Skylake i5 NUC Review (NUC6i5SYH / NUC6i5SYK) – Part 1/3: Overview

A couple of weeks ago I reviewed the Skylake i3 NUC that hit the shelves around Christmas. Today it is time to look at the big brother of that model, the Core i5-powered NUC6i5SYH. We found out that the i3 model was performance-wise a surprisingly large upgrade over the previous generation model, so we had high hopes that its i5-powered sibling would surprise us equally positively. Do note that the other Skylake i5 NUC, NUC6i5SYK, is the model that has a more sleek chassis but no space for a 2.5″ drive. Otherwise the units are the same – same mainboard, same CPU, same performance.


  • Intel Core i5-6260U Processor, 2.8GHz, dual-core, 15W TDP
  • 2 slots for DDR4-2133 SO-DIMM memory, 1.2V, max. 32GB
  • Normal, full-size HDMI 1.4b port
  • Mini DisplayPort 1.2 port
  • Intel Iris Graphics 540 GPU, 48 EUs, 64 MB eDRAM cache
  • Four USB 3.0 ports (2 on the front, 2 on the rear)
  • Intel I219V Gigabit Ethernet LAN adapter
  • Intel Wireless-AC 8260 WiFi adapter (802.11ac, dual-band, max. 867 Mbps, Bluetooth 4.1)
  • Support for M.2 SSD card (sizes 22×42 and 22×80)
  • Slot for a single 2.5″ drive (SSD or HDD, max. 9.5mm thickness)
  • SD card reader (support SDXC cards and UHS-I)
  • Infrared sensor and 3.5mm audio jack

Technical product specification (PDF) is available here.


From outside the Skylake i5 NUC is identical to the i3 model. It’s also very similar to the previous generation Broadwell NUCs. Each unit has the already-familiar glossy black plastic top cover (that inevitably gets scratched – keep the plastic film on it until you’ve finished installing the components) and an aluminium chassis. Dimensions haven’t changed either: 115 x 111 x 48 mm or 4.5″ x 4.4″ x 1.9″. The NUC6i5SYK model would be slightly smaller: 115 x 111 x 32 mm or 4.5″ x 4.4″ x 1.3″.

On the front of the NUC we now have a blue front panel power LED between the IR receiver window and the 3.5mm audio jack. When the NUC is sleeping, this LED will be blinking in orange color. You also have two USB 3.0 ports, out of which the yellow one is fast charging capable.

Behind the NUC we find the usual connectors with again one small change: the HDMI 1.4b port is now a full-sized port instead of the mini HDMI port found in the previous generations. The rest of the ports are the same: 19-volt DC input, RJ-45 for Gigabit Ethernet, two USB 3.0 ports and a Mini DisplayPort 1.2.

On the left side there’s the integrated SDXC card reader that made its debut in the Braswell NUC earlier in mid-2015. It supports UHS-I cards, but UHS-II cards will only work on the UHS-I level (theoretical maximum 104 megabytes per second).

If you’re interested in the unboxing, have a look at the YouTube video below. It’s been created for the NUC6i3SYH, but the NUC6i5SYH unboxing would be totally identical – the contents of the box are the same.

What’s Inside?

The Skylake NUC is delivered without memory and storage media included. For memory you should choose either 4, 8 or 16 gigabyte memory modules, although at the time of writing this article 16GB modules were next to impossible to find. There are two slots available and even if you can populate only one of them, you should definitely consider installing two similar memory modules for optimal performance. The memory module must be a 1.2 volt DDR4 SO-DIMM module, and if this one is anything like its predecessors it can be a bit picky regarding the compatible memory modules. For this review I used the Kingston HyperX HX421S13IBK2/8 which is a 2-module kit with total capacity of 8 GB. If you want to be sure that you get the right kind of memory module go see the NUC Guru – our resident guru who can suggest you hardware that definitely works together.

Skylake i5 NUC with components installed

Skylake i5 NUC with components installed

After removing the four screws that secure the bottom cover to the chassis, you can immediately access the mainboard. The NUC6i5SYB mainboard is used for both NUC6i5SYH and NUC6i5SYK models. The difference is that NUC6i5SYH has a slot for a 2.5″ drive in the bottom cover and the SATA cables that connect to the mainboard. NUC6i5SYK has the SATA connectors on the mainboard, but does not come with any of the cabling supplied. For this review I installed a cheap Sandisk 128GB SSD drive in the 2.5″ slot.

It’s really quite impressive how much Intel has managed to pack on this tiny motherboard. You’ve got two DDR4 memory slots dominating the bottom of the above picture. Skylake is the first NUC to use DDR4 memory, so you cannot simply upgrade from previous generations and move your memory to this NUC.

At the top you can see the M.2 slot. It supports PCI Express 3.0 specification and up to x4 bandwidth. When using a fast PCIe-based SSD drive the maximum bandwidth is limited to about 1600 megabytes per second according to Intel. You can also use a cheaper, standard M.2 SATA SSD drive in which case the maximum bandwidth is about 540 MB/s. The M.2 card used should be either 22×42 or 22×80 in size. 22×60 cards are not supported. As you can see, a 22×80 card will be physically above the SD card reader and the WiFi adapter – there’s no space for a mounting screw for 22×60 cards. Possibly you could use a 22×60 card with a 3rd party adapter. The 802.11ac WiFi adapter is soldered to the mainboard and not replaceable.


The device runs Intel’s usual Visual BIOS. It’s not the nicest or most flashy, but does its job. As usual, I reduced the minimum fan speed a bit to 25% in order to make the NUC a bit more quiet. While it’s not noisy out-of-the-box by any means, making this change turns it almost silent. BIOS version 28 was preinstalled in the NUC and as that is the latest that’s what was used for this review.

Windows Installation

Windows 7

Windows 7 installation image does not have any USB 3.0 drivers. This is a problem, because the Skylake NUC only has USB 3.0 ports, so you cannot use your USB mouse or your USB keyboard during the installation and what other options do you have?! You will need to modify the installation image in order to complete the installation.

I wrote an article on how to prepare the Windows 7 installation for USB 3.0 support, but you can nowadays also use Intel’s Windows 7 USB 3.0 Image Creator tool, which basically does automatically all the steps I described in that article.

When you finally have Windows 7 up and running you will not have any network connectivity. What you need to do is to download the WiFi/LAN drivers on another PC and move them to your NUC (on a USB stick for example) and install. When you get network connectivity, you should spend a few hours downloading the latest Windows patches. In the end when all is said and done, you’ve got a working Windows 7 system and everything runs smoothly.

Windows 10 Installation

These days I use Windows 10 instead of Windows 7, so that’s what I tried to install next. I used Windows 10 November 2015 image, also known as version 1511, and installation itself was uneventful and as expected. However when the system was up and running a driver from Intel’s download center was needed for both the WiFi and Ethernet adapters before the system was fully usable. When the networking was up and running Windows automatically installed the necessary drivers for rest of the NUCs components. However, the display driver was slightly outdated version, so I replaced the driver with a newer one from Intel’s support website.

Read Further

The next parts of the review:

57 Responses

  1. John Boero says:

    Excellent review thanks!
    I just got mine and had 2 minor issues: Samsung 16GB DIMM doesn’t seem to work in it. Just get 3 flashes of the LED. Also I can’t seem to get into the visual bios settings, so I flashed the latest SY0033 BIOS. On reboot I can no longer see my internal MSATA SSD which contained boot partitions. Now I’m unable to flash back SY0028 BIOS without doing some “Recovery BIOS” to downgrade. Oy ve.

    • Olli says:

      That’s doesn’t sound too good, John. Try to clear the CMOS or perform a BIOS recovery, as you say. And thanks for the heads up that there is a BIOS version 33 – I had not noticed that one.

  2. Ted says:

    I set mine up today and lost my M.2 SSD after updating the BIOS to “33”. A couple of very stressful hours later, trying EVERYTHING, I noticed an unchecked checkbox in the Visual BIOS above where it showed the M.2 not installed. Checked it, rebooted, and all was well. Whew! That scared me.

    Skyrim auto-sets quality to High, 1920×1080, and it runs smoothly. I turn off the AA since I’m using a 4k monitor.

    Very happy with my NUC6i5SYK so far… minus the vanishing SSD episode!

  3. Sam says:

    In Windows 7 there is no Startup Sound. And some Games have no Sound in fullscreen Mode. The Drivers for Windows 7 are terrible.

  4. Nick says:

    Is it possible to use higher frequency ram (2400MHz) than 2133MHz or reduce the timings in the BIOS options?

    • Sam says:

      No There are no options line the previous NUC. I buy a g.skill kit 2×4 GB 2400mhz ram. I can only set the multiplier to 133mhz. Like 16x 133mhz. and Thats the Max. No Option to set 24x 100mhz or go even higher than 16x133mhz.

  5. Sam says:

    U can Try to reduce the Timings. But there Are no the Effekt u can feel. In the previous NUC Generation the NUC 5i5ryk i put a g.skill RAM kit in to it with 2133mhz with this config the Bandwith of the Iris 6000 go up to 32gb/s. I set Customer multiplier to 20x100mhz. With this Setting the Bandwith go up to 47gb/s and Thats a big difference in Gaming.

    To push the 6i5syk Model go in BIOS to power Settings. And set the TDP from 26 Watts to 30watt. The Turbo is Already config to 30 Watts.

    • Brian says:

      So…Sam, will NUC6i5SYH work with 2x16GB 2400MHz DDR4 (HyperX) @ 2133 (as this would be the max clock for this model)?!? Or do I have to buy the 2×16 2133MHz DDR in order for the system to work. The only reason I’m asking is the fact that there is a minor supply problem for the 2x16GB @2133 kit (HyperX at decent prices), whilst the 2x16GB @ 2400MHz kit is still available in a few online shops at decent prices.

  6. J H says:

    Can anyone confirm that you can get the best speeds capable from the Samsung M.2 950 pro? Here is a relevant post I made on Reddit about the issue.
    Apparently the pci express slot on the 5thb gens can’t support the speed. I’d like to upgrade but only if I can get the most performance out from this SSD.

  7. Markus says:

    Half a day hassle with NUC6i5SYH later…
    Does anyone successfully installed Windows 7 on M.2 ssd (Samsung 950 Pro) ?

    First step to inject usb3 drivers are made.
    No harddrive (ssd) is listet in Windows 7 setup :-(
    tried -> F6 with Intel rst drivers also.

    Help appreciated.

  8. Anthony says:

    Has anyone tried running Server 12 on the NUC6i5SYK by chance? I can’t seem to get anything to install without having to disable integrity and enabling testing. It’s the main reason I bought the thing and I done nothing but fight every single driver with it.

  9. Will says:

    Great review, thank you! Set up my NUC6i5SYK with Win 10, and all went smoothly (except one crashed BIOS screen – bit odd). Can anyone see any downside to setting the minimum fan speed to zero? It seems to not run too hot, and will kick in if needed. Would be quite nice to have it running silent, but slightly wary in case there is some reason I shouldn’t. Any thoughts?

  10. Sam says:

    Running with a 512GB Samsung V-NAND SSD 950 Pro M.2, two 16GB M471A2K43BB1 SoDIMMs from Samsung and Windows 10. Running the latest BIOS.
    My first concern was fan noise. I am not a gamer. Running two Windows 7 virtual machines under VirtualBox. So far I have not heard any loud noises from the fan. Though its not my normal workload, I did try running a 4K video from Youtube while VirtualBox VMs were running. Again no issues. I can see the CPU frequency changing dynamically but overall load was about 20% at different frequencies. The CPU does revs up for few seconds when application is launched but comes down immediately.
    When is it extremely quiet, you can hear the feeble humming noise from the box. I don’t quite like that but I can live with it.
    Its driving the 34inch widescreen monitor with no issues.
    The SSD is giving 1.5GB/S Read/Write on average. 1.5GB is more like the ceiling though. I was using Disk test from BlackMagic Design.
    Having a lot of Windows 10 issues. The chipset driver would install but will not showup in “programs installed” window. Though I did confirm from the registry that it is installed. Also having installation issues with other drivers downloaded from Intel.All the devices are discovered properly though under Devices tab. Wakeup from Sleep is not quite working. Getting garbled window screen. Had to reboot.

    • Olli says:

      Thanks for your comments Sam,

      I’ve got sleep working just fine. There’s someone here reporting issues with that Samsung memory:

      Not sure if that’s the reason for any of the issues you see, but something to keep an eye for sure.

      • Sam says:

        Thanks for the pointer Olli.
        I bought the memory from EBay. You can’t 100% trust everything you buy from EBay :-) So I ran the built in memory test in Windows 10. It rebooted the machine directly into the test. It ran for about 3 hours and reported no errors.
        So far everything seems to work fine.

    • damien says:

      FYI, spoke to an engineer an Intel. If you update to the latest bios (believe it’s 42) you’ll get roughly 2.2GB each way with the Samsung 950, BUT it has to be updated through recovery (not .exe or F7) or you won’t get the improvement.

      • Hi!

        I tried updating to latest bios (0042, which should have been the answer to everything ;-P ), using recovery mode (jumper extraction and all) to no avail. I even went to downgrade to bios 0039 so that I could go again to 0042 (always with recovery mode), but that didn’t work either. I still only get 1.6 GB/s from my Samsung 950 Pro nvme device :-(

        I also tried removing the aditional SATA device I have (Samsung 850 Pro), and even disabling it on the bios, in case it was competing for bandwidth somehow, again no sign of improvement.

        On the bright side, I’m now quite proficient at both bios recovery and opening and closing the case ;-)

        Any chance you can contact that engineer again to ask for more details?

        Thanks in advance!

  11. Superpicsou says:

    I use this NUC as a mediacenter on my TV and i think the Fan is a bit too noisy. Even when i lower the speed to 20% i can still hear it.
    I don’t know if i can lower the speed again. When i’m watching a h265 movie, the proc temp goes arround 65/70°C

    During the setup i had the usb problem with windows 7. I tried to patch my iso with “Windows 7* USB 3.0 Creator Utility” but the process always crashed at one point. So i had to install windows 10 directly. But the damn think doesn’t want my Windows 7 CD Key.

    I think i’ll have to formate again and try installing windows 7 to update it to windows 10 so he accepte my windows 7 licence.

    • Superpicsou says:

      My bad. I wasn’t the Nuc who was making so much noise, but my 2,53 HDD… I didn’t know a hard drive could be so loud.
      We i dont use it for half an our he goes into sleep mode and then it becomes so quiet.
      Now i need to buy SD

      • nucblognet says:

        Haha, good to hear you found the issue! Not all 2.5″ drives are that noisy though. Anyhow, I recommend an SSD always over a HDD…

  12. Jo says:


    Intel’s website says its “max 32 GB” and the Tech Spec says it’s only “16 GB maximum total system memory (with 4 Gb memory technology). Refer to Section 2.1.1 on page 37 for information on the total amount of addressable memory.”

    So, how much RAM does it support IRL?

  13. Hiya!

    You say that “When using a fast PCIe-based SSD drive the maximum bandwidth is limited to about 1600 megabytes per second according to Intel.”

    Could you provide me with a link to the source of that? Haven’t been able to find it.

    It’s a bit frustrating, because I got the NUC6i5SYH and the Samsung 950 Pro, expecting the setup to perform at full speed (2.5 GB/s in reads, 1.5 GB/s in writes), since the requirements are apparently met (PCI Express 3.0 4x). What I get is the aforementioned 1600 MB/s. :-(

    Thanks a bunch!

  14. birinci says:

    Thanks for the review, it’s been of great help… I recently bought my nuc6i5syk, however I can’t get 4K on my TV somehow – it shows 1080p max. I’m using a DP to HDMI cable and the TV HDMI port is 60Hz.

    Also the screen randomly freezez and goes blank (with whatever color the cursor is pointing when it froze – quite weird). Only hard reset brings it back… Has anyone faced a similar issue?

    • birinci says:

      I just read your review on DP->HDMI2.0 adapter review. Apparently the cable I have doesn’t support HDMI 2.0 (i.e. 60Hz).

      I’d still appreciate any help on the screen freeze issue though =)

  15. Kubfan says:

    Hi guys, I hope you are all OK,

    I have a question about the audio 3.5 mm jack.

    Did anyone use Ubuntu / Kubuntu on this NUC, connecting simple 2.0 speakers through the 3.5 jack? Does it work ok?

    The set I think about is to provide the video signal to a TV via the HDMI port but the audio will be provided to 2.0 speakers via 3.5 mm jack, using Kubuntu as OS. I do prefer to have a better sound quality in the speakers, instead of using TV speakers. I hope Pulseaudio will work OK with this configuration.

    Thanks in advance!!


    • birinci says:

      Hi Kubfan,

      I tried what you said and it works – except that it makes a buzzing sound on turn on/off.

      I still havent tried plugging the speakers to the TV instead of NUC. That should work too and maybe it won’t make that noise – also would look cleaner =)

      – Murat

  16. Greg Larden says:


    Just built a nuc6i5syk , with Samsung Pro 950 m.2 pcei and Kingston HyperX Impact 16g DDR4 2400 (only ram in stock anywhere in my area :( but it’s recognized at the units max and runs fine. They actually gave me a better price than the 2333 set of ram because it’s on backorder :) )

    I am very please with performance but have a question on temp. My unit seems to run pretty warm.

    Maximum Performance, Balanced bios setting it idles in the high 30’s low 40’s range.
    If I browse the internet or watch a you tube video it jumps to the mid 60’s low 70’s
    Fan is always spinning at 3000-3200 rpm never slows down even at rest.

    Maximum Performance, Quiet Bios Settings idle is about the same but browsing or youtube gets it up to the mid
    70’s and climbing. Fan spin at 3000-3200 rpm.

    Maximum Performance, Custom settings starting with Quiet settings but fan set to 25% Idles in the 40’s and quickly climbs to high 70’s low 80’s.

    I have been on a laptop for several years so I’m kind of out of touch with cpu performance and temps.

    Are these typical temps for these units?

    Any info would be greatly appreciated.

  17. Michael says:

    Go to balanced performance.
    I was running maximum performance initially, but it was heating up too much. It makes no sense to be running the processor at 100% at all times.

    • Greg Larden says:

      Hi Micheal,

      So Monday was my first full day of development using the NUC. I noticed after about 5 hrs that the cpu was running at 80-90c and the fan never went over 3500. I quickly rebooted and dropped it to balanced, fan stayed at 3200 but was in the low 60’s for the next 4 hrs.

      I was very impressed with the performance on Maximum, on Balance I was satisfied just not impressed with the performance on balanced.

      • Michael says:

        Well running both cores @ 2.7ghz minimum at all times is impressive, but I think it goes beyond the intent of a NUC. If only, right? haha

  18. merki says:


    just bought my NUC6i5SYH 3 weeks ago.
    I wanted to use it as a HTPC/Plex Server wich worked fine I was totally happy with the nuc.
    But then all of a sudden after 2 weeks Fatal Hardware error unable to start an OS. I tried every way.
    It is shipped in now to Intel for replacement. After I searched the web for my problem I found out that a lot of people had the same problem with their 6th generation nuc. Hopefully this was just the first charge Intel send out and I prey my replacement will last longer ;)

  19. Greg Larden says:

    I went thru 2 nuc6i5syk ,first one bad motherboard or something, second was fine for about a week then starting hitting 100 + and fan wouldn’t come on. This happened 3 times in 4 days, I promptly returned it and built a mini-itx with an i5 6500, dd4 2333 ram and the same harddrive.

    The nuc unit is not cheap here in Canada, for what it costs I was very disappointed. Some have had great success with the skylake nucs just not me.

  20. Stereophonic says:

    Hi, I just got my NUC6i5SYH today. I’m using a Samsung 950 Pro m.2 and 32GB Kensington RAM. I tried several times to install Ubuntu 15.10. Unfortunately, I cannot boot. Since I’m not a Linux expert, maybe someone here can tell me how to setup the BIOS to enable boot?

    • Hi, Stereophonic.
      Browse through the BIOS settings and make sure that the M.2 bay is enabled for booting.

      BTW, I could install Fedora 23 withouth a hassle.

      ArchLinux, my favourite distro these days, works nicely as well, although it is not for the faint of heart ;-)

      Hope that it helps!

      Happy hacking,

      • Stereophonic says:

        Hi Pancho,

        thank you for your reply! It is so weird. I see my M.2 SSD as boot device and I selected UEFI. Legacy is disabled. I can install Ubuntu 15.10, but I cannt boot. So I tried Linux Mint 17.3. Boom, installed and it boots… Then I installed the current beta of Ubuntu 16.04. It also boots, however, it hangs and freezes. Ok, it’s a beta. The only thing I don’t understand is why 15.10 does not boot… Maybe I will try one of the other distros you mentioned.

        Best regards,

  21. Kubfan says:

    Hi Stereophonic and rest of mates,

    I have read that Ubuntu 15.10 experiences difficulties when installing it on m.2 SSD drives. But as updates are coming often, this could not be the case any more.

    I have installed successfully Kubuntu 15.10 on NUC6i5SYH using a 2.5” SSD drive, and I used the following guide:

    Please find the partition table I created during the install:

    /dev/sda1 200 MiB in /boot/efi
    /dev/sda2 12000 MiB in /
    /dev/sda3 Resting MiB in /home

    You can select the size of / and /home depending on your needs. But I think the key point, as the guide says, is /dev/sda1 200 MiB in /boot/efi. After I did this and restarted, NUC detected the internal SSD as boot device, so I switched off Legacy and it all worked well. The command:

    [ -d /sys/firmware/efi ] && echo “EFI boot on HDD” || echo “Legacy boot on HDD”

    informed the boot was done through EFI mode.

    I hope this helps.


  22. Stereophonic says:

    Hi guys! Thank you very much for your comments. After a bit (actually a large bit :-) ) of reading, I decided to try Arch Linux on my NUC. Now I have a question regarding the partitioning, in particular about swap. As I wrote above, I have 32GB of RAM, so what size would your recommend for swap? What about hibernation? Is it worth to spend more than 32GB just to enable hibernation?

    Kind regards,

    • Hi!
      It may be too late now, but just in case:
      I don’t think that hibernating will be very useful for a nuc. Suspend to ram at most.
      Hence, you could do nicely with just a couple of gigs of swap.

      My 2c.


  23. Rich says:

    Hey is the CPU soldered onto the board…? I wonder if its possible to replace i5 with an i7?

  24. Julfur says:

    I just bought a nuc6i5syh and I find it a bit noisy on my desk (~3000 RPM).
    I tried to switch to a quiet profile in the BIOS but that didn’t change anything, still ~3000 RPM.

    I dont see any specific settings to lower fan speed, could you explain how did you lower the fan speed by 20/25% please ?

    Thanks, best regards.

  25. In case anybody is waiting for the akasa newton s6 to be available (fanless chassis for nuc6), don’t hold your breath:

  26. A. Falc says:

    Did anybody try Fedora 24 with a Skylake Nuc?

  27. Gary Barnet says:

    Have had a 6i5 NUC for a while now and just got a Samsung PM961 1TB NVME M.2 for cheap ($335 Australian).
    Problem was that I had trouble getting it to work at full speed and Samsung’s Magician software did not help at all The only thing it was really good at was telling me that it was not running as fast as it should have been..
    So a lot of hairpulling and regret to begin with, then research and reading ensued.
    Lots of articles and explainations of how things can go wrong and right, so be careful and make sure you have everything backed up (BIOS, windows, files, et cetera) before attempting these steps below.
    Also beware that doing a BIOS update incorrectly has the potential to brick the NUC (example – if for some reason the power supply stops during the BIOS update, it may brick it and never work again)
    Several hours later I found all the info I needed and got it to work.
    I will list what I did here for others to save them some time.

    1/ update BIOS to ar least version 44 or better using the BIOS recovery method only – otherwise the M.2 speed will not improve. This update allows the M.2 to run at full speed (in my case over 3000MB/s) up from the standard 1600MB/s setting it was locked into originally. I also used 3000VA UPS (Uninterupted Power Supply borrowed at work) with the NUC to prevent any chance of a power supply problem.

    2/ Load the NVME driver for the appropriate operating system from this Microsoft page – .This is the best driver version for the OEM PM961 that I could find, especially since Samsung Magician software does not detect the PM961 as a Samsung drive and restricts the software’s functionality.

    Well this is what I found, if you had a different experience with Magician or anything else, please leave a comment, thanks.

  28. SHQ says:

    Hi Olli,
    Thanks for the detailed review. What are your thoughts on using a VPN such as Ivacy with smart tv boxes? Is it a good idea?

  29. Grasho says:

    After disabling secure boot Peppermint OS Devuan Daedalus installs without issues on the NUC 6i5 SYK and runs smooth as a multimedia machine.
    I would like to upgrade to 2x 8gb RAM. Is the Crucial DDR4-3200 SODIMM compatible with this NUC?

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