Intel NUC6i5SYH Mini PC Review

The casing follows the design of previous NUC cases with a plastic top and bottom and a single-piece milled aluminium housing. Previous NUCs have been susceptible to scratches on the shiny top cover and we don't see any reason to think that this NUC is different. A range of replacement and alternative lids are available though.

Four screws in the rubber feet allow the base of the unit to be easily removed for access to 2 DDR4 SO-DIMM slots that can take a maximum of 32 GB. There's an M.2 slot supporting PCIe SSDs in 2280 or 2242 format. There's a 2.5 inch SATA housing in the base which can take up to a 9.5 mm height drive so there's plenty of options on storage.

Externally we see a good range of ports. Both HDMI 1.4a (for 4K up to 30 fps) and Mini DisplayPort 1.2 (4K up to 60 fps) are included along with 4 USB 3.0 ports, a GB LAN port (Intel Pro 1000) an SD card reader (SDXC) a headset port and the power port. There's no consumer IR port on this but there's an internal header for NFC. You'll also find a security lock slot on the side, a power button and power-on LED. 

There's a fan inside the NUC6i5SYH that we'll talk more about later.

Finally there's a VESA mounting plate for easy mounting onto the back of monitors. 

Confirming an NVMe SSD are the highs disk transfer speeds in the sequential read tests shown below. 4K block read and write speeds are good too so there's potential here for working with large files. For example, 4K video files. In a test of the SD card reader we were able to achieve over 80 MB/s sequential read speed from a Lexar Pro SDXC UHS 3 16 GB card. Sequential write speeds were just over 40 MB/s. (Using Crystal DiskMark.)

An interesting feature of the Skylake integrated graphics unit is the video processing engine which can perform video optimisation, adjustments and can render between various formats. For video hobbyists and YouTube producers it can provide a very significant speed-up compared to CPU-only performance and as long as the edit doesn't include too many graphics intensive filters and particles it can be faster than discreet mobile graphics cards. This reviewer has tested many platforms over the last 6 months using PowerDirector and a fixed set of rendering files. (Video of a 3-way rendering test including the Surface Book here.) The slowest test result recorded so far was with a Surface Pro 3 under warm conditions where the rendering process can be as long at 14 minutes. Recent Core m5 and Core m7 platforms tend to take about 10 minutes and the Surface Book (without discreet GPU) took 6 minutes and 40 seconds. None of these platforms use the Iris Graphics solution. The Intel NUC6i5SYH with the Core i5 6260U with Iris Graphics 540 took a maximum of 4 minutes and 18 seconds and a minimum of just 4 minutes to perform the same test. A test with a Haswell generation (2014/2015) quad core CPU with Intel Iris Pro graphics (Core i7 4750 HQ with Intel Iris Pro 5200) showed an interesting result. This GPU has only 40 EUs (vs 48 in this NUC) but can clock up to 1300 Mhz (vs 1050 Mhz on this NUC.) The rendering performance was 5% faster. 

If you're editing with a lot of fades, overlays, text and effects the advantage of Intel Quick Sync reduces and there's a cut-off point where CPU cores and discreet GPUs are fast but for home video and YouTubers quick-sync generally does the best job as long as the video editing software includes Intel Quick Sync support.

Temperature isn't an issue on this standalone mini PC despite significant warmth being felt at the exhaust ports under load. More important is the effect that the temperatures have on Turbo Boost.

Using prime95 and Furmark we loaded the unit to see the effects on CPU clock rates.  WHile CPU levels stayed high during a long, 15 minute CPU load test it was a different story when we introduced the GPU load test using Furmark. After just a few minutes the CPU clock rate was at 1.1 Ghz and the GPU had down-clocked to 600 Mhz. (about 55% of maximum.)

In a 3D-only test the performance of the CPU and GPU also reduced after a short while. Throttling is clearly something that gamers will have to consider but it could also affect video rendering performance.

Although there's no dedicated digital audio output on the NUC6i5SYH there are a number of ways to extract digital audio. The HDMI port is one but there are also possibilities to use WiDi/Miracast and Bluetooth audio profiles. Analogue audio was clean over a headphone test. The Realtek audio software includes equalisation adjustment and effect features.

The Intel NUC 6i5SYH with Intel Core i5 6260 and Intel Iris Graphics 540 doesn't look any different to the previous generation NUC 515RYH so it's all down to performance differences with the new model. While the Skylake CPU offers slightly better performance in our tests (5-10%) it's the GPU that's the biggest attraction. It offers a good range of PC gaming entertainment and impressive video rendering and conversion speed. We haven't tested a CAD or graphic design program but given the maximum 32 GB RAM there's definitely scope for some creativity here. Photographers will like the fast SD card slot and DisplayPort options and the PCIe SSD port allows the fastest speeds possible with a single SSD. Use the additional 2.5-inch SATA drive for video and photo storage and you've got quite the flexible workstation. 

The Intel NUC remains an interesting and flexible mini PC for those looking for something that is tweakable, portable and cute and our build of this Core i5 version offers some of the best performance you can expect. It's the perfect dorm-room PC and a neat, tidy and energy efficient office PC.

There's no consumer Infra Red port on the front of this NUC but then again it's not really targeted at the home theatre market. Those of you thinking about HEVC and 10-bit H.264 playback might want to take a closer look at the options to build a dedicated IR receiver lid though.

Heat isn't an issue and noise will only be a problem at under 1 meter although moving the unit further away than arms length reduces its ability to be an easy SD card and USB accessory hub. 

We haven't tested Linux on the Intel NUC 6i5SYH but BIOS options allow legacy booting. Support for the new GPU is probably the major issue with a Linux build.

Pricing is difficult to comment on given the wide range of options. A single 2GB RAM module and a boot-from-USB OS is the entry-level configuration but most will probably be looking to take advantage of the PCIe SSD interface and at least 8GB of RAM.  The Samsung SSD we're using here is a $200 module. Add the 8 GB of DDR4 and a Windows 10 license and you're looking at $350 on top of the $350 basic cost. At this level it gets difficult to justify a desktop unit with a non-upgradeable 2-core CPU and integrated graphics although it would be difficult to find something that competes on overall performance in this small size.

The Intel NUC remains an interesting and flexible mini PC for those looking for something that is tweakable, portable and cute and our build of this Core i5 version offers some of the best performance you can expect. It's the perfect dorm-room PC and a neat, tidy and energy efficient office PC.

Note: This review was written while using the NUC6i5SYH and no stability or performance issues were seen.