A Console-Size Mini-ITX Option

A small form-factor crowdfunded mini-ITX case

Examining the lower limits of enclosure volume has become something of a cottage industry in the last few years, with crowdfunded projects such as the NCASE M1 and the DAN Cases A4-SFX providing backers with custom designs that attempt to reduce the mini-ITX computer case concept to its absolute minimum size. The Sentry 2.0 differs in a few ways from those previous efforts, most obviously in that it is not a “shoebox” design, opting instead for a narrow game console-style layout. It is also a steel enclosure rather than the all-aluminum designs from DAN Cases and NCASE (both produced by Lian Li), making it quite a bit heavier while promising a more rugged construction.

“Sentry is the world's first truly console-sized gaming PC chassis. It houses powerful components within a volume below 7 litres, which over the decades has been considered the optimal size for all media appliances residing in front of a TV. Sentry 2.0 is an evolution of Sentry, bringing more features and more performance in the same sub-7 litre package.”

The Sentry 2.0 is the follow up to the crowdfunded original Sentry case, both of which are game console-sized mini-ITX enclosures that are designed to house standard components within the limits of a 6.9-liter total volume. Unusually we are reviewing this case during its crowdfunding campaign – though it has actually been fully funded at this point and you can check out the page on Indigogo here. Pricing is similar to what we have seen from other crowdfunded cases, and while $260 might seem high (especially for a steel case rather than aluminum) there has been quite a bit of thought packed into the Sentry 2.0 design.

In addition to supporting mini-ITX motherboards the Sentry 2.0 makes use of SFX form-factor power supplies and can support a full-length graphics card if you are air-cooling the CPU (the extra space beyond an ITX-sized GPU could then support a 120mm radiator and slim fan). It’s a pretty straightforward internal layout, so without further preamble let’s check out the design and then move on to the build I came up with for this pre-production Sentry 2.0, which DR ZĄBER was kind enough to send to us.

First, however, a look at the specifications:

  • Main body dimensions (WxDxH): 340 x 310 x 66mm, 6.9L
  • Motherboard format: Mini-ITX
  • Power supply support: SFX 100mm (SFX-L not supported)
  • Expansion slots: 2, full height, ATX reference PCB width
  • Drives:
    • Main drive installation mounts:
    • 1 x 2.5" partially above motherboard
    • 1 x 2.5" next to SFX power supply
    • Secondary drive installation mounts:
    • 2 x 3.5" inside VGA bay
  • Memory Compatibility:
    • Standard profile DIMM modules
    • Max 31.4mm tall pcb/34mm with heatspreaders
    • Tall modules will obstruct 2.5" drive bracket
  • VGA Card Compatibility:
    • Full Length GPU for use without AIO Liquid Cooling or 3.5" HDDs
    • ITX-sized GPU for use with AIO Liquid Cooling or single 3.5" HDD
  • CPU cooler support:
    • CPU Socket far from PCI-E Slot:
      • Max height of 47mm (standard intel box cooler height)
      • 120mm All-In-One Liquid Cooler, radiator + fan max height of 50mm
    • CPU Socket near the PCI-E Slot:
      • Max height of 47mm and primary 2.5" mount obstructed
      • Max height of 37mm and primary 2.5" mount available
  • Front ports: 2 x USB 3.0
  • PCI-E 16X Riser: high-quality shielded 50mm ribbon
  • Material: 1mm galvanized steel with structural powder coating
  • Security: Kensington slot

Pricing and Availability: $260, Indigogo campaign

Packaging and Contents

Case Design

The Sentry 2.0 is currently offered in black and navy gray (a light gray with a bit of a teal cast). This is an all-steel construction with a structural powder-coat finish, and it feels very solid. For these photos I had already attached the included feet, which is a good practice before working on it to protect the finish.

While it can be difficult to discern relative size in a photo without strategic placement of common household items (the Coke can method) I will emphasize that this is a very compact design. It is (rounding to the nearest tenth) 13.4 inches wide, 12.2 inches deep, and 2.6 inches tall.

The case opens easily with a pair of screws on either side, though it bears mention that these are a security type that requires a special driver (included, of course).

Of note is the inset section inside the top case (on the right side in the photo above). In speaking to the Sentry team I find that helps reduce amount space behind the GPU where hot air could accumulate, and it doubles as a safety mechanism (in the horizontal position this will be the top) to mitigate any hot spot directly above the GPU.

In these photos I have installed the front USB ports and power button, but otherwise this is a blank slate as we move on  to the build process.

And now we are free to install a variety of mini-ITX configurations, and one of the surprising things to me about this design is that there really are a number of options.

Installing the System

The latest version of the manual is a must-download before beginning the build process, and for your reference it is available here (PDF). This is, without a doubt, the finest manual for a computer enclosure I've ever seen. Before you dismiss the rest of this review as nonsense based on my apparent mental state in lavishing praise on a digital manual, I have to add that it is so precise and descriptive, and has such detailed illustrations, that it makes what could easily be a frustrating process and makes it as simple as building in a 6.9-liter case can be.

With the manual at hand (a laptop/tablet/phone with the PDF is an essential companion) the build process begins in earnest, and planning is the key here. For example, as the motherboard is attached directly to the floor of the enclosure it is important to install the cooler before mounting it. You may notice that I did not in the image above, and so I was forced to take the motherboard back out (which also involves partially removing the power cable extension which is grounded to the case floor as well, and partially obstructs one corner of the board).

This table of potential build configurations is provided in the manual:

Sentry 2.0 Example Builds
Use-Case Orientation CPU CPU GPU Memory Storage
Living Room Gaming PC Horizontal 65W TDP Air Cooler 47mm 150W Full-Length
Blower Cooler
2 x 8GB DDR4 1x M.2 SSD
2x 2.5" HDD
Living Room HTPC Horizontal 45W TDP Air Cooler 37mm Integrated 2 x 4GB DDR4 1x M.2 SSD
2x 3.5" HDD
Living Room NAS Horizontal 45W TDP Air Cooler 37mm Integrated

2 x 4GB DDR4

1x M.2 SSD
2x 2.5” HDD
2x 3.5" HDD
High-End Gaming PC Vertical 65W TDP Air Cooler 47mm

180W Full-Length
Open-Air Cooler

2 x 16GB DDR4 2x M.2 SSD
2x 2.5" HDD
High-End Workstation Vertical 95W TDP Liquid Cooling 27+20mm 180W ITX-Size
Open Air Cooler
2 x 16GB DDR4 Standard Height 2x M.2 SSD
2x 2.5" SSD
Ultra-Quiet Gaming PC Horizontal 65W TDP Liquid Cooling 27+20mm 120W ITX-Size
Open Air Cooler
2 x 8GB DDR4 Standard Height 1x M.2 SSD
1x 2.5" HDD
Ultra-Quiet HTPC Horizontal 45W TDP Liquid Cooling 22+15mm Integrated 2 x 4GB DDR4 Standard Height 1x M.2 SSD
1x 2.5” HDD
1x 3.5" HDD

For my purposes I went with an air cooler for the CPU (the SilverStone Argon Series AR11) and a full-length GPU, and here is where I got carried away. One of the problems with a job like this is that it is very easy to lose touch with reality when surrounded by high-end components, and so when planning the build I started to think about the most outrageous CPU/GPU combination I could fit inside this tiny enclosure. The result was the (questionable) selection of an Intel Core i9-9900K processor paired with an NVIDIA GeForce RTX 2080 Ti Founders Edition graphics card. I fully admit that this is not a realistic or recommended scenario, as the manual points out:

Like most small form factor cases, Sentry 2.0 has physical limitations affecting thermal performance of cooling components installed inside. The main difference from standard tower cases in this matter is lack of case fans, that would induce airflow exchanging the air heated up by working computer components for fresh cold air from the outside. Because of that, the airflow is induced only by fans of the cooling solutions attached to installed computer components (CPU & GPU).

It is recommended to take note of this limitation as high-end computer components rely greatly on hot air being constantly exhausted from the chassis by case fans, and their cooling solutions are not designed with small form factor cases such as Sentry 2.0 in mind. Installing expensive high-end components like 125W+ TDP CPU or 250W+ TDP GPU might end up bringing diminishing returns on the investment, if their thermal performance is limited by the chassis.

Well there you have it. This case would be very well served with a 65W processor (which would also allow for a quiet fan profile for your CPU cooler), and while I would not put a really hot graphics card in this case the RTX 2080 Ti actually did better than I was expecting – in part due to the volume of air that the Founders Edition expels from the top of the card, which was blowing straight out of the top of the case (in the vertical orientation that the manual recommends for a high-end gaming PC build).

Moving back to the build process, with the motherboard (this time with the CPU cooler pre-installed) in place I moved on to the GPU, and here you have a couple of options for connecting it to the motherboard. A PCB riser is included (two pieces, a right-angle adapter and an extension), and you can also use a flexible PCIe riser cable if you prefer.

The GPU installation is quite easy once this riser is installed along with a metal bracket attached to the center beam that supports it, and this particular GPU fit without any issue and there was still just enough clearance above it for the PCIe power connectors. I will use this part of the install process to demonstrate how detailed the manual is, as it includes diagrams of component sizes and clearance, and in this section it shows exactly what the limits are for a full-length GPU install.

With the GPU in place I installed the small bracket that permits up to two 2.5-inch drives to attach to the space between the GPU and motherboard/PSU, and if you do choose to install two drives they will need (naturally) to have their connectors facing the outside of the case on both sides.

This does create a little more of a complex situation for routing SATA power and data cables, but it can certainly be done. My PSU uses ribbon-style PSU cables, which I generally prefer (though the Sentry team points out that these can actually be harder to use in this case). The PCB riser could interfere somewhat with this PSU's SATA connector for the drive on that side, but this depends on if you are using a connector at the end of a cable (generally thinner) vs. one in the middle. This bears mention as the PCB is very close to the drive's connections, so bear that in mind. Best practice would be to use two SATA cables with a PSU like this one to avoid any issue.

Speaking of the PSU, this must be of the SFX variety (no SFX-L units) and it installs easily to a pair of mounts facing the outside of the enclosure. Here another clever design choice is evident as there are notches that allow your screwdriver easy access – a small thing but appreciated nonetheless (ignore the fact that was using the wrong screws in the photo – I replaced these with the proper 6-32×6 screws recommended in the manual before moving on).

Should you not choose to install a full-length GPU you have more build options, including the use of standard 3.5-inch hard drives. Two of these can be installed in place of the GPU, which provides a total of four drives (with the 2.5-inch drives) – not counting any M.2 storage you may have on the motherboard. Another detailed illustration shows the mounting process for these hard drives:

I appreciate the flexibility in mounting them to the perforated side panel, and while at first it may seem like valuable airflow will be obstructed there would be no system components on that side of the case – and the other side has its own ventilation.

Another other combination that I'll briefly address is that of a short GPU and AiO liquid cooler, which I will have to revisit once I have the requisite slim 120 mm cooler (or standard cooler/slim fan combo).

Such a setup would not only allow for very powerful CPUs to be installed with vastly more effective cooling than even the best 47 mm air cooler can provide, but still permits a short GPU (up to 175 mm) to be installed next to it.

In this example from DR ZĄBER a Corsair AiO unit is installed with a slim 120 mm fan

The finished build with my selected components went together with less effort than I imagined, though I went with one of the simplest possible builds here (air CPU cooler, single SSD).

Clearance was not an issue as the case went back together, in part due to the way I folded the flat PSU cables in my build. While not required, using a PSU with attached cables might actually be a better idea, as is sometimes the case with these ultra-small enclosures as it frees up a bit of space (and this case was designed to route that conventional cable type a little better than these flat cables).

Another aspect of the design that I appreciated was the clever way the base is installed, as this can be mounted with the case fully assembled as it is a tool-free process.

The stand has a pair of rounded screws at either side which are cushioned with rubber washers. To install you simply line these up with the holes on the side of the enclosure and slide them into their locking position. I ended up attaching the stand to the side panel to take this photo, and I appreciated that it was still possible to slide the panel back on without removing the stand (though this requires using the edge of a table as I did).

Replacing the top cover and screwing it into place was effortless since no cables or components presented any clearance issues, and I then set about testing this monstrous build of mine. The result? Better than you might expect, actually!

Thermals were really not an issue beyond the usual struggle to keep a powerful CPU in check under full load with a low-profile air cooler, though the SilverStone model I used (review forthcoming) did an admirable job – though I must repeat that Core i9-9900K + 47 mm air cooler = bad idea. With ambient temps of ~16.7 C I experienced CPU temps of 29 C at idle, rising to a high of 71 C during gaming benchmarks. Not too bad considering this is a 47 mm cooler – but under stress I hit the 100 C mark and while the CPU was not throttling I didn't push it past the 5 minute mark. For its part the RTX 2080 Ti FE was quite manageable, as hot air escaped immediately out of the top of the case (again, positioned vertically for this build), and a high of 79 C after a couple of benchmark runs. Sustained temps would be higher, but a more aggressive fan profile would help offset this.

Conclusion

The Sentry 2.0 is an excellent small form-factor design and its overall presentation and build experience are quite impressive. The build process – while not the easiest in the world in such small quarters – was quite straightforward when following the excellent instructions, which include many images and exact clearance measurements to help guide you during the process.

While I would love to see this offered as a mainstream product at a lower price, the high cost is a reality of its current low-volume production – just 500 units are the initial campaign goal. This sturdy, well realized design offers just about the bare minimum of space to support a truly high-end computer build with standard components, and with mini-ITX motherboards providing fewer compromises than ever (and SFX power supplies supplying ever more power density) it really becomes a question of thermals when you cram this much compute power into such a small space. While $260 is a lot to ask for an enclosure this is a unique and flexible design that won't disappoint.