Adding Internal Storage to a Dell Wyse 3040


September 5, 2023

Mods Reviews
3040 storage thin client Wyse



We’ve previously covered the Dell Wyse 3040, a compact yet versatile thin client which we are rather fond of. We’ve installed Linux on it, as well as comparing it to the Raspberry Pi 4.

It’s not without its issues though, one of which is the limited internal storage.

The 8/16GB of internal storage is fine when used as a thin client. It’s less fine if you want to run a proper OS on it. And it’s simply not enough if you want to run a fully fledged GUI-based OS with a basic set of applications.

A user by the name of April shared a PCB design with the ParkyTowers site, which allows additional internal storage to be added to the 3040, without requiring modifications to the motherboard.

We decided to take a look at this board, and check it out for ourselves. This article will show you how to do this to your 3040, while documenting our experience of using it.

You can also check out our accompanying video, which looks at the same process outlined in this article.

Internal M.2 Slot

The Wyse 3040 doesn’t have any SATA ports, but what it does have is an M.2 slot.

Before you get your hopes up, this is no ordinary M.2 slot. Typically, M.2 is wired up for either the SATA, or NVMe protocols. That’s not the case here though.

The slot is designed for a Wifi/Bluetooth card, which communicate using a protocol known as SDIO. As the name suggests, this protocol is also used to communicate with SD cards. You might be able to see where this is going.

Using the adaptor board shared with ParkyTowers, it’s possible to connect a micro SD card to the M.2 slot. If you choose to have one of these boards made, be sure to note the requirement for a 0.8mm thick board, and the specific micro SD socket that is used.

As an aside, the ParkyTowers site is a great resource for all things related to thin clients – be sure to check it out if you haven’t already.

Incidentally, SDIO is the protocol used by the Raspberry Pi, for both the integrated Wifi/BT, and either the SD card or integrated storage on the compute modules.

Trying It Out

While it’s easy to add external storage to the 3040 using USB ports, maintaining the compact footprint and eliminating external devices can be an attractive proposition. We naturally had to built one to test it out.

Completed board
Micro SD card to M.2 adaptor for the Wyse 3040

Inserting the board into the 3040 is easy – simply unclip the bottom, and the slot is accessible. Be sure to check out our video if you’re struggling to get the 3040 open.

Make sure the pins in the socket line up with the contacts on the board. Depending on the manufacturing tolerances of the board, it’s possible it will need a little sanding to fit into the M.2 slot correctly. This was the case with one of the boards we tested.

There’s no mounting screw included, so you’ll need to source a suitable screw to hold the board down. These are available to purchase cheaply if you need one, but it’s fine to test without a screw if necessary, at least until you’re happy the board is working.

The micro SD card can be inserted at any time – it remains accessible even with the board screwed into place.

Once complete, the micro SD card should be seen by your OS of choice. If not…well, you’re not alone.

Technical Issues

Unfortunately, we encountered multiple issues with this board, which limit its usefulness.

The first issue relates to compatibility with micro SD cards. In our experience, only a couple of our cards were detected by the 3040, with the rest showing no signs of life at all. Tested in another PC, all of the cards are working correctly.

Micro USB cards we attempted to use
Collection of micro USB cards we attempted to use. Only the bottom two were detected by the 3040.

From the six micro SD cards above, only the bottom two were detected. Out of the six, these two appear to be lower capacity, more ‘budget’ cards compared to the other three. Whether this has anything to do with it is unclear, but it’s certainly possible.

A second issue tends to crop up from time to time when rebooting the 3040. While some boots are fine, the micro SD will occasionally disappear completely, only returning when reseating either the micro SD card or board. This can take a few attempts before it’s happy again.

It’s an inconvenience, and not entirely clear what would cause this behaviour. It’s fine if you rarely reboot, though, and doesn’t happen every time.

So It Doesn’t Work?

Well, yes, actually, it does work. We’ve held off on making this post for over a year now, and one of our 3040’s has had one of these boards installed the whole time. Not only is the card installed, but a few core OS folders have been moved onto it, making it critical for the system to function.

Not only this, but we also added a swapfile onto the card to boost the available system memory. Coupled with the fact the 3040 is running Gentoo, which compiles packages from source (and regularly needs the swapfile), it’s fair to say the micro SD has been given a good workout.

Other than the occasional hiccup when rebooting, it hasn’t skipped a beat. At the time of writing, it has been on for over two months.


So, do we recommend giving this a go? The answer to that is…probably not. At least, not unless you’re willing to work around the issues highlighted here.

There’s no guarantee your card will work at all, and if it does (and it behaves like ours), it could require reseating from time to time when the power is cycled.

It’s much easier to purchase a compact USB drive, and use this to expand the storage instead. The rear USB ports mean this can be done discreetly, and you’ll have cables extending from the rear anyway.

There’s also the front USB 3.0 port if speed is a concern.

That said, the boards are cheap to have manufactured, and the year of service ours has given us (so far) shows it’s more than possible to get it working. So, if you’re feeling adventurous, by all means give it a go.

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