A current AAA game takes 100 to 150 GB, so a 512 GB model is three or four big games. It’s the number one complaint from people who bought without thinking about it, and it arrives sooner than anyone expects.

There are two ways to fix it and they aren’t equivalent. This article covers which one applies to you based on what you play, and how not to waste money on the way.

First: which of the two do you need?

The short answer, so you don’t read more than you need to:

• If you mostly play indies, emulation and back-catalogue games → a microSD is plenty and costs a fraction.
• If you play recent AAA titles → a microSD will give you trouble, and what you want is a new internal SSD.

The reason is speed. Modern games stream textures continuously during play, not just at load time. A card considerably slower than the SSD can lengthen loads and cause occasional stutters in busy areas. On an indie or a five-year-old game that doesn’t happen, because they don’t demand that data flow.

The microSD: which to buy and which is wasted money

There’s a detail here that costs people money, and it’s the most important point in the article.

Don’t pay for a UHS-II card. Several handhelds — the Steam Deck among them — have a UHS-I reader, and a UHS-II card in a UHS-I reader runs at UHS-I speed. You’d be paying double for speed the device can’t use. Check which reader yours has before buying.

What does matter:

• The A2 rating. It’s designed for random access to small files, which is exactly what a game does, rather than copying one large video. That’s the label to look for.
• The brand. This is one of those categories where generic marketplace cards fail, corrupt data or lie about their capacity. The saving here is false.
• Capacity. As a guide, if you’re moving your lighter library across, 512 GB or 1 TB gives plenty of headroom for little money.

How to use it well: keep the internal SSD for the AAA games you’re playing now and send indies, emulation and anything installed “just in case” to the card. In Steam you can move an already-installed game between drives without re-downloading, from the game’s properties.

Replacing the internal SSD: the format you must confirm

This is the proper fix, and the one to approach carefully.

The format isn’t the desktop one. Most of these devices take an M.2 2230 — the short one — not the M.2 2280 from a tower, which is what comes up by default if you search “NVMe SSD” and what the SSD guide covers. But they don’t all use the same one: some models take an M.2 2242, an in-between length.

Confirm it in your specific model’s manual before buying anything. Buying the wrong format is the most expensive and most common mistake in this process, and no adapter saves you.

What the swap involves:

1. Opening the device. It’s more delicate than a tower and on some models it affects the warranty. Find the teardown guide for your model before you start.
2. Reinstalling the OS. The new SSD arrives empty. On SteamOS you use Valve’s official recovery image and a USB stick; on Windows models, Microsoft’s installer plus the manufacturer’s drivers.
3. Re-downloading your games. Unless you clone the old drive, which needs a USB enclosure for the old SSD.

One tip that saves grief: if you’re replacing the SSD, back up your save files first. Steam’s cloud sync covers most of them, but not every game has it enabled.

How much storage to buy up front

If you’re still choosing a device, this saves you the whole problem.

Your library	What to buy
Indies, emulation, back catalogue	512 GB + a fast microSD
Recent AAA, two or three at a time	1 TB internal from day one
AAA and you don’t want to think about it	2 TB internal

Paying for more storage at purchase almost always works out better than changing it later, because you skip the teardown, the reinstall and the download hours. The microSD is the complement, not the main plan.

Frequently asked questions

How much space does a handheld game take? A current AAA title, 100 to 150 GB. On a 512 GB model that’s three or four big games once you count the OS.

Is a UHS-II microSD worth it? No, if your device has a UHS-I reader — as the Steam Deck does. The card will run at UHS-I speed anyway and you’ll have paid double for nothing.

Which microSD should I buy for a handheld? An A2-rated card from a known brand, since A2 is the rating built for the random access a game performs. Avoid generic marketplace cards: this is a category where they genuinely fail.

Can I put AAA games on the microSD? You can, but it’s where they run worst: they stream textures during play and the card is considerably slower than the SSD. Keep the card for indies, emulation and older titles.

Which SSD does my handheld take? Most use M.2 2230, the short one — not the desktop M.2 2280. Some models take M.2 2242. Confirm it in your model’s manual before buying.

Can I move an already-installed game to the card? Yes. In Steam you do it from the game’s properties, without re-downloading.

Bottom line

The rule, in one line: microSD if your library is light, a new SSD if you play recent AAA — and in that case, check first whether your model takes a 2230 or a 2242.

And if you’re still at the choosing-a-device stage, pay for the internal storage up front. It costs less than the time it takes to fix later. The models by tier are in best handheld gaming PC.