While OWC has made enclosures that could pair with Mac mini’s for a long time, the OWC miniStack STX is the first that brings a Thunderbolt hub into the mix, making it an ideal storage and working drive solution for creatives.
Even though Apple just released the new Mac Studio, we at PetaPixel believe that most photographers are going to be best served by the M1-powered Mac mini that was released last year. It’s the best Mac for photographers, especially considering how affordable it is. But it doesn’t have everything a photographer might need, and that’s where the miniStack STX comes in.
Contrary to most new products released by Apple, the OWC miniStack STX is designed to be customized and upgraded as users’ needs change over time. The miniStack STX features a universal SATA HDD/SSD bay and an NVMe M.2 PCIe SSD slot that is easy to access for upgrades and maintenance, three Thunderbolt (USB-C) ports (four if you count the one needed to connect to the Mac mini) for device connections such as keyboards, hard drives, card readers, displays, A/V mixers, cameras, and tablets. The device itself is available for $299 for the empty enclosure or it can be customized at the time of purchase with up to 8TB of SSD storage and 18TB of HDD storage.
Design and Build Quality
The miniStack STX features the same rounded aluminum design dimensions of a current-generation M1 Mac mini and is meant to be a stackable base upon which you can set it on. The device comes in a similar minimalistic appearance as the Mac mini, but with a sleek black finish.
The front of the enclosure features two small lights on the bottom right of the device that are indicators for the two internal drives (SSD and SATA) and a large OWC logo that lights up in Blue when the miniStack STX is powered up. This large illuminated logo shifts to white when the Mac mini is shut down instead of turning off, which I found strange. Why this light stays on at all seems a bit odd to me, but that is a minor design issue when you consider the overall benefits provided by the device as a whole.
While the front and sides of the device are rather minimal, the rear of the enclosure is where you will will find the four USB-C (Thunderbolt) ports for connectivity expansion of the Mac. At a glance, you may also think the device has some USB-A connections as well but alas, that slot is simply for the exhaust. In between the Thunderbolt ports and the exhaust, users will find the 20V DC power connection.
The company claims that users can add a mix of up to five Thunderbolt devices, three USB devices, and two monitors with the miniStack STX depending on the host device. For example with my M1 Mac Mini, I had a XP-Pen Display tablet connected to the HDMI port, a monitor connected to the USB-C on the Mac Mini, a Loupedeck CT and Memory Card reader connected to the USB-A ports, and then through the miniStack STX I had my iPhone, Apple Watch, and Raid storage connected.
Effectively, the miniStack STX replaced my previous “solution” which was a rat’s nest of a USB-hub that sat behind everything on my desk.
The inside of the device is almost as minimalistic as the exterior and features a small motherboard with the SSD, SATA, and port connections. All of this is seated snugly against the cooling fan and exhaust ports. As I mentioned above, the miniStack STX can house a 2.5 inch or 3.5 inch hard drive (up to 18TB in size) as well as an M.2 SSD that can handle up to 8TB.
While it is designed to look nice with the Mac mini, I should mention that it doesn’t require one. The miniStack STX can work with any Thunderbolt compatible device like an iMac, Macbook Pro, PC, Chromebook, and even Android tablets. Actually, it is possible to connect and power some devices including a MacBook Air over the 60W thunderbolt port (the one closest to the power supply) adding even more versatility and use cases for the device at home. That said, it still just looks the best when paired with a Mac mini due to how perfectly it matches its size and shape.
Using a beefier MacBook Pro with this power supply will keep the device running, but it will also very slowly lose power even when plugged since it can’t output enough power. Over the course of three hours of normal work on my MacBook Pro which was plugged into and powered by the miniStack STX, I saw between 2% and 5% per hour power drain.
It is also worth noting that even while heavily stress testing the drives in the miniStack STX and the cooling fan running in high gear, the system is still nearly silent.
Speed and Performance
The company claims the miniStack STX can run at 770 MB/s of “real” performance through the SSD drive and my own testing can confirm those numbers are pretty accurate. This means even if the drives connected inside of the miniStack STX are capable of faster performance, due to the limitations of the Thunderbolt PCI-E channel allocations, the max read/write speeds will be limited to about 770 MB/s. It would be amazing to be able to get peak performance out of the drives installed, but the 770 MB/s speeds are still more than enough for the kinds of work photographers and even many videographers are doing.
As a comparison (and for clarity), the speed performance when working directly off of the SSD in an M1 Mac mini is significantly faster:
Through some further testing, I connected an old WD Green drive to the HDD connection and was able to get about 150 MB/s performance out of it. Not amazing, but still impressive since it managed to breathe new life into an old unused backup drive.
Through the course my testing, I used the miniStack STX SSD to store and edit about 40 GB worth of photos for a client and set up the 5TB HDD as a Time Machine backup for both the 1TB internal Mac mini SSD, and the 2TB miniStack SSD drives.
While the HDD was (expectedly) slow, the SSD was impressively fast via the Thunderbolt connection and I was able to edit my files including some drone video clips without any issue.
Makes An Already Great M1 Mac mini Even better
Storage for Apple devices can be very expensive. For example, going from a 256GB SSD to a 1TB SSD on the M1 Mac mini adds $400 to the base price of the machine. Since the OWC miniStack STX sells for $299 on its own and most fast 1TB SSDS cost just around $100, the cost balances out with benefits. With the M1 Mac mini, whatever size drive you choose is what you are stuck with until the computer dies. With the miniStack STX, you can expand that storage out to 26TB which massively dwarfs the computer’s base storage options all while also gaining the additional ports for expanded connectivity.
Considering how small the Mac mini already is, stacking mine on top of the miniStack STX still let me easily fit it under my laptop stand, set it, and forget it.
Are There Alternatives?
While I was not able to find any devices exactly the same in features as the miniStack STX, there are alternatives solutions for users seeking more storage or more port expansions for their Mac mini (and other devices). This includes the standard OWC miniStack which offers up to 18TB of storage and 208 MB/s performance starting at $85 for the base enclosure. If you’re just interested in the Thunderbolt dock aspect of the miniStack STX, once again OWC has you covered with the $179 Thunderbolt Hub that features four Thunderbolt ports and one USB-A port, or the $279 Thunderbolt Dock that includes 11 ports (four Thunderbolt, three USB-A, one USB-2, one 3.5mm audio, gigabit ethernet, and an SD card reader).
Another great option is the Trebleet Mac Mini Thunderbolt 3 dock, which offers an SD and CFexpress reader in addition USB ports on the front. It also has Thunderbolt 3 connectivity. Some notable differences are that it supports 2.5-inch SATA drives, not 3.5-inch and it has fewer Thunderbolt ports.
Should You Buy It?
If you need expanded and upgradable storage space that is faster than a standard external HDD that is also daisy-chainable and neatly pairs with the Mac mini then, yes, the miniStack STX is absolutely worth every penny.
Update 3/28: We became aware of the Trebleet Mac Mini Thunderbolt 3 dock that offers many of the same features as the OWC miniStack STX and have added it as a viable alternative.