Valve has updated its official specifications page for the Steam Deck to confirm that the 256 GB and 512 GB versions of the handheld may ship with different SSDs than what the company had originally advertised. Instead of a PCIe Gen 3 x4 SSD, prospective Steam Deck owners who go for the 256 GB and 512 GB models might end up with a x2 storage solution that only leverages two lanes of the PCIe interface. This would indicate a halving in potential bandwidth, but Valve has clarified that it’s conducted tests and found no impact to gaming performance between the x2 and x4 SSDs. Steam Deck owners can figure out which SSD they have by going into the Hard Disk Drive option buried within the Device Viewer, which should show a code that can be used to identify the hardware. Valve has priced its 256 GB and 512 GB Steam Decks at $529, and $649, respectively. The base model costs $399 but only comes with 64 GB of eMMC storage.
If you want to find out which version you have, hold down your Steam Deck’s power button and select Desktop Mode. Then search Device Viewer in the Applications Menu search bar. Under Devices, go to Storage Drives, and tap the Hard Disk Drive.
In the right panel it’ll have a code. Our 512GB review model has a Phison ESMP512GKB4C3-E13TS drive. That seems to be a custom 2230 SSD using Phison’s Gen3 x4 E13 controller. So, you want to check whether your code ends with -E13T, too, or something else entirely. If it includes a code like -E08 (Phison’s Gen3 x2 controller) then your Deck is one of those with a drive running on a Gen3 x2 interface.
Source: Steam Deck (via PC Gamer)