Mac mini M4 on an aluminum dock stand with monitor and peripherals - complete storage setup guide UK

Mac Mini M4 Complete Storage Setup: What to Buy and How to Set It Up

02 Jun, 2026
Posted by: Marian Bohacek

The Mac mini M4 is an exceptional machine. Apple silicon performance, a tiny footprint, and a price that finally makes sense — it's the best value Mac Apple has made in years. There's one catch that catches a lot of buyers off guard: the internal SSD is soldered to the logic board. You can't upgrade it after purchase, which means whatever storage you chose at the Apple Store is what you're living with.

If you went with 256GB or 512GB to keep the upfront cost down, you'll feel the squeeze sooner than you think. macOS alone takes up a significant chunk, and once you add applications, projects, and media, you're managing storage anxiety instead of getting work done.

The good news is there are two very good solutions — and depending on how you work, you might want both.

Option 1: The Acasis Dock — Internal NVMe Expansion Without Opening Anything

The Acasis Mac mini M4 Workstation Dock is the cleverest storage solution for the M4 Mac mini, and the one we'd recommend first. It's a purpose-built aluminum stand that your Mac mini sits on top of — matching the Mac mini's aesthetic exactly — with an M.2 NVMe slot built into the base, dual 4K HDMI outputs, USB-A ports, and active cooling all built in.

The result is a Mac mini that looks like a single, tidy unit on your desk, with up to 8TB of fast NVMe storage added underneath it, two extra HDMI display outputs, and a cluster of USB-A ports for peripherals. All powered by the included 30W PD adapter. One product does the work of three.

The NVMe slot supports M.2 2280 drives at up to 40Gb/s — fast enough for video editing scratch disks, large photo libraries, project archives, or anything else you want off the internal SSD. The SSD is not included, so you choose the capacity and brand that fits your budget and use case.

What SSD to put in it: The Samsung 990 Pro M.2 NVMe is the strongest pairing. PCIe 4.0, up to 7450 MB/s sequential read (though the dock's 40Gb/s interface caps real-world throughput at around 4900 MB/s — still exceptional), 5-year Samsung warranty, and available in 1TB, 2TB, and 4TB. It runs cool, it's proven, and it'll outlast the Mac mini.

Other things worth knowing about the Acasis dock:

The temperature-controlled fan is quiet — it only spins up when needed, and is designed for near-silent operation under normal use.
The dual HDMI outputs support 4K@60Hz each — mirror or extend, your choice. If you currently only have one display connected to the Mac mini's HDMI port, this immediately gives you a second screen without needing a separate adapter.
The internal shielding is designed to avoid interfering with the Mac mini's Wi-Fi antenna — an important detail that cheaper generic stands often miss.
Installation is straightforward: slide in your M.2 SSD, secure with the included screw and thermal pad, connect the custom Mac mini cable, and you're done.

At £125 for the dock plus the cost of your chosen SSD, this is genuinely the best value storage expansion for the Mac mini M4. You're not just adding storage — you're turning it into a proper workstation hub.

Option 2: Fast External SSD — More Flexibility, Works Anywhere

If you want storage that moves with you — between the Mac mini at home, a MacBook at the office, a client's location — a fast external SSD is the answer. The Mac mini M4 has two USB-C ports with Thunderbolt 4 and two USB-A ports on the back, plus additional Thunderbolt ports on the M4 Pro model, so you have plenty of connection options.

For Most Users: OWC Envoy Pro FX

The OWC Envoy Pro FX connects via Thunderbolt 3/USB-C, hits up to 2800 MB/s, is IP67 rated, and bus-powered — no wall adapter, no faff. Available in 480GB to 4TB with a 3-year OWC warranty. Plug it into the back of the Mac mini and it'll sit quietly there permanently, or throw it in a bag when you need it elsewhere. Either works.

For Maximum Speed: OWC Express 1M2 USB4

The Mac mini M4 supports USB4, which means you can get the full 3151 MB/s out of the OWC Express 1M2 USB4. This is the fastest bus-powered portable drive available — faster than the internal SSD in many workflows — and available up to 8TB. If you're running large media projects directly from external storage, this is the drive that won't make you feel like you're compromising.

The Full Setup: Dock + External SSD

For most Mac mini M4 owners who are serious about storage, the ideal setup is both: the Acasis dock with a large NVMe SSD underneath (2TB or 4TB Samsung 990 Pro) for your working files, project libraries, and permanent storage expansion — and the Envoy Pro FX or Express 1M2 USB4 for active projects, portability, or backup.

This gives you a clean desk, a proper dual-monitor workstation setup, plenty of peripheral ports, and fast storage in two tiers. The internal 256GB or 512GB SSD handles macOS and applications. The dock NVMe handles your library. The external SSD handles whatever you're actively working on or need to take with you.

It's a proper setup — not a workaround.

What Capacity to Buy

A quick guide based on what you actually do:

General use, documents, photos: 1TB NVMe in the dock is plenty. Pair with a 1TB external if needed for backups.
Video editing (1080p–4K): 2TB in the dock, plus a 2TB external SSD for active projects.
Photography (large Lightroom/Capture One libraries): 4TB in the dock. These libraries grow faster than you expect.
Music production, 3D, or heavy creative work: 2–4TB in the dock plus a fast external for scratch disks and exports.

Free Shipping to the UK and Ireland

Everything on this page ships free to the UK in approximately 2 working days. Orders to Ireland over £100 include free shipping too. If you want help working out the right combination for your specific setup, drop us a message — we're happy to advise before you buy.