The Nintendo Switch 2 sure has been good for microSD Express. The standard has been around since 2019, but Nintendo making it required for its new handheld has made it go from nonexistent to robust and affordable virtually overnight. Samsung, which already makes one of the best Nintendo Switch 2 microSD Express cards, has tossed another card on the pile with the Samsung P9 microSD Express card – and it’s the fastest I’ve tested yet.
Samsung lent me the 256GB version of this card, which, at $54.99, is priced right between the PNY and Onn cards I’ve already reviewed – and is even $5 cheaper than the one it makes for Nintendo. It’s also measurably faster than both of those cards, beating both by a mile in write speeds and outdoing the Onn card in read speeds. And from where I’m sitting, it’s a better value than either of those options – and probably any similar cards from Lexar or SanDisk.
Throughput
Nintendo’s move to microSD Express gives its console internal SSD-like storage speed without all the hassle of opening your console to install an M.2 SSD like the PS5, or requiring gamers to buy an overpriced, bespoke card to plug into a special port like the Xbox Series X/S. How fast is Samsung’s microSD Express card, exactly? Well, really dang fast if we’re to believe the 800MB/s sequential read throughput that Samsung promotes on its site. But that’s misleading in this context; because of the way game files are structured, it’s closer to the around 90MB/s I saw in testing.
But don’t fret over that lower number. Something like a video file has its data neatly lined up, and when read, it’s read sequentially. But a video game is really a package full of smaller files, data that’s stored non-contiguously – that’s what the “random” read and write spec is referring to. And in this situation, the transfer process never has the runway it needs to get up to sequential throughput levels. The small-file makeup of video games is why, as you’ll see in my testing below, file transfer throughput can vary quite a bit from one game to the next. Some games have a smaller number of files but in larger blocks, while others might have thousands of tiny files that bog down the process.
The more important metric for random reads and writes is the number of input/output operations per second, or IOPS, a card can do – and the P9 can, by Samsung’s reckoning, reach up to 65,000 IOPS in random reads and 52,000 IOPS in random writes. That’s very fast compared to the theoretical (but rarely actualized) 4,000 IOPS capability of some standard microSD cards. Unfortunately, I don’t have a standalone microSD Express card reader, so I can’t actually confirm their IOPS numbers with PC testing software like CrystalDiskMark. Instead, I have to rely on like-for-like game transfers to get a sense of which card is better at what.
Performance: Load Times
Loading times for games is where most players’ microSD Express card choice actually affects them. To test this, I simply started up the same games several times and averaged how long it took to get from first opening a game to its start screen. Across nearly every game I tested, the 256GB Samsung P9 and the same-size PNY card I also reviewed did about the same. Donkey Kong Bananza loaded in just 21 seconds on average for either, while it took just over 9 seconds to get into The Legend of Zelda: Tears of the Kingdom.
The one exception was Mario Kart World, which took about two seconds longer with Samsung’s card than PNY’s. Even the (Walmart house brand) Onn card loaded Mario Kart World about a half-second faster than the P9. Notably, each time you boot up MKW, the start screen loads a different region of the game’s open world, letting you seamlessly jump into driving around it by pressing the “+” button on your controller. It’s possible that the P9’s slower performance was just luck of the draw.
Otherwise, both cards outperformed the Onn, sometimes by just a fraction of a second, others by multiple seconds – it took about three seconds longer to load Fast Fusion from the Onn card than the others; and about five seconds longer for Donkey Kong Bananza. Going by game load times, Samsung’s card and PNY’s are neck and neck, and both tend to be a little slower than the Switch 2’s internal storage.
Performance: Throughput
I tested read and write throughput by timing game file transfers to and from the card, and the story was much the same here as with loading: Samsung and PNY were a cut above Onn. I started by moving games from the card to the console to check read throughput. Here, the Samsung P9 averaged just under 80MB/s for Mario Kart World(21.9GB), 87.25MB/s for Donkey Kong Bananza (8.9GB), and 96MB/s for Resident Evil 4 (12GB). Compare that to the PNY card’s transfer throughput of 81.7MB/s, 88.7MB/s, and 76.9MB/s, respectively. So about the same, apart from the P9’s outlier Resident Evil 4 result.
Write speeds are where the Samsung P9 shined. It consistently hung out between 71MB/s and 73MB/s across every transfer test, unlike both the PNY and Onn cards, which were slower, and varied heavily between tests. Each put up between 52 and 62MB/s in random write throughput. That meant it took me just four minutes to write my 17.2GB Super Smash Bros Ultimate copy to the Samsung P9. That took almost five minutes for the Onn card and close to six minutes on the PNY card. Writing Mario Kart to the Samsung P9 was about 2.5 minutes faster than to the other cards, although it’s worth noting here that a recent update shrank the game by almost 3GB after that test. Still, that was a 72MB/s transfer, compared to 54–56MB/s to the other cards.
The Best of the Budget Cards
Samsung P9 is measurably better than its Onn and PNY peers, and at $55, it’s a no-brainer, at least compared to the $61.99 PNY card. Whether it’s worth it compared to the $46.77 Onn card depends on how well you can afford the difference and how often you shuffle files between your internal storage and your microSD Express card. If that doesn’t happen often, this Samsung card might be worth it just to save your money or put it towards another game – that nine bucks you save will get you most of the way toward Fast Fusion, a lovely antigrav racer for the F-Zero-starved among us.
Wes is a freelance writer (Freelance Wes, they call him) who has covered technology, gaming, and entertainment steadily since 2020 at Gizmodo, Tom's Hardware, Hardcore Gamer, and most recently, The Verge. Inside of him there are two wolves: one that thinks it wouldn't be so bad to start collecting game consoles again, and the other who also thinks this, but more strongly.
