Though r/SteamDeck is littered with pictures of people showing off their Deck or asking for a support request, there are occasionally some useful posts there. One such instance is what you should be getting when buying a MicroSD card. And I feel it’s important enough to mention it here, since I talk about the Steam Deck pretty frequently and some don’t know what they should get.

You should be getting a U3 A2 UHS-I. Here’s a breakdown of all that jargon:

  • “U” describes the minimum read/write speed. 1 is 10 MB/s, 3 is 30 MB/s. Large games will take “hours upon hours” to download if you use U1 because of write operation dropouts
  • “A” refers to the random read/write speed. “A2” is the second generation and is preferred over A1 due to “greater efficiency in scenarios such as texture streaming in open-world games”
  • “UHS-I” is the bus type of the card. There’s only one other type: UHS-II, but this is pointless in getting since the Deck does not support the faster bus speed of UHS-II. Save yourself some money by not getting UHS-II

Newer MicroSD cards may have a “V” followed by a number, such as “V30.” This is something that you don’t really need to worry about, as it only describes the speed with which the card can record video.

The poster then describes what kind of brands you should be looking for: SanDisk, Lexar, Integral, or Samsung. Apparently some Samsung cards may not be as reliable when it comes to sequential speeds, however.

Finally, test the speed of your card once you get it with KDiskMark. Available as an AppImage.

Special thanks to u/Sjknight413 for the post.