It looks like Valve has quietly downgraded the internal storage on some Steam Deck models. We recently wrote about how the company has told Steam Deck owners not to upgrade their SSDs to larger (longer) models, but Valve has been making tweaks itself. 

Valve has potentially quietly downgraded the SSDs on both the 256GB and 512GB Steam Deck models. Moving from PCI express 3.0 x4 SSDs to x2 SSD instead. This means the drives use half the number of PCIe lanes and therefore have potentially 50 per cent less bandwidth. 

This is noted on the Steam Deck's official specs page where the drive specs are listed as:

  • 256 GB NVMe SSD (PCIe Gen 3 x4 or PCIe Gen 3 x2*)
  • 512 GB high-speed NVMe SSD (PCIe Gen 3 x4 or PCIe Gen 3 x2*)

The asterisk leads to a note which suggests Valve thinks there won't be a noticeable problem for gamers:

"Some 256GB and 512GB models ship with a PCIe Gen 3 x2 SSD. In our testing, we did not see any impact to gaming performance between x2 and x4."

As PC Gamer reports, a check on the Wayback Machine shows that that same page showed that both these models ran with an x4 NVMe set up earlier this year. Valve has made it clear that testing has shown that there's no problem with gaming performance as a result. But if you've pre-ordered a Steam Deck and were expecting a PCIe Gen 3 x4 NVMe then you might be disappointed. 

We'd recommend grabbing a good microSD card to go with your Steam Deck anyway, as you'll soon fill up the internal storage.