The Asus ROG Ally offers superior performance when compared to the Steam Deck and several other handhelds. The more powerful ROG Ally X released in 2024 widens the gap with better performance, an improved screen, and enhanced ergonomics. Not just that, the entire ROG Ally family sports a UHS-II microSD card slot, allowing for cards that are faster at both reading and writing than UHS-I, the baseline spec found in the Steam Deck, the Nintendo Switch, and several other devices. In other words, you’ll likely see much faster download speeds if you have the right card.

According to Lexar, UHS-II triples the maximum transfer speed of UHS-I, topping out at 312 MB/s instead of 104 MB/s. However, despite the proliferation of microSD cards, there are very few UHS-II microSD cards out there. Currently, household names in storage, like Samsung and SanDisk, do not make UHS-II microSD cards. The few UHS-II options that exist are much more expensive than what you might be used to paying for a microSD card. What’s a little more concerning is that the current options don’t run at the full speed allowed by the UHS-II interface.

If you’re comfortable opening your ROG Ally (it won’t void the warranty), we suggest considering buying an M.2 SSD instead and installing it, as it’s a better value in terms of storage, and doing so will yield faster-performing storage than microSD. However, if you’d prefer to go the easier route and are okay with paying a premium for perhaps a little extra speed, we’ve found a couple of readily available models below.