I swear I don’t actually have anything against the Nintendo Switch 2, other than its suspect attempt at Zoom Meetings But Games and some slight jealousy that it got DLSS support before a PC handheld did. Even so, I do feel obliged to warn Steam Deck owners – and, in fact, anyone who has any current portable PC – away from microSD Express cards, support for which is one of the Switch 2’s key storage upgrades.
microSD Express fancies itself the horseless carriage to microSD’s knacked mare, being able to talk to its host device over an SSD-like PCIe/NVMe interface (rather than microSD’s aging UHS tech) and thus achieve transfer speeds approaching 1,000MB/s. That’s three times quicker than the fastest ‘standard’ microSDs, which naturally looks like delicious bait for the discerning handheld wielder. If it’s good enough for the Switch 2, posits a growing number of reddit threads and forum posts, could it then cut load times on a Steam Deck or ROG Ally as well?
No, is the answer to that. Although microSD Express could well be the expandable storage of choice for future handhelds – the Xbox ROG Ally is skipping it, but who knows with the mysterious Steam Deck 2 – it won’t get anywhere near its top speeds when plugged into the portable PCs of today. That’s because the devices themselves also need Express compatibility, and none do, because they’re all still sticking with UHS-I and UHS-II interfaces. Which, in turn, means any microSD Express card that slides into a current-gen Deck will be limited to the performance ceilings of the older-style slot.
Despite the results being, broadly, a forgone conclusion, I was still curious as to what happens when you send one of these newer cards back in time to work on a non-Switch 2 handheld. I therefore got hold of a 256GB PNY microSD Express card, launched just recently for you-know-what, and delivered it to the UHS-I receptacle of an original LCD Steam Deck. From there, I pitted it against the outright fastest microSD card we’ve tested on RPS, a SanDisk Extreme Pro, in a series of game-launching races. The results may SHOCK you, unless you know the fundamentals of PC storage, in which case they’ll do no such thing.

Even if we discount the weird outlier that is Aperture Desk Job, the microSD Express card isn’t merely no faster the UHS-based Extreme Pro – it is, consistently, a second or two slower. And while I didn’t test all five games, I did see some evidence that the Extreme Pro is better at cutting in-game load times as well, with it firing up a Shadow of the Tomb Raider file in 15.6s to the PNY card’s 18s.
I’m satisfied that there isn’t anything mechanically wrong with the latter. I did wonder if it was suffering the commonly reported microSD Express weakness of overheating, which would theoretically cut performance via throttling, but then if the Steam Deck was blocking it from its higher speeds than it shouldn’t be running itself ragged to begin with. A laser thermometer check also confirmed it was peaking at the same 37°c in its slot as the Extreme Pro. Nay, we can chalk this up to a combination of the SanDisk card just being unusually excellent, and the PNY microSD Express being lost and confused inside a slot it doesn’t belong.
Point being, here we have confirmation that where current-gen handheld PCs are concerned, a microSD Express card will do nothing that an older, more interface-appropriate storage card will not. Except, perhaps, waste your money. The PNY model I tested is $56 for 256GB, nearly twice the price of an equivalent-sized SanDisk Extreme Pro and only half a buck less that card’s 512GB version. Meanwhile, the Samsung Pro Plus, my overall top pick not just of microSDs but of Steam Deck accessories in general, is just $28 for 256GB and $43 for 512GB.
I’d still potentially like to see microSD Express on a handheld PC of the future, hopefully once card prices have dropped. Storage standards change over time, and imagine how awful it’d be if solid state drives never became accessible enough to replace HDDs. For now, though, just let the Switch 2 be their guinea pig – or do most PCish thing of all, and upgrade the Deck’s internal SSD instead.