As we reported yesterday, while Valve has been increasing Steam Deck production, they’ve also quietly downgraded a key component going into the machine. Some (but not all) 256 GB and 512 GB Steam Deck models will now ship with a PCI express 3.0 x2 SSD instead of a PCI express 3.0 x4 SSD. As you would expect, an x2 SSD offers around half the writing and reading speed of an x4 SSD. The Deck website says this change will have no effect on “gaming performance,” but people were understandably skeptical. Surely, this change would come at some sort of cost?
The answer is, yes, the SSD change will indeed come at a cost, but according to comments Valve provided to PC Gamer, it won’t be a big one. Basically, file transfer speeds will be slower in rare cases, but due to various hardware bottlenecks, the Deck wasn’t really using the full bandwidth of the 4x SSD most of the time and thus gameplay should be largely unaffected.
SSD performance is currently gated by factors not related to PCIe bandwidth. In extremely uncommon cases, differences in read/write speed caps may minimally impact file transfer speeds, but OS performance, loading times, game performance, and game responsiveness are identical between the x2 and x4 drives.
As for why the change was quietly made, Valve chalks it up to a supplier issue. The unspoken, is that Valve likely expanded their supplier pool in order to produce Steam Decks more quickly.
Many Steam Deck components come from multiple suppliers for improved redundancy and production capacity. One of our SSD suppliers provides PCIe Gen 3 x4 NVMe SSDs, while another provides a x2 (2 lane) SSD. Our team has tested both components extensively, and determined that there is no impact to performance between the two models.
Steam Deck Q3 reservation emails start going out today, so check that inbox if you pre-ordered. What do you think? Is Valve’s explanation adequate? Or does the SSD downgrade affect your desire for a Deck?