An SD card is an essential component in the Raspberry Pi and other SBCs. The slot is baked into the board and is fast enough to run a customized operating system. Many popular operating systems for Raspberry Pi, like DietPi and the official Raspberry Pi OS, comfortably work on an SD card. However, keeping just one micro SD card for your Raspberry Pi or other SBC isn't a good practice.

I prefer to keep multiple microSD cards for my Raspberry Pi, each serving a specific purpose. Some act as a backup for my main Pi OS, while others serve as a fresh setup, and others fulfill niche use cases such as self-hosting, retro gaming, or home automation. I use a bunch of micro SD cards, all with varying storage space and data, and it's made my SBC experience less cumbersome. Let's discuss these reasons in detail.

Swapping operating systems

Why stick to one?

If you are an SBC user like me, there's a high chance you swap operating systems depending on the use case. It's painstaking to wipe down your current card, which contains all the data and the installed apps. The wiping happens instantly with any OS flashing utility like Raspberry Pi Imager or Balena Etcher. But it takes a lot of time to reinstall and set up everything.

So, I keep the SD card intact and flash the test OS on another one. That way, you can test and try something new without obliterating your progress. If you don't like the new OS or don't need it, just power off the Pi and reinsert your primary micro SD card, and you are good to go. I keep an instance of DietPi handy, a card for RetroPie, and one for standard 64-bit Raspberry Pi OS.

Backups are important

A dedicated backup card

Swapping operating systems on an SBC is a good practice; therefore, creating a backup is unnecessary when you have a dedicated OS card. Well, microSD cards can become corrupt and fail, too. When that happens, you'll regret that you don't have a backup, and that's where the backup card becomes necessary. Heavy data logging or prolonged usage can demolish your SD card and leave your system out of service.

However, you can use a backup tool like the SD card copier in Raspberry Pi OS to create a complete backup with partitions. You can use an alternative card as a backup and a card reader to copy the files and create a bootable backup. Several other backup tools are available if you use a different SBC OS. So, an additional backup SD card for your Pi can ensure redundancy and swiftly get the system up and running again.

Doesn't drain the pocket

Cheapest storage of them all

The newer generation Raspberry Pi 5 supports NVMe SSDs out of the box. It’s a great way to enjoy desktop-like speed on your Pi, but the setup costs a lot. SD cards are dirt-cheap compared to the cost of the Pi and are widely supported. You can buy a 32GB SD card for as low as $5 and create a system backup, install another operating system, or create replicas of a single OS.

You don't need to invest $40-50 for an SSD or a good-quality USB drive. Not all SBCs have USB 3.0 ports, so the SD cards remain the fastest choice. For example, the Raspberry Pi Zero 2W has a USB 2.0 port and an SD card slot, but the latter is faster. You can get a high-endurance SD card for the same price that can handle continuous write operations.

No extra setup elements

A clean Pi setup

The SD card slot is available on the board itself. You don't need to worry about which port to use or purchase another connection device. A Raspberry Pi 5 supports an NVMe SSD, but to do that, you need to buy a HAT module that connects to the PCIe slot on the board. USB ports also fill up very fast when adding accessories like a keyboard, mouse, storage drives, or anything else.

You may have to use a USB hub to extend the connection, making the setup clumsy. There's also a problem of loose or flimsy connections with USB hubs. The SD card slot is fixed and grips the card well, so you don't need to worry about an interrupted connection when using the SD card as a boot drive.

SD cards and SBC are inseparable

For SBC tinkerers like me, SD cards will always remain a superior choice. It is widely available and has no known support issues. You can replace them without hurting your pocket, and keeping multiple cards for backups and a new OS makes the DIY stuff easy. Swapping operating systems based on your needs becomes a simple task with dedicated SD cards.

This way, you can spend more time focusing on the project rather than worrying about a fresh OS installation and system configuration. Make it a habit to get at least two cards for your SBC.