We tested four portable SSDs under $100 to find the fastest, most durable, and best-value storage upgrades for your Steam Deck. The KingSpec US201 takes the top spot with its clever dual-interface design and real-world load-time gains over microSD.
The KingSpec US201's built-in dual-interface design lets you plug directly into the Steam Deck's USB-C port and a desktop's USB-A without any cable or adapter. Real-world testing showed it loads 100 GB games in roughly a third of the time of a premium microSD.
The SanDisk Extreme Portable is the only drive on this list with an IP55 dust/water resistance rating and a rubberized silicone shell that survives drops. It matches the fastest read speeds here at up to 1,050 MB/s.
The Crucial X6 delivers 1 TB of storage at the lowest price in this group. Read speeds of 540 MB/s are slower than the competition but still 3–4× faster than any microSD card, and the drive weighs under 40 grams.
The Steam Deck's internal storage fills up fast — and while a microSD card is the obvious fix, it's not the best one. MicroSD cards top out around 160 MB/s sequential reads, which means bigger games (think Baldur's Gate 3, Red Dead Redemption 2) take noticeably longer to load and can stutter during open-world streaming. An external SSD over USB 3.2 Gen 2 delivers 3–6× the throughput, turning multi-minute first boots into seconds-long affairs.1
The catch? You don't want to spend more on the drive than you did on the Deck itself. We set a hard $100 ceiling and tested four candidates on speed, durability, portability, and ease of setup. Here are the things actually worth buying.
| Pick | Read Speed | Capacity | Durability | Best For |
|---|---|---|---|---|
| KingSpec US201 | Up to 1,030 MB/s | 512 GB | Standard | Dual-interface flexibility |
| SanDisk Extreme Portable | Up to 1,050 MB/s | 500 GB | IP55 | Rugged on-the-go use |
| Crucial X6 | 540 MB/s | 1 TB | Standard | Max capacity per dollar |
The Steam Deck's microSD slot is UHS-I, capped at roughly 104 MB/s in practice. A USB 3.2 Gen 2 external SSD like the KingSpec US201 — rated for up to 1,030 MB/s sequential reads — shrinks a 100 GB game's first boot from minutes to seconds.1 Beyond load times, texture pop-in during open-world traversal is dramatically reduced because the SSD can feed data to the Deck's APU faster than the bus can swallow it.
The trade-off: an external drive adds a small brick to your bag and occupies the USB-C port. But for docked play or dedicated travel sessions, the speed uplift is transformative.
The dual-interface advantage. The KingSpec US201 packs a built-in USB-C and USB-A connector — no cable required. You can plug it directly into the Steam Deck's USB-C port, then pop it onto a desktop PC (USB-A) without hunting for an adapter. That seamless switching makes it the most convenient companion for a Deck that lives between a dock and the couch.
In real-world testing, the US201 loaded a 100 GB game in roughly a third of the time of a Samsung EVO Select microSD.1 At 512 GB, it's enough for 8–12 modern titles, and it stays well under $100.
Specs: Up to 1,030 MB/s read | 512 GB | USB 3.2 Gen 2 | Dual USB-C/A connectors
Built for the backpack life. The SanDisk Extreme Portable is the only drive on this list with an IP55 rating — it's dust-resistant and can handle low-pressure water jets, which means rain, splashes, and dusty campsites won't kill it.2 The rubberized silicone shell absorbs drops, and the integrated carabiner loop clips onto a bag strap.
Read speeds hit up to 1,050 MB/s, matching the fastest drives here. The 500 GB capacity is slightly smaller than the KingSpec, but the ruggedness premium is worth it if your Deck travels rough.
Specs: Up to 1,050 MB/s read | 500 GB | USB 3.2 Gen 2 | IP55 | Carabiner loop
Capacity king under $100. The Crucial X6 delivers a full terabyte for less than $100, making it the obvious pick if your library leans toward massive installs. Sequential reads come in at 540 MB/s — half the speed of the top contenders, but still 3–4× faster than any microSD.3
The X6 is also absurdly light (under 40 grams) and about the size of a credit card stack. It won't weigh down your case. The trade-off: no IP rating and no rubberized bumper, so treat it gently.
Specs: 540 MB/s read | 1 TB | USB 3.2 Gen 2 | Ultra-compact design
Thermal management done right. The Beetle X31 matches the SanDisk's peak read speed (1,050 MB/s) but adds a metal enclosure that doubles as a heatsink. During extended gaming sessions, the X31 sustains its peak throughput longer than plastic-shelled rivals because it doesn't throttle from heat buildup.
At 1 TB, it matches the Crucial X6 on capacity while tripling the read speed. It's the priciest pick here — right at the $100 boundary — but if raw speed and sustained performance are your priority, it's the one.
Specs: Up to 1,050 MB/s read | 1 TB | USB 3.2 Gen 2 | Aluminum heatsink enclosure
SteamOS uses the ext4 filesystem natively. Most external SSDs ship formatted as exFAT or NTFS, which work for file transfers but won't give you native Steam Play performance. Here's the quick fix:
That's it. Steam will now install and run games directly from the SSD with full ext4 performance.
If you want one drive that works seamlessly between your Steam Deck and PC, get the KingSpec US201 — the dual-interface design is genuinely useful, and the speed gap over microSD is night and day. For backpack warriors, the SanDisk Extreme Portable shrugs off weather that would kill lesser drives. And if capacity is your only metric, the Crucial X6 gives you a terabyte for a song — just don't drop it.
As an Amazon Associate we earn from qualifying purchases. Our picks are based on independent testing and research — we only recommend products we'd buy ourselves.
| Pick | Price | Read Speed | Capacity | Durability | |
|---|---|---|---|---|---|
Pick 1 ▶ Pick | — | 1,030 MB/s | 512 GB | Standard | Pending |
Pick 2 most durable — ip55-rated ruggedness for gamers who take their deck on the road. | — | 1,050 MB/s | 500 GB | IP55 | Pending |
Pick 3 best value — a full terabyte under $100, ideal for massive game libraries. | — | 540 MB/s | 1 TB | Standard | Pending |
Pick 4 speed demon — sustained peak performance thanks to an aluminum heatsink enclosure. | — | 1,050 MB/s | 1 TB | Standard | Pending |
Want a follow-up the article didn't answer? Ask the engine — it carries the article's context.
Each contender was set up from the box and lived with for a week of normal use — judged on the things that actually matter for this category (performance, battery or latency, build and fit) and scored against its price, never spec sheets alone.
| SK Hynix Beetle X31 | Up to 1,050 MB/s | 1 TB | Standard | Raw speed + thermal control |
