figures. All my testing is done at my home with ventilation turned off. I’m pretty sure that my completely unscientific approach is quite laughable for the people who actually do this kind of thing for living. I’m also pretty sure that the numbers produced are not comparable with numbers produced by someone else in their tests. I’ve measured from the front of the NUC with the microphone of the meter 50 cm away from the front panel. I’ll try to do so with my future NUCs so hopefully the numbers can be compared between my measurements.
|Power off (noise floor)||33.3 dB|
|Windows 10, idle on desktop||35.6 dB|
|Prime95 running stress test on all cores
(CPU temperature 86 degrees C)
|3DMark Time Spy Demo
(CPU temperature reaches 100 degrees C occasionally)
|37.0-44.1 dB, mainly around 37-38.5 dB,
but occasional peaks at 44.1 dB
It’s worth noting that 39 decibels is really quite much more than 33 decibels even if the numbers do not seem so much different. When the power of a sound source is doubled the sound level increases by 3 dB.
I’ve also bought a watt meter to provide you some power consumption figures! The following figures were measured using a Brennenstuhl EM240 watt meter.
|Windows 10, idle on desktop||13.7 W|
|Prime95 running stress test on all cores||48.6 W|
|3DMark Time Spy Demo||58.5 W|
|MPC-HC playing 10-bit 120Mbps HEVC at 4k||33.5W|
I never saw the NUC break the 60-watt mark and that makes sense as the power supply is rated up to 65 watts. Stressing both the CPU and the GPU simultaneously seems to be the way to reach peak consumption.
Due to the latest Intel GPU and the WiFi chip you’ll need a fairly recent kernel. I’m mainly a Ubuntu-man so I did install the Ubuntu 16.10 on the NUC. The kernel on the long-term supported 16.04 version does not fully support Kaby Lake.
Anyhow, the installation was fine. GPU, WiFi, Bluetooth, Ethernet adapter were all working fine. Bitstreaming of HD audio formats to an amplifier does not work on any Apollo Lake or Kaby Lake NUCs (problem exist on ASrock/MSI and other products with similar components as well) when connecting via the HDMI 2.0 port. There’s a long-running bug report here.
For those who are interested, the complete boot log is here.
The Kaby Lake i7 NUC is the fastest NUC available in the traditional 4×4 form factor. It’s also the NUC with the fastest single-core CPU performance. However, it only has two cores (with hyperthreading) so it cannot match the performance of the quad-core Skull Canyon NUC in multi-core tasks.
Allright, but what do I think about the Kaby Lake i7 NUC? I say it’s sandwiched into a difficult position. On the other hand the 15W Kaby Lake i5 will most likely provide only slightly worse performance with much less fan noise. Then again, the Skull Canyon NUC provides significantly better performance for only a small increase in price. Pretty much the only thing the Skull Canyon NUC does not do vs. this one is the 10-bit HEVC video hardware decoding.
- Fastest NUC available in this form factor
- Thunderbolt port provides flexibility
- The fan is still rather noisy under heavier CPU loads
- Not that much more performance when compared to Skylake i5 NUC (and most likely the Kaby Lake i5)
- Micro SD card reader not as useful as SD card reader on the previous gen
This time the recommended setup has 16 gigabytes of DDR4-2133 RAM that is known to work well in this NUC and an ultra-fast 250-gigabyte Samsung NVME SSD drive. It leaves you the 2.5″ slot empty for another drive. If you would like to equip your NUC in a different way, have a look at our build-a-NUC tool: the NUC Guru.