GMKtec NucBox K16: 30-second review

GMKtec has been on something of a roll lately, churning out mini PCs with genuine gusto. Where some of its stablemates have leaned on older or obscure silicon, the NucBox K16 takes a different approach, reaching for the AMD Ryzen 7 7735HS. This chip has been quietly powering a decent slice of the mini PC market since 2023, and it also made an appearance in some laptops.

The 7735HS is essentially a Rembrandt Refresh, which is a Zen 3+ architecture part built on TSMC's 6nm node. It is not, let us be clear, a cutting-edge processor. AMD has since moved on to Zen 4 and is now very pleased with itself about Zen 5. Yet the 7735HS remains a competent and well-understood chip, and crucially, one that GMKtec has used before in the K2 model.

Here it's connected to 32GB of DDR5 memory, not its fastest possible option, but enough to feed its Radeon 680M GPU, and dual 2.5GbE LAN ports.

The chassis is a step up from the plasticky boxes that characterised this segment not long ago. A CNC-machined aluminium C-frame with a sandblasted anodised finish gives the K16 a premium, almost Zen-like quality on the desk.

As NUCs go, this one is extremely compact, being 107 x 111 x 56 mm and yet packs an astonishing amount of connectivity into its footprint.

The headline connectivity act is the combination of OcuLink and USB4, both of which can be used to attach external graphics. OcuLink, running at 64 Gbps over PCIe 4.0 x4, is the faster of the two and the better choice for an eGPU enclosure. USB4 at 40 Gbps provides a more broadly compatible, if slightly slower, alternative. The dual 2.5 GbE LAN ports and Wi-Fi 6E round out a networking suite that would embarrass many a budget desktop.

The main caveat, and it is a rather substantial one, is the price. At launch, the K16 starts at $679.99 (£541) for the 32 GB + 512 GB configuration, with the 1 TB variant pushing to $729.99. For a machine built on a Zen 3+ platform, that is an assertive number, particularly when newer Ryzen 8000-series mini PCs are circling at similar or occasionally lower prices. Those later designs, like the 8040, have an integrated NPU, which this chip can’t match.

Due to the age of the hardware and the choice to use regular DDR5 rather than LPDDR5X, this design is not among the best mini PC systems we've tested, but it's perfectly serviceable for less demanding roles.

GMKtec NucBox K16: Price and availability

• How much does it cost? From $680/£540/€620
• When is it out? Available now
• Where can you get it? Direct from GMKtec and via online retailers

The K16 is available direct from the GMKtec website, alongside online retailers like Amazon.com and Amazon.co.uk.

There are two configurations available, both with 32 GB of soldered DDR5 RAM. The base model ships with a 512 GB SSD at $679.99, whilst the 1 TB variant commands $729.99. Both launched at a discount from their listed MSRPs of $899.99 and $949.99.

Normally, MSRPs should be ignored, but for those buying via Amazon.com, that’s about the price you are expected to pay, worryingly. UK Amazon.co.uk prices are equally outrageous, starting at £809.96.

Because of this discrepancy, I’d recommend buying directly from GMKtec, and there is another reason for doing this. GMKtec is bundling a 8-in-1 USB Hub Dockign station with every purchase, which is a thoughtful touch..

The increased cost of DDR5 memory is impacting all pre-built systems, altering the competitive landscape. This is impacting new products coming to market, like the K16, that must contend with cheaper units built before the recent price hikes for components.

The Bosgame M4 (see my review here) in a comparable 32 GB + 1 TB configuration was available for around $579.99 at launch. Rival mini PCs based on the Ryzen 7 8845HS, a Zen 4 part with meaningfully superior iGPU performance, hover in a similar or only modestly higher bracket. GMKtec's counter-argument is the premium chassis quality and the OcuLink port, which not every competitor offers at this price point.

However, on Amazon.com, I found the Minisforum UM880, which uses the Ryzen 7 8845HS, 32GB of RAM, and 1TB of storage for just $749, and it also has OCuLink.

As in my previous review of the K13, there are questions here about the cost of this equipment and how the rising cost of memory and storage is distorting the pre-built PC market.

• Value: 3 / 5

GMKtec NucBox K16: Specs

GMKtec NucBox K16: Design

• Premium aluminium chassis
• Dual-fan active cooling
• Easy access

The NucBox K16 marks a notable step forward in build quality from the broader GMKtec catalogue. The CNC-machined aluminium C-frame chassis, finished with a sandblasted anodised treatment, lends the machine a solidity that others lack.

At 4.21 x 4.37 x 2.20 in (107 x 111 x 56 mm), the K16 is compact without veering into the sort of extreme miniaturisation that sacrifices sensible port placement. The front panel is well considered: the OcuLink port and USB4 Type-C sit alongside two USB 3.2 Gen 2 Type-A ports and the 3.5mm audio jack, with the power button tucked neatly at one end. The logic of placing OcuLink at the front is debatable, but it is a cosmetically minor quibble.

The rear panel is rather busier, accommodating dual 2.5 GbE LAN ports, HDMI, DisplayPort, two more USB 3.2 Gen 2 Type-A ports and the DC power input. Hot air exits through the rear vents, which is a tidier thermal arrangement than some competitors that exhaust downwards or sideways across connected cables.

If you didn’t notice, there has been a trade-off here. This machine only has one USB4, with the bandwidth that might have provided another is used for the OCuLink presumably.

Cooling is handled by a dual-fan arrangement with copper heat pipes that’s a more serious thermal solution than the single-fan setups found in cheaper mini PCs. GMKtec has also included three selectable performance modes: Silent at 35W, Balanced at 45W, and Performance at 50W.

These can be toggled via the BIOS or a dedicated utility, which is the kind of user-facing flexibility that working professionals will appreciate when they need to dial back noise during a video call or unleash full performance for a render job.

As with most of GMKtec's recent output, the K16 ships with a VESA mounting bracket, allowing it to be affixed to the rear of a compatible monitor. There is also a Kensington lock slot for environments where the temptation to pocket a small, premium-looking PC might prove too strong for some colleagues.

Access to the inside is extremely easy. The four feet unscrew to release the silver shroud, and then four small screws are revealed that hold a fan bracket in place before you can get to the storage layer.

One of the two M.2 2280 slots is occupied by the provided SSD, leaving the other entirely free. Both slots are PCIe 4.0, enabling up to 7500 MB/s with appropriate drives.

What there isn’t any sign of is the memory, since this is soldered to the other side of the mainboard. That’s one of the disappointments of this design, but in most respects, it's nicely engineered and easy to upgrade.

• Design: 4 / 5

GMKtec NucBox K16: Hardware

• AMD Ryzen 7 7735HS
• 32 GB DDR5 6400 MT/s
• Lacks an NPU

The AMD Ryzen 7 PRO 6850U is a mobile processor featuring eight cores, launched in April 2022 as an offshoot of the Ryzen 6000 series. And, the closest silicon from the core series is the Ryzen 7 6800H, a Zen 3+ (Rembrandt) architecture chip made for Socket FP7.

The AMD Ryzen 7 7735HS requires a little context. It is a mobile processor built on AMD's Zen 3+ architecture, fabricated on TSMC's 6nm process node. It debuted in 2022 as part of the Rembrandt Refresh family, and is in most practical respects extremely close to the Ryzen 7 6800H that preceded it. Eight cores, sixteen threads, a base clock of 3.2 GHz and a boost up to 4.75 GHz, entirely respectable numbers for a mini PC that is not attempting to position itself at the extreme budget end of the market.

The integrated graphics are Radeon 680M, based on the RDNA 2 architecture with 12 Compute Units running up to 2200 MHz. AMD's Radeon 680M is well understood at this point: it is meaningfully ahead of the older Vega-based iGPUs, broadly comparable to a GeForce GTX 1050 Ti in rasterised tasks.

The issue, as I’ll talk about more in the performance section, is the memory chosen and its configuration. Reading the GMKtec promotional material, it talks about LPDDR5 at 6400 MT/s. But this NUC doesn’t have LPDDR5X, it's just a low-power version of DDR5, and that means less memory bandwidth. LPDDR5X offers up to 33% higher data rates (up to 8,533+ MT/s vs 6,400 MT/s), and roughly 24% better power efficiency, but the AMD Ryzen 7 7735HS doesn’t support it.

There is also an issue with the use of memory channels in this design that I’ll discuss in the performance section.

The storage situation is worth examining carefully. The K16 features two M.2 2280 slots, both of which support PCIe 4.0 x4. This is a meaningful specification advantage over mini PCs that top out at PCIe 3.0 on their secondary slot. Combined capacity is rated up to 16 TB with 8 TB per slot, a generous amount even for a creative professional workload.

The default shipped SSD is, however, a PCIe 3.0 drive. This is a slight disconnect: GMKtec has fitted PCIe 4.0-capable slots and then shipped a PCIe 3.0 drive installed, presumably to manage the retail price. Aftermarket upgrades to a PCIe 4.0 NVMe drive are straightforward given the accessible design.

The OcuLink port runs at 64 Gbps via PCIe 4.0 x4, which is the fastest external GPU interface available on a mini PC at this price point. Thunderbolt 4 eGPU connections are limited by the PCIe 3.0 x4 tunnel that Intel imposes; OcuLink sidesteps this entirely. Paired with GMKtec's own AD-GP1 eGPU dock, the K16 can act as a credible light gaming or GPU-compute machine when equipped with a suitable discrete card.

Memory is the one area that gives pause. The 32 GB of LPDDR5 is soldered directly to the motherboard, making it entirely non-upgradeable. For the majority of users, 32 GB will be more than adequate; for those running large language models locally or editing 8K video, it is a ceiling that cannot be raised.

• Hardware: 3.5 / 5

GMKtec NucBox K16: Performance

Logically, the system should be compared to the GMKtec K2, since it uses exactly the same AMD Ryzen 7 7735HS. And, I have reviewed that exact hardware.

Unfortunately, I don’t have that machine to hand, and the data I have from it pre-dates the use of the CineBench24 and GeekBench6. But I will come back to the K2, I promise.

What I did have was recent data from the GMKtec NucBox M7 Ultra, which uses the AMD Ryzen 7 PRO 6850U. That’s a Zen3+ Ryzen 6000 series chip from 2022, whereas the K16 uses a 2023 Ryzen 7000 CPU that also uses the Zen3+ architecture.

As you can see from the numbers, the results are remarkably close, partly because these chips both have the same number of cores/threads, and the Radeon 680M GPU, and these limiting factors.

However, when I tested this system, something didn’t seem right. Because while I didn’t have much comparison data from the older K2, I did have 3DMark scores, and they told an entirely different story.

The Wildlife score on the K2 was 16647, whereas on the K16 it's only 9846. How?

What made this doubly odd was that, because the K16 uses LPDDR5, it should have slightly more bandwidth than the standard DDR5 used in the K2.

Digging back into my review files, I discovered that the K2 had a DDR5 memory arrangement where it used two SODIMMs of DDR5 4800 MHz, and these were 64-bit modules, used by the system as eight 32-bit channels.

So what has the K16 got? Well, it has two 16GB modules at 6400MHz, but disturbingly, these are just 32-bit LPDDR5.

The K2 with two 64-bit modules could effectively run as quad channel, where the K16 is only dual channel, thus the performance discrepancy between them.

If this arrangement had been quad channel, it would have represented roughly a 33% bandwidth increase over DDR5 4800MT/s, but because it’s only dual channel, that’s not the case.

Another interesting aspect of this system, which I discovered in the CPU-Z analysis, is that this CPU can be run with a 50W TDP, and the TDP limit is confirmed at 45W from the CPU-Z data, with PL1, PL2 and PPT all locked at 50W. Therefore, GMKtec has set this unit running at its maximum performance configuration by default.

Another takeaway from the benchmarking is that this machine has M.2 PCIe 4x4 slots, but GMKtec only used a Gen 3x4 drive, which lowered performance.

Despite these points, for general productivity such as office applications, web browsing, video conferencing, and code compilation, the K16 will feel snappy and capable. The 32 GB of RAM, even in its soldered form, is generous enough to support heavy multitasking without complaint.

Light gaming at 1080p on older titles or less-demanding current games is entirely achievable with the 680M; do not expect to push anything particularly modern at high settings without using that OcuLink port.

The three performance modes are a useful feature. Silent mode at 35W keeps the fans barely audible whilst still delivering perfectly adequate desktop performance. The full 50W mode delivers tangible improvements for sustained workloads, but at the cost of more noticeable fan noise. Balanced mode at 45W will be the sensible default for most users.

For those curious, all my benchmarks were done in Performance mode to show you what the best possible numbers look like.

While not poor, the results from the K16 reveal yet another mini PC that never reached its full potential due to some creative choices made by the makers.

• Performance: 3.5 / 5

GMKtec NucBox K16: Final verdict

The GMKtec NucBox K16 is a machine that rewards scrutiny, though not always in the ways its marketing materials might suggest.

On paper, the specification reads impressively: a capable Ryzen 7 7735HS, 32 GB of fast memory, dual PCIe 4.0 M.2 slots, OcuLink, USB4, and dual 2.5 GbE LAN in a premium CNC aluminium chassis. In practice, the way the memory is organised and the use of a PCIe 3.0 SSD don’t make the most of this Ryzen platform.

What the data also confirms is that GMKtec has set the K16's power limits aggressively, with PL1, PL2 and PPT all fixed at 50W. There are no conservative defaults to contend with here; instead, this machine ships running flat out, which will flatter benchmark results whilst also keeping the fans busier than a more gently tuned configuration might.

None of this makes the K16 a bad machine. The connectivity story remains excellent, OcuLink is still a class-leading feature at this price point, and the build quality is genuinely above average for the segment. But the memory specification warrants a footnote in any purchasing decision, particularly at a price point where honesty in the small print matters.

The biggest issue here is undoubtedly the price, and that might be something we’ll need to accept given the huge hole in memory and storage supplies AI has created. But with so many alternatives in the channel made before memory became stupidly expensive, new designs like the K16 might find the competitive market even more of a problem than it typically is.

Should I buy a GMKtec NucBox K16?

Buy it if...

Don't buy it if...

Also consider